A 96-year-old who wrote a song for his late wife has made the US iTunes top 10, alongside Katy Perry and Lady Gaga.

Fred Stobaugh, whose wife Lorraine died in April, has no previous musical experience and wrote the song on a whim for a competition.
He submitted his handwritten lyrics by post and, although the contest was online-only, the organisers were so moved they put the words to music.
Oh Sweet Lorraine is number seven on US iTunes and has 1.9m YouTube views.
Billboard magazine said the song had sold 6,000 copies so far, placing it at number 49 in its rock digital songs sales chart.
The track is also in the iTunes charts for Austria, Switzerland, Germany, Sweden, Norway and Luxembourg.
"Oh sweet Lorraine," the chorus begins, "I wish we could do all the good times over again."
Stobaugh does not perform the song himself - on his original submission, he wrote: "I don't sing, I would scare people, haha!"
Vocals are provided instead by Jacob Colgan, whose Green Shoe Studio organised the original contest.
A documentary about the recording of the song, uploaded to YouTube in July, explains how the recording came about.
"What made Fred's entry so special to us was, one, it's an online contest. People are supposed to upload their videos," Colgan says in the clip.
"But, instead of a video, we received a very large manila envelope. Well, I was excited to see what it was. Lo and behold, it was a letter from a 96-year-old man who said, 'I've written a song for my wife'.
"He sounds like a sweet guy," he continues, "but, as I'm reading through the letter, I begin to realise that his wife had just passed away a month earlier."
Stobaugh says the song, his first, came to him out of the blue.
"After she passed away, I was just sitting in the front room one evening by myselfâ€¦it just [came] to me. I kept humming it."
The finished recording is a simple, country-tinged lullaby. The documentary shows Stobaugh overcome with emotion as he hears it for the first time, covering his face with his hand as he tells Colgan: "It's wonderful, it's wonderful".
"She was just the prettiest girl I ever saw," he says of meeting Lorraine in 1938. "Real timid-like. I just fell in love with her right there."
"I really, really miss her."


A petition calling for last month's mayoral election in Tower Hamlets to be held again has been submitted to the High Court.

The Red Flag Anti-Corruption Party has accused Lutfur Rahman's party of electoral fraud, corruption and political smears.
His opponents claim voters were intimidated at polling stations and that some were told how to vote.
The mayor has consistently denied any wrongdoing.
Speaking to BBC London 94.9 on Tuesday, the mayor, who was re-elected on 22 May, said: "I have done, and we have done, nothing wrong."
The petition has been brought by four people who are now applying for a hearing at the High Court.
It claims:
Allegations have also been made against returning officer John Williams.
He is alleged to have allowed people to canvas for votes inside polling stations, to accompany voters into the compartment when they cast their vote and to leave campaign material in and around voting compartments.
Andy Elram, Red Flag party member who stood against Mr Rahman in the election, said: "If the court decides there should be a recount and the numbers don't add up, they're not consistent, then the court has the power to order another election."
Mr Williams has said he will not comment specifically on the petition as he is taking legal advice.
However, he says the measures he put in place for the elections were the toughest available within the current law.
He added that he worked closely with the Metropolitan Police and the Electoral Commission to combat fraud and to investigate fully any allegations that had surfaced.
This petition is the latest in a series of investigations into Tower Hamlets.
The Metropolitan Police is investigating 84 complaints into the election.  It said in the majority of cases, no criminal offences had been committed.
Separately, the government is looking into claims made by BBC One's Panorama programme that the mayor had disproportionately funded Bengali groups in order to get their vote in his first term in office.
The Electoral Commission has also launched a review into the count.


An Australian politician has lodged a complaint with the country's Human Rights Commission after a newspaper article labelled him an "angry white male".

Section 18C of Australia's Racial Discrimination Act makes it illegal to insult someone because of their race.
Senator David Leyonhjelm, a libertarian, says Section 18C damages free speech and should be repealed.
But he has lodged a complaint under the law in an attempt to prove a point.
Newspaper columnist Mark Kenny made the "angry white male" comments in an article that also labelled Mr Leyonhjelm a "boorish, supercilious know-all with the empathy of a besser block".
Mr Leyonhjelm said that while he was not offended by the comments, he saw an opportunity to demonstrate why Section 18C should, in his opinion, be repealed.
"Under the Act, Mr Kenny's article is unlawful because his article was reasonably likely, in all the circumstances, to offend, insult, humiliate or intimidate another person or a group of people on the basis of their colour," he said in a statement.
He said the comments were "reasonably likely â€¦ to offend or insult some white males".
"Assuming the adjudicators at the Human Rights Commission are guided by the law and not racists, I anticipate the complaint should succeed. Of course, if I succeed in having Section 18C repealed, Mr Kenny will be free to insult me as much as he likes," the statement said.
Section 18C says that a person cannot publicly "offend, insult, humiliate or intimidate" another person or group because of their "race, colour or national or ethnic origin".
Conservatives have campaigned against the law since it was used to prosecute prominent right-wing commentator Andrew Bolt.
Former Prime Minister Tony Abbott said he would repeal Section 18C in 2013, but later abandoned his attempt amid strong opposition.
Mr Abbott reignited debate this week when he said he should have pursued a less ambitious reform that removed the words "offend" and "insult" from the law.


A court in Saudi Arabia has sentenced the Shia cleric Sheikh Nimr Baqir al-Nimr to death, his family says.

Sheikh Nimr Baqir al-Nimr's brother said he was found guilty of seeking "foreign meddling" in the kingdom, "disobeying" its rulers and taking up arms against the security forces.
The cleric was a vocal supporter of the mass anti-government protests that erupted in Eastern Province in 2011.
His arrest two years ago, during which he was shot, triggered days of unrest.
Oil-rich Eastern Province is home to a Shia majority that has long complained of marginalisation at the hands of the Sunni royal family.
Protests began there in February 2011 after the start of the pro-democracy uprising in neighbouring Bahrain, which has a Shia majority and a Sunni royal family.
The Saudi authorities deny discriminating against Shia and blame Iran for stirring up discontent.
Sheikh Nimr's brother Mohammed said on Twitter that he had been sentenced to death by Riyadh's Specialised Criminal Court, which tries terrorism cases, on Wednesday morning.
A statement by the cleric's family described the verdict as "discretionary", saying the judge had the option of imposing a lighter sentence, according to the Associated Press. It also warned that the trial had been "political" and had set a "dangerous precedent for decades to come".
When Sheikh Nimr, who holds the rank of ayatollah, went on trial in March 2013 prosecutors called for his execution by "crucifixion", a punishment which in Saudi Arabia involves beheading followed by public display of the decapitated body.
Human rights groups expressed concern at the time that he would not receive a fair trial. They also said he had still not been given access to adequate medical care for the gunshot wounds he received during his arrest in July 2012, something denied by the authorities.
Police shot Sheikh Nimr in the leg four times in disputed circumstances as they detained him after a car chase in Eastern Province's Qatif district.
Officials said he rammed a security forces vehicle, leading to a gun battle. However, his family disputed the allegation that he resisted arrest and insisted that he did not own a weapon.
The cleric was held for eight months before being charged and reportedly spent the first four in an isolation cell at a prison hospital in Riyadh.
Activists and relatives say Sheikh Nimr, who has a wide following among Shia in Eastern Province and other states, supported only peaceful protests and eschewed all violent opposition to the government.
In 2011, he told the BBC that he supported "the roar of the word against authorities rather than weapons... the weapon of the word is stronger than bullets, because authorities will profit from a battle of weapons".
His arrest prompted days of protests in which three people were killed.
Human Rights Watch said more than 1,040 people had been arrested at Shia protests between February 2011 and August 2014. At least 240 are still believed to be in detention.
"I think the message that Saudis are saying is: 'We will arrest anybody. We don't care how high profile they are... nobody is above this. We don't have any tolerance. We don't have any flexibility,'" HRW Middle East researcher Adam Coogle told AP after Sheikh Nimr's sentencing.


Chinese President Xi Jinping has promised to strengthen protections on intellectual property and clear obstacles to investment in China, at a meeting with US technology leaders.

Speaking in Seattle he said: "Without reform, there will be no driving force; without opening up, there will be no progress."
Amazon founder Jeff Bezos and Apple CEO Tim Cook were among those attending.
US companies are eager to tap into China's massive market of consumers.
Mr Xi addressed recent China's recent economic troubles, and said the government was taking steps to address it.
However he said, "I believe in the long run that the fundamentals of the Chinese economy are good."
Oh to have been a fly on the wall when President Xi sat down with Apple's Tim Cook, Amazon's Jeff Bezos, Satya Nadella of Microsoft and other US technology leaders. We are told the conversation covered regulation and clean energy - but surely there must have been something juicier?
The truth is that China and the tech giants both need and fear each other. The technology firms know it is where their future profits should come from - Apple now makes about a quarter of its revenue from China, while Amazon despite years of investment is still struggling to make an impact. For China, demand for American technology products is what keeps millions in manufacturing jobs.
But while both China and the US appear committed to expanding their technology relationship, their very different views on internet freedom mean progress will be difficult.
But at a time when demand for technology products is fragile, China still looks like a huge opportunity for growth. That is why the tech tycoons will have tried their best to charm their visitor.
Mr Xi stressed that reaching agreements to ensure continued robust international trade was a top priority.
US officials have said the two counties have made progress in negotiating a new trade agreement, but key issues remain unresolved.
Former US Treasury Secretary Henry Paulson moderated a closed-door discussion with more than 30 business leaders before Mr Xi's public remarks.
Representatives from Twitter and Google were notably missing from the event. China blocks those companies' websites.
However, Mark Zuckerberg the chief executive of Facebook, which is also blocked in China, met with Mr Xi during the forum.
Mr Xi travels to Washington DC on Thursday to meet US President Barack Obama.


A council has been criticised for plans to lend millions to an attraction owned by one of Britain's largest landowners.

Northumberland County Council intends to lend £8.5m to the Duchess of Northumberland's Alnwick Garden for a new play area.
The council said it needed to increase job numbers and support the economy.
Alnwick Garden said the money was a loan, not a grant, and the new "play structure for elves" would bring tourism and jobs.
Independent councillor Stephen Bridgett asked why Alnwick Castle and the Duke's Northumberland Estates could not pay for the new attraction.
"Why should the taxpayers of Northumberland be burdened with it?" he said.
The council needs to cut £6m from its budget this year and is looking at a possible council tax increase of 4.99%.
Labour council leader Grant Davey said the loan was "about jobs and the economy".
"We've got to boost the economy of Northumberland and we've got to increase the job numbers here in Northumberland," he said.
Alnwick Garden CEO Mark Brassell said the Play Garden would be "an international attraction to the UK and our region, bringing tourism, jobs, significant secondary spend and a measurable boost to the local economy".
The garden is run by a charitable trust but the Duke and Duchess of Northumberland are thought to be worth around £365m.
The Duke is listed by Country Life magazine and Tatler magazine as the country's fifth largest landowner, with 130,100 acres (52,650 hectares).
The council will discuss its budget plans on 22 February.


Introducing a form of the Rooney Rule to boost the number of black and ethnic minority coaches in England might be "a good way forward", believes Football Association chairman Greg Dyke.

The rule, set up in the United States in 2003, requires the NFL's American Football teams to interview minority candidates for head coaching positions.
Dyke said: "The FA inclusion advisory board is looking at it.
"I think there probably will be the equivalent [of the Rooney Rule]."
There are currently just three black managers at English football's 92 league clubs, while a recent study found just 19 BME coaches in 552 top coaching positions at professional English clubs.
And speaking at the University of Manchester, Dyke said: "The people running football all recognise there's a problem and that was probably not where they were two years ago.
"[The Rooney Rule] might be a good way forward."
Dyke said he hoped that there would be between 50 and 100 top-level BME coaches in England within five years.
"I think we will succeed," he said. "We're in the institutional phase where we know there's a problem and we have got to find the solutions."


Western Digital has resubmitted its bid for Toshiba's flagship flash memory unit amid a battle over the sale of the business.

The new offer is understood to be in the region of 2tn yen (£14bn).
Toshiba needs to sell the unit after an accounting scandal and cost overruns at its Westinghouse nuclear unit.
Western Digital, which jointly runs Toshiba's main semiconductor plant, has been feuding bitterly with its Japanese partner.
It has sought a US court injunction to prevent any deal that does not have its consent.
But Toshiba wants to sell to a different bidder.
The Japanese technology giant wants to nail down an agreement to sell to a consortium led by the Japanese government by Wednesday, the day of Toshiba's annual shareholders meeting.
The consortium, which includes Bain Capital, has previously offered around 2tn yen.
Western Digital has a 49% stake in the unit thanks to its joint venture with Toshiba, which has been in existence for 17 years.
The US company has said the deal grants both parties rights including consent to the disposal of assets.
The BBC has seen a letter sent by Western Digital's board to Toshiba in which they warn they "will not consent to a transaction with the proposed consortium" because of concerns over the involvement of South Korean rival SK Hynix, which they fear will try to benefit from the technology at stake.
"SK Hynix paid hundreds of millions of dollars to Toshiba just two years ago to settle claims that it misappropriated critical JV technology," the letter said.
"SK Hynix's participation in a consortium purchasing Toshiba's interests in the JVs increases the likelihood of technology leakage and harm to the JVs going forward," it added.
Toshiba wants to sell the unit quickly to cover billions of dollars in cost overruns at its bankrupt Westinghouse nuclear unit and to dig itself out of negative shareholder equity that could lead to a delisting.
Last week, Toshiba warned its losses for 2016 may be greater than it had previously forecast.
It predicted a net loss of 995bn yen (£7bn) for the year to March, up from its earlier estimate of 950bn yen.
The firm was demoted to the second tier of the Tokyo Exchange after confirming its liabilities outweighed its assets.
It also got regulatory approval to delay filing its annual earnings again, this time until 10 August, after a previous deadline extension to 30 June.


Andrew Crossley, the controversial solicitor who sent thousands of letters to alleged illegal file-sharers, has been suspended from the profession for two years.

At a disciplinary tribunal he was also ordered to pay costs of Â£76,326.55.
The court heard how Mr Crossley used his law firm ACS: Law to demand money in recompense for alleged copyright infringements.
The scheme unravelled when several cases went to court.
The Solicitors' Regulation Authority (SRA), which brought the case against Mr Crossley, welcomed the decision to uphold the allegations against Mr Crossley.
"Some of those affected were vulnerable members of the public and this matter has caused them significant distress," said an SRA spokesman.
"We hope that it serves as a warning to others. Solicitors have a trusted position in society and therefore have a duty to act with integrity, independence and in the best interests of their clients," he added.
It has taken two-and-a-half years for the case to come before the Solicitors' Disciplinary Tribunal.
The allegations included "acting in a way that was likely to diminish the trust the public places in him or in the legal profession" and "using his position as a solicitor to take unfair advantage of the recipients of the letters for his own benefit".
In mitigation, Mr Crossley said that he had already suffered as a result of the work he had undertaken and was now bankrupt. He said he was in danger of having his house repossessed and that his 15-year relationship had broken down because of the case.
Mr Crossley began the so-called speculative invoicing scheme in May 2009.
In total he sent about 20,000 letters to people identified as having downloaded content, often pornography, without paying for it. He claimed he was acting on behalf of MediaCAT, which in turn represented the copyright owners.
The letters threatened court action unless the recipient paid a one-off fee of about Â£500.
Consumer group Which? was one of the first to highlight the cases of people who claimed that they had been wrongly accused and had been upset by the threatening nature of the letters.
When a handful of cases came to court, the scheme came in for widespread derision, angering the presiding judge, Judge Birss, who turned the spotlight on Mr Crossley, accusing him of abusing the court process.
The lawyer for the defendants likened the case to Charles Dickens' Bleak House.
In a further twist, the ACS: Law website was hacked and huge amounts of sensitive data were exposed during attempts to get it up and running again.
Mr Crossley was fined by the Information Commissioner's Office for the data breach.
James Bench, founder of campaign group Being Threatened?, set up to represent those who received letters from ACS: Law, said he was pleased by the findings of the disciplinary hearing.
"The judgement will provide some satisfaction to those innocent members of the public that Mr Crossley relentlessly bullied in the operation of this scheme," he said.
"It was clear to all that Mr Crossley's speculative invoicing scheme lacked any legal merit," he added.
But he said that he was disappointed that the case had taken nearly three years to reach a conclusion.
It was revealed during the hearing that the SRA had asked Mr Crossley to stop the scheme within days of him setting it up, but he had refused.


Two police officers have been injured after their police car smashed into a streetlight following a collision with another vehicle.

The marked police car and a red Renault Clio collided on Aikenhead Road in Glasgow near Cathcart Police Office.
Both cars then hit a streetlight and bollard in the accident at about 11:25 on Sunday.
A Police Scotland spokesman said the two male police officers were taken to hospital by ambulance for treatment.
He added that neither were thought to have sustained any serious injury.
"The 59-year-old female driver of the red Renault Clio and her 35-year-old female passenger were also taken to the Queen Elizabeth University Hospital as a precaution," he said.
"The two male children in the car, aged 14 and three years, were not injured."
He said both cars sustained significant damage in the crash and inquiries into the accident were continuing.


Reading manager Jaap Stam admits he does not yet know his strongest side as he continues preparations for his first season in charge of the club.

Former Manchester United and Netherlands defender Stam, 44, succeeded Brian McDermott in June.
He saw a young Royals side beat Swindon 2-1 in a pre-season friendly on Tuesday after coming from a goal down.
"We need to have a big squad this season with quality, experience and young talent," he told BBC Sport.
"We have to look at everyone. We need to know the strongest XI, but also those who are going to give us depth in the squad.
Reading start their Championship campaign at home to Preston on 6 August and Stam is still undecided about who will line-up in the Madejski Stadium opener.
"We've a good idea, but we're still working on it," he told BBC Radio Berkshire.
"I'm not the type of manager who is going to pick 11 players and they will be the team for the season.
"I look at the opponent too and their qualities and what qualities we need on the pitch at the time.
"We're still working on a new system and how everyone knows how to implement it at the right moment."


Derby fought back to draw with Championship promotion hopefuls Huddersfield, a result that sent Brighton up to the Premier League.

Jacob Butterfield dented his former club's ambitions of reaching the top two with a deflected finish, leaving them seven points adrift of Newcastle.
In a first half of few chances, Collin Quaner put the visitors ahead when he converted Martin Cranie's cross.
Derby rarely threatened before Butterfield's late long-range effort.
Butterfield's goal two minutes from full-time leaves the Terriers fourth in the table - with a game in hand on all sides above them - but was not enough to salvage Derby's play-off aspirations as they slipped 10 points behind the top six.
The result added to the celebrations on the south coast as it meant Brighton were mathematically assured of top-flight return after a 34-year absence.
It also came as a relief to Newcastle supporters following their side's 3-1 defeat by Ipswich earlier in the day, as victory for Huddersfield would have moved them to within five points of the Magpies.
German forward Quaner opened the scoring after a fine team move and while Darren Bent did have the ball in the back of the net in response soon after, the goal was ruled out for offside.
Despite the draw now leaving Derby with nothing left to play for this season, it ensured Garry Rowett avoided a first home defeat on an afternoon that his controversial replacement at Birmingham City, Gianfranco Zola, resigned from his post.
Derby manager Gary Rowett: "We want more quality and penetration, but I'm pleased with the character of the team.
"We kept going and did not lose hope, you have got to keep doing the right things for the whole period and we got something out of the game.
"We showed plenty of patience against a tough team. We have got some quality players but the balance is not there."
Huddersfield head coach David Wagner: "If we secure a play-off spot then we will be very happy. We are humble and we know how difficult it is to get points in this division.
"We are Huddersfield Town and to have this points total is an unbelievable achievement. We have to focus on ourselves and not Newcastle.
"We are in a wonderful position but we do not have enough points yet. We would like to have more points and we would like more good performances."
Match ends, Derby County 1, Huddersfield Town 1.
Second Half ends, Derby County 1, Huddersfield Town 1.
Attempt missed. Nahki Wells (Huddersfield Town) right footed shot from the right side of the box misses to the left. Assisted by Aaron Mooy.
Foul by Darren Bent (Derby County).
Dean Whitehead (Huddersfield Town) wins a free kick in the defensive half.
Abdoul Camara (Derby County) wins a free kick in the defensive half.
Foul by Collin Quaner (Huddersfield Town).
Foul by Markus Olsson (Derby County).
Tommy Smith (Huddersfield Town) wins a free kick in the defensive half.
Hand ball by Chris Löwe (Huddersfield Town).
Goal!  Derby County 1, Huddersfield Town 1. Jacob Butterfield (Derby County) right footed shot from outside the box to the bottom right corner. Assisted by Ikechi Anya.
Attempt missed. Alex Pearce (Derby County) header from the right side of the six yard box is high and wide to the right. Assisted by Ikechi Anya with a cross following a set piece situation.
Michael Hefele (Huddersfield Town) is shown the yellow card for a bad foul.
Will Hughes (Derby County) wins a free kick on the left wing.
Foul by Michael Hefele (Huddersfield Town).
Foul by Markus Olsson (Derby County).
Jonathan Hogg (Huddersfield Town) wins a free kick in the defensive half.
Corner,  Huddersfield Town. Conceded by Cyrus Christie.
Foul by Johnny Russell (Derby County).
Dean Whitehead (Huddersfield Town) wins a free kick in the defensive half.
Substitution, Huddersfield Town. Jonathan Hogg replaces Joe Lolley.
Abdoul Camara (Derby County) is shown the yellow card for a bad foul.
Foul by Abdoul Camara (Derby County).
Nahki Wells (Huddersfield Town) wins a free kick in the defensive half.
Attempt missed. Darren Bent (Derby County) right footed shot from outside the box is too high from a direct free kick.
Johnny Russell (Derby County) wins a free kick in the attacking half.
Foul by Michael Hefele (Huddersfield Town).
Substitution, Derby County. Jacob Butterfield replaces Bradley Johnson.
Substitution, Derby County. Johnny Russell replaces Matej Vydra.
Substitution, Derby County. Abdoul Camara replaces Tom Ince.
Delay over. They are ready to continue.
Delay in match Nahki Wells (Huddersfield Town) because of an injury.
Foul by Tom Ince (Derby County).
Collin Quaner (Huddersfield Town) wins a free kick in the defensive half.
Substitution, Huddersfield Town. Nahki Wells replaces Rajiv van La Parra.
Foul by Will Hughes (Derby County).
Aaron Mooy (Huddersfield Town) wins a free kick in the defensive half.
Substitution, Huddersfield Town. Tommy Smith replaces Martin Cranie.
Delay over. They are ready to continue.
Delay in match Will Hughes (Derby County) because of an injury.


Uganda Revenue Authority (URA) FC - one of the country's biggest clubs - have encouraged their players to earn extra cash, by helping them to get into the lucrative motorcycle taxi business.

URA are helping the club's players to buy motorbikes, commonly known as boda bodas, which are widely used by businesses in Uganda to transport people and luggage.
With the cost of living continuing to rise in the Ugandan capital Kampala, club chairman Ali Ssekatawa told BBC Sport they no longer want their players to strictly rely on the income they get from playing football.
The club's management has, however, asked the players to hire riders and not to ride the motorbikes themselves, due to the risk involved.
Media playback is not supported on this device
"We are looking at a way of having a self-sustaining system and when our staff is sorted they can play well," Ssekatawa said.
URA FC are one of the most popular Uganda Premier League sides and have represented the East African country in the Caf Champions League and Confederation Cup competitions - Africa's biggest continental club competitions.
The numbers of boda bodas have recently ballooned in Kampala, but so have the number of accidents - rising eight-fold in the past eight years, with businesses looking at safer ways of operating the bikes.
Earlier this year URA FC's commissioner Doris Akol promised they would help the players with an alternative money-making venture and club chairman Ssekatawa delivered 17 motorbikes to the players at the club's training ground on Thursday.
Long-serving defender and Uganda international Simeon Masaba said he favoured the initiative, as it will help the players to earn extra income for their families.
"The club will be deducting our pay for some months so that we pay the percentage for the [running of the] motorbikes," Masaba said.
The defender added that although the motorbike business is risky, with thieves targeting the boda bodas, he thinks if managed well it could make a good small business for the URA footballers.
"This is a good move by the club and most of us are happy about it," striker Robert Ssentongo added.
Team coach Kefa Kisaala also received one of the bikes and said he was happy with the move.
However, attacking midfielder Saidi Kyeyune, said he did not agree with the initiative as he thinks it will be difficult to manage.


Canadian researchers have figured out a way to test just how much urine can be found in a swimming pool.

The results? In some cases, about 0.01% of pool water is urine.
It is a small amount but likely more than enough for most swimmers - and enough to be a public health concern.
In one instance, the researchers estimated that an 833,000-litre (220,000-gallon) pool could contain about 75 litres of urine (20 gallons) on average.
A smaller 416,000-litre (110,000-gallon) pool was estimated to contain 30 litres (eight gallons).
The University of Alberta researchers analysed more than 250 samples from 31 pools and hot tubs. The samples were collected in two undisclosed Canadian cities, from public and private pools, hotels, and hot tubs.
Dr Xing-Fang Li, with the University of Alberta's Department of Laboratory Medicine and Pathology, and her colleagues said recent instances - like the diving pools at the 2016 Rio Olympics turning green - highlight the importance of monitoring water quality.
The scientists used the amount of acesulfame potassium (ACE), a common artificial sweetener that passes that through the body and is excreted in urine, as a marker for their tests.
ACE was found in all the study samples and allowed them to roughly measure how much urine is actually in a pool.
Researcher Lindsay Blackstock says that "the only logical explanation for why it would end in swimming pools and hot tubs in such elevated levels is urine".
The team knew going into the study that though people do relieve themselves when swimming.
"Although considered a taboo, 19% of adults have admitted to having urinated in a swimming pool at least once," they note in the study.
When mixed with chlorine in a pool or hot tub, urine can contribute to the formation of so-called "disinfection by-products" in pool water that can be harmful to a swimmer's health.
Those compounds. specifically one called trichloramine, can potentially cause eye irritation, respiratory problems, and has been linked to occupational asthma for people who spend hours in pools, like pool workers and professional swimmers.
Ms Blackstock said cleaning chemicals like chlorine, which help stop the transmission of water-born pathogens, are not the problem - people are.
"If you're peeing in the pool, you're contributing to a potential health risk," she said.
Urine is not the only factor in the formation of those disinfection by-products - sweat, body lotions and hair care products contribute to the problem as well.
The Edmonton-based researchers suggested that a public health campaign focusing on pool hygiene, like taking a quick shower before jumping in the pool, might help reduce exposure to those disinfection by-products.
The research was published on Wednesday in the  Environmental Science and Technology Letters journal.


A dozen Scottish businesses have been named and shamed for failing to pay workers the minimum wage.

They were on a list of more than 100 employers identified by the UK government after investigations by HM Revenue & Customs.
Scottish firms named included a garage, a taxi business and five hairdressers.
UK business minister Nick Boles said employers that failed to pay the minimum wage "hurt the living standards of the lowest paid and their families".
The current national minimum wage is set at ??6.70 per hour for adults.
The biggest underpayment north of the border involved Village Garage Engineers Ltd, trading as Village Garage in Plean, near Stirling, which neglected to pay about ??9,150 to three workers.
Ian Balfour and Caroline Balfour, trading as Kirkcaldy-based A E Taxis, failed to pay more than ??4,750 to three workers.
Margaret Jankowitz, trading as The Beeches Hair Studio in Clydebank, neglected to pay about ??3,300 to three workers, while Paterson SA Hairdressing in Edinburgh failed to pay about ??3,200 to 15 workers.
Other Scottish businesses named included:
Overall, the 115 UK companies named owed workers more than ??389,000 in arrears. The firms spanned sectors including hairdressing, retail, education, catering and social care.
Since the name and shame scheme was introduced in 2013, 400 employers have been listed, with total arrears of nearly ??1.2m and penalties of about ??513,000.
Mr Boles said: "As a one nation government on the side of working people we are determined that everyone who is entitled to the National Minimum Wage receives it.
"Next April we will introduce a new National Living Wage which will mean a ??900-a-year pay rise for someone working full-time on the minimum wage, and we will enforce this equally robustly."


Jump racing moved into a new era following the retirement of AP McCoy last April, with Richard Johnson taking the opportunity to achieve a long-held dream.

Johnson was crowned champion jockey this weekend, having finished runner-up on 16 occasions - every time to McCoy, who won the title on 20 successive occasions.
Paul Nicholls was the top trainer for the 10th time in 11 seasons and, considering he had just two successes in valuable Grade One races, did tremendously well to hold on to the title ahead of Willie Mullins.
The Grand National, meanwhile, was won by Rule The World, ridden by 19-year-old David Mullins for trainer Mouse Morris.
As the first post-McCoy jump racing season draws to a close, here are my thoughts on the significant moments and achievements.
A public vote gave the jumps horse of the year accolade to Thistlecrack on Saturday. Yet the Colin Tizzard-trained eight-year-old - named after a field on the West Country farm of owners John and Heather Snook - did not win by the proverbial field, as a string of equine stars shone in what was a vintage campaign.
The undisputed champion of long distance hurdling, Thistlecrack beat off competition from a sparkling quartet of Annie Power, Tizzard's Cue Card, Don Cossack and Sprinter Sacre.
Anyone of the 'finalists' would have been the worthiest of winners, especially the remarkable Sprinter Sacre, who overcame a heart condition and severe loss of form to regain his Queen Mother Champion Chase title at the Cheltenham Festival. I hope they're all back for next season's marquee events.
Cue Card, already successful in the Betfair and King George VI Chases, was very much on course for the Jockey Club's new £1m 'Steeplechasing Triple Crown' when falling at the third-to-last fence in the Cheltenham Gold Cup.
We will never know what might have happened had the hugely-popular 10-year-old stayed on his feet, but his legion of fans were quick to note that, when making a triumphant return to the winners' circle at Aintree barely three weeks later, Cue Card had the Gold Cup's second and third-placed horses trailing in his wake.
However, Cue Card's unscheduled departure was not the season's only expensive one: had the Willie Mullins-trained Vautour won rather than crashing out - when cruising - of Aintree's Melling Chase, Mullins would have won £112,260 in prize money and beaten Paul Nicholls to be champion trainer. Ouch.
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Lizzie Kelly carved out a significant piece of horseracing history when becoming the first woman to ride the winner of a top-of-the-tree, Grade One jumps race in Britain when guiding Tea For Two to victory at Kempton on Boxing Day.
Only a few weeks later, Kelly - again riding for her trainer-step-father Nick Williams - landed Europe's richest handicap hurdle, staged at Newbury in February, on Agrapart.
There were further success in National Hunt races for the Ireland-based pair Nina Carberry and Katie Walsh and plenty of others. It means surely that the sport's perennial question - will a female jockey ever win the Grand National? - will be answered sooner rather than later, in the affirmative.
The idea has been mooted over recent weeks as Richard Johnson - 'Dickie' throughout jump racing - as it became clear that he was going to land his first title with a display of the same kind of ruthless dominance for which AP McCoy became famous.
The new champion, easily the second most successful jump jockey of all time, sailed by the 3,000-winner mark in January, but still needs 1,300 more to catch his old friend and rival, and by my maths, even at his current prolific rate, that would take five-and-half years. At 38, he's among the most senior members of the jockeys' changing-room.
So it is possible, but unlikely. Johnson has said it would have been lovely to have beaten McCoy, but he is now just concentrating on defending his crown; the bookies make him long odds-on to beat Aidan Coleman, Sam Twiston-Davies and Co once again.
The first two names are easy. Trainer Dan Skelton and his jockey-brother Harry, sons of Olympic gold medal-winning showjumper Nick, both reached a century of winners for the first time.
Dan is an former assistant to Paul Nicholls, The 10-time champion trainer is likely to have his work cut out to hold off future challenges to his title from Willie Mullins, but the skills he passed on to his protégé will ensure that the Skeltons are not too far behind.
Scotland-born Craig Nichol was the champion conditional jockey [jumps apprentice] and has made a big impression on the northern circuit, but the pendulum among the young riders is likely to swing south now, with David Noonan and Harry Cobden tipped as up-and-coming talents.
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The double Olympic cycling champion swept aside a torrent of sceptics and their brickbats to not only complete the course in the Cheltenham Festival's Foxhunters Chase, but also finish in a highly creditable fifth place.
That was an astonishing achievement for somebody, however accomplished a sportsperson in another field, to pull off from scratch in a little over 12 months, and amid so much media scrutiny.
Pendleton's participation and evident passion about racing has provided a major boost for the sport - especially the point-to-pointing circuit, where she did much of her training - and the fact that she plans to keep on going can only be a plus. With more practice, an even better big-race finishing position may soon be beckoning.


CCTV footage of ex-Russian spy Alexander Litvinenko before he is said to have been given a fatal dose of poison has been shown at his inquiry.

He is seen arriving to meet contacts Andrei Lugovoi and Dmitri Kovtun, who are suspected of poisoning him.
CCTV from London's Millennium Hotel also showed the suspects entering the toilets before Mr Litvinenko arrived.
"Extremely high readings" of a radioactive substance were found in the toilets, the inquiry heard.
Mr Litvinenko, who died of radioactive poisoning on 23 November 2006, is believed to have been given a fatal dose of polonium-210 on the first of the month.
The inquiry heard how Mr Lugovoi had arranged to see Mr Litvinenko on 2 November, but on the morning of 1 November he called the ex-KGB agent to rearrange for later that day.
Mr Litvinenko, who fled from Russia to seek asylum in the UK, agreed to the meeting, and went to see Mr Lugovoi after an appointment with security expert Mario Scaramella.
A CCTV still presented to the inquiry showed Mr Litvinenko in a distinctive blue denim jacket with light collar, walking with Mr Scaramella.
The inquiry heard that no traces of a radioactive substance were found on Mr Scaramella, but that there was a "high reading on one of the sleeves" of Mr Litvinenko's jacket.
Mr Litvinenko was then seen arriving in the foyer for the meeting with Mr Lugovoi and Mr Kovtun at around 16:00 GMT.
Further footage showed the two men separately using toilets near the Mayfair hotel's Pine Bar - which is not covered by CCTV - in the half-hour before Mr Litvinenko arrived.
Asked why this was significant, Detective Inspector Craig Mascall said: "Because extremely high readings were found in the men's toilets."


England's all-time leading goalscorer Wayne Rooney has retired from international football after turning down the chance to be part of the squad for next month's World Cup qualifiers.

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The Everton striker was asked by England boss Gareth Southgate to be involved against Malta and Slovakia.
"Every time I was selected was a real privilege but I believe now is the time to bow out," said the 31-year-old.
The former Manchester United captain scored 53 times in 119 internationals.
Rooney, overlooked by Southgate for matches against Scotland and France in June, made his England debut in February 2003, in a 3-1 defeat by Australia at Upton Park.
He made his major tournament debut as an 18-year-old at Euro 2004, and his last international appearance was as captain in last November's 3-0 victory over Scotland at Wembley.
Rooney rejoined boyhood club Everton in the summer, and his announcement comes two days after he scored his 200th Premier League goal in a 1-1 draw at Manchester City.
After that game, he said he was "focusing on Everton" rather than an international recall.
"I'm sure I'll speak to Gareth Southgate over the next few days," he added. "We'll see what happens."
Southgate is due to name a squad on Thursday for the World Cup qualifiers in Malta on 1 September, and at home to Slovakia three days later.
It was great Gareth Southgate called me this week to tell me he wanted me back in the England squad for the upcoming matches. I really appreciated that.
However, having already thought long and hard, I told Gareth that I had now decided to retire for good from international football.
It is a really tough decision and one I have discussed with my family, my manager at Everton and those closest to me.
Playing for England has always been special to me. Every time I was selected as a player or captain was a real privilege and I thank everyone who helped me. But I believe now is the time to bow out.
Leaving Manchester United was a tough call but I know I made the right decision in coming home to Everton. Now I want to focus all my energies on helping them be successful.
I will always remain a passionate England fan. One of my very few regrets is not to have been part of a successful England tournament side. Hopefully the exciting players Gareth is bringing through can take that ambition further and I hope everyone will get behind the team.
One day the dream will come true and I look forward to being there as a fan - or in any capacity.
BBC Sport's chief football writer Phil McNulty
Rooney retires from international football as England's record goalscorer - and perhaps with his contribution undervalued.
The 31-year-old's career was a mixture of highs and lows after he truly burst on the global scene as a teenager at Euro 2004, and Rooney will forever be associated with an outstanding group of club players who could not replicate their domestic and European success at international level.
Rooney did not score at a World Cup until his third attempt - eventually netting against Uruguay in Brazil in 2014 - but he was also a player who carried England on so many occasions and his place in the history books is testimony to his outstanding contribution over so many years.
He performed selflessly, often in unfamiliar roles, and his commitment was unquestioned. For all the occasional demands for Rooney to be dropped during his England career, there was rarely much proof they would have been a better team without him.
England's lack of success during his time on the international scene will always be a source of frustration and regret, but history may be kinder to Rooney on reflection upon an stellar career.
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Former England striker Alan Shearer, who announced his own international retirement at 29, said that Rooney's club career would benefit.
"Everton will benefit hugely I'm sure because he won't be flying around the world playing in tournaments, qualifiers and the rest," he told BBC Radio 5 live.
"Instead he will be sat at home having a rest and coming into training energised rather than stiff and tired from playing aboard and travelling back."
Ex England manager Roy Hodgson made Rooney his captain in August 2014 following Steven Gerrard's retirement and said the forward relished the responsibility.
"He was very good with me and the rest of the staff in putting across our messages to the players and keeping us informed on everything that was happening," he told BBC Radio 5 live.
"Most importantly, he was very good with the younger players. He is older but he has the ability to bond with them.
"He is a great patriot and he could not wait to put the shirt on.
"If we ever thought it was good for him to have a rest we had to wrestle with him and impose it upon him. If it was up to him, he would play every minute, every second!"
Former England and Manchester United teammate Phil Neville says Rooney's international retirement is a "sad day" as he is England's "greatest ever goalscorer".
"I remember when he first got into the squad - the youthfulness, the bravery, the courage that he showed, particularly in his first major tournament at Euro 2004," Neville told BBC Radio 5 live.
"He was a breath of fresh air. No-one enjoyed playing for England more than Wayne Rooney."
Neville added: "It's obviously a day we should be celebrating but also it's a sad day, losing one of our finest ever players. He's definitely the greatest goalscorer we've ever had.
"Now I hope he gets the send-off and the plaudits that he deserves."
Former England manager Sven-Goran Eriksson, who gave Rooney his debut, said he was surprised by the decision.
Speaking to BBC World Service, he said: "If he goes on playing like he is now, scoring goals for Everton, then he could still have been an important player for England, with the World Cup less than a year away.
"If I was the England manager, I would have done everything to convince Rooney to play at the World Cup and then make a decision."
Eriksson, who was England boss from 2001-2006, added: "I remember when training was finished Rooney didn't want to leave the training ground, he wanted to stay and do free-kicks, shooting etc. He loves his football and that is why he became what he became."
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A man and teenage boy arrested on suspicion of shooting a swan with a crossbow have been released without charge.

George, a male swan, was seriously injured when he was shot in the head in Pittville Park, Cheltenham, in January.
A 48-year-old man and 15-year-old boy, both from Cheltenham, were arrested a short time later.
Gloucestershire Police questioned the pair but officers believe they were not involved with the incident.
A force spokesman said no further action was being taken against them and renewed an appeal for any witnesses to come forward.
The swan, along with his breeding partner Zelda, has lived on Pittville lakes for a number of years.
The critically ill bird was found by a member of the public with a bolt lodged in his left eye.
It was treated at Vale Wildlife Hospital and Rehabilitation Centre and has now been released back to the lake.
A fundraising campaign raised more than Â£6,000 to pay for George's treatment and a reward to catch the person responsible.


The former head of Sierra Leone's army, Major-General Nelson Williams, has been kidnapped in Nigeria, reportedly in the northern Kaduna state.

Maj-Gen Williams, Sierra Leone's Deputy High Commissioner to Nigeria, was believed to have been travelling there for a ceremony at a military base.
Police say it is unclear where he was kidnapped and taken or if he was travelling in convoy.
Kidnapping for ransom is common in some parts of the country.
Africa Live: More on this and other news stories
The BBC's Martin Patience in Lagos says the abduction of a senior diplomat will be hugely embarrassing for the Nigerian government.
It is understood there has been a demand for a ransom, but it is not yet known who the kidnappers are.
Sierra Leone's information minister said the Nigerian authorities had assured him they were doing all they could to rescue Maj-Gen Williams.


A motorist has been found not guilty of two driving offences following a crash in which a cyclist died.

Amir Hussain, 61, of Horsham Road, Dorking, was cleared of failing to stop at the scene of a car crash and failing to report the accident in Surrey.
Mountain biker Robert Worrall, 30, from Beare Green, died at the scene of the crash on the A24 in the village at 01:25 GMT on 9 November 2014.
Mr Hussain was acquitted after a two-day trial before Guildford magistrates.
Gardener Mr Worrall, who worked at Dorking grounds maintenance company Groundscapes, was also a keen snowboarder.


At the Anteb restaurant in Yerevan, run by Syrian Armenians, all tables are booked, and there is a queue of people waiting outside.

They do serve good food here but the reason the place is packed is because there are many visitors in town.
They are diaspora Armenians from different parts of the world who have come to mark the centenary of what they call Meds Yeghern or the Great Catastrophe - the mass killings of ethnic Armenians in Ottoman Turkey.
Most of them are descendants of the survivors of the 1915 killings.
Krikor Krikorian, in his 70s, is from the UK and is dining with his English wife.
"The Armenians are like Irish, there are seven million of them living outside the country and just over two and a half million here," he says.
"My grandmother was from western Armenia, eastern Turkey. She had it extremely badly, she lost all her family, they were slaughtered.
"Two of her children were dying and she threw them over the bridge into the Euphrates river. They could have never walked to Syria - they could not have survived."
Krikor's grandmother did survive but on her deathbed she was still remembering Armenia.
"'If you ever make any money, don't forget Armenia,' these were her words to me."
Krikor fulfilled that pledge and is now involved in a charitable organisation that helps Armenian families in need.
"You can't find an Armenian family which did not suffer as a result of the events of 1915," says the Yerevan-based journalist Mark Grigorian.
"I am doing a TV programme now in Yerevan, I could not have imagined how many stories came out about the families that moved, that were trying to escape from genocide.
"It is still a huge trauma, we are talking about third, fourth generations of those who survived and even they are burning from this trauma deep inside."
The purple forget-me-not is the symbol of the centenary. It can be seen everywhere in Yerevan: from shop windows and windscreen stickers, to lapel pins that many are proudly wearing.
There is also a centenary slogan which reads: "I remember and demand".
But what is it that the Armenians are demanding? I asked some of the people in Yerevan's Mashtotz Avenue.
"We demand fairness from the world community, that's it," says Sergey Martirossyan.
"But for me personally it won't make any difference, what we actually need in Armenia is for the government to take serious steps towards economic growth."
Fourteen-year old Natalia is wearing a black T-shirt with giant 1915 digits in red and a slogan in Armenian.
"The slogan says that our wounds are still bleeding," she says.
On Friday, tens of thousands pay their respects at the memorial in Yerevan. A few days ahead of the commemoration ceremonies, there was already a sea of flowers, and people kept coming with more.
They are young and old, diaspora Armenians and locals - all united in their collective memory of injustice. And time has not healed their wounds.


Something strange has happened to Formula 1 in Germany.

The German Grand Prix was once a cornerstone of the calendar, a historic race on a unique and special circuit, packed out with enthusiastic spectators. But that status is under serious threat.
For one thing, the demise of the Nurburgring - which shared the hosting duties - means the event is held only once every two seasons. And its future beyond the end of Hockenheim's current contract in 2018 is uncertain to say the least.
The German GP used to be overrun with fans - and not just in the Michael Schumacher era; way before then, too, going back decades, from the golden days of the old Nurburgring and its 14 unbelievable miles and 180-odd corners through the Eiffel forests, and into the Hockenheim era.
Now, though, the race seems to have lost its appeal.
The last time it was held, in 2014, only 50,000 or so fans turned up - and Hockenheim's atmospheric concrete 'stadium' section, which used to be packed, was dotted with gaps.
This year, organisers are hopeful of reaching the 60,000 they need to break even. But that's still less than half the numbers who thronged Silverstone for the British Grand Prix earlier this month.
Is it down to seven-time champion Schumacher's absence? If so, what did the German fans find so alluring about him that they do not now about four-time champion Sebastian Vettel, title challenger Nico Rosberg and a dominant home Mercedes team?
Is it part of the perceived general decline of F1's appeal to younger audiences? If so, why are crowds going up at Silverstone, and staying strong at other historic venues, such as Italy, Canada and Brazil? And why are German TV figures rising, not declining?
Or is it that Hockenheim has had it character largely removed, with its long, flat-out blasts out into spooky pine forest replaced by yet another characterless 'Tilke-drome' from Bernie Ecclestone's favoured track architect?
It's not a completely terrible race track. The long, curving straight between Turns Two and Six provides for decent overtaking opportunities, there are a couple of demanding fast corners and the racing is usually OK, sometimes very good.
But it lacks spirit, challenge, jeopardy and, most of all, a sense of specialness - a reason to be excited. Just as, to a lesser extent, did Magny-Cours before the French Grand Prix - the oldest race of all - dropped off the calendar after 2008.
Is Germany going the same way? One has to hope not. But keeping it on the calendar will not be easy.
Andrew Benson, Chief F1 Writer
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Three tram lines could be built in Birmingham, alongside high-speed bus routes, under a £4bn transport plan.

The city council's 20-year Birmingham Connected scheme also includes details for reopening rail lines and building two new stations.
It said it did not currently have "all the funding in place".
Bids are expected to be made for government and European money, but local businesses could also make an "increased contribution".
This could take the form of additional "ring-fenced" taxation on businesses or additional business rates, Birmingham City Council said.
Jerry Blackett, chief executive of Greater Birmingham Chambers of Commerce, said transport had been a "key issue" for the city and that "inner-city travelling is fraught with congestion and poor public transit coverage".
He said businesses needed "clarity" on how the plan would be funded and that "blunt instruments" such as a parking levy - a tax on firms with parking spaces - could "stifle economic growth" in the city.
The council said it would also look at the "long-term future" of the A38 through the city centre, including closing existing tunnels and sending traffic along a "substantially upgraded ring road".
Sir Albert Bore, leader of Birmingham City Council, said that could take the form of joining up the tunnels or even creating a motorway under the city.
Dr Pat Hanlon, a transport expert at the University of Birmingham, said a "supertunnel" could not only improve congestion, but open up parts of the city for building, allowing key areas such as Great Charles Street and the Colmore business district to be joined up.
Dr Hanlon said in terms of transport Birmingham had "lost an awful lot of ground to Manchester" in particular.
More than one million car journeys were made into Birmingham each day, the council said, and the current public transport system meant commuters had "no real alternative" to driving.
The council estimated by 2031 there could be an additional 80,000 cars in the city if nothing was done.
The council also wants to reopen and upgrade rail routes to Moseley, Kings Heath and Sutton Coldfield, with new stations at Fort Parkway and Castle Vale.
A low emissions zone is planned for the city centre, with incentives for taxis and buses to switch to electric power.


Thai authorities say they have detained a monk attempting to smuggle tiger skins and fangs from a Buddhist temple.

Operators at Wat Pha Luang Ta Bua temple, known as the "Tiger Temple", are accused of wildlife trafficking and animal abuse. They deny the charges.
On Wednesday, wildlife officials found the bodies of 40 dead tiger cubs at the temple complex.
The discovery came during a week-long effort to relocate 137 tigers from the tourist site in Kanchanaburi province.
The temple operators had resisted previous attempts to remove the tigers.
Tiger Temple's long history of controversy
BBC visit to the Tiger Temple in 2012
Police intercepted the monk, and two other men, in a lorry leaving the temple in western Thailand on Thursday.
The authorities confiscated two full-length tiger skins, about 700 amulets made from tiger parts, and 10 tiger fangs, Teunchai Noochdumrong, director of of the Wildlife Conservation Office, told the BBC.
"This confiscation shows that the temple is likely involved in illegal tiger trade. They are clearly violating the law in selling, distributing of transferring the protected animals or their parts," she said.
Wildlife authorities in Thailand have said they will press charges against the temple.
On Wednesday, tiger cub corpses were found in a freezer at the complex, along with body parts from other animals.
Police Col Bandith Meungsukhum told the Agence France-Presse news agency the cubs would have been one or two days old, but it was not clear how long they had been dead.
They will be DNA tested to see whether they were related to other tigers at the site.
Officials say the temple operators could be charged with keeping the carcasses without permission.
The temple previously said it had decided in 2010 to stop cremating cubs which died soon after birth. It has always denied trafficking allegations.
Authorities started the operation to remove all 137 living tigers from the temple on Monday. Dozens have already been removed, and taken to animal refuges.
The site, west of Bangkok, is a popular tourist attraction, with visitors able to pose for photos with the animals for a fee.
It has been closed to the public since the raid.
Animal activists and former workers have claimed the tigers are mistreated and kept in small concrete cages.


The managing director of the Sandwich Company in Londonderry has said his staff are lucky to have escaped injury after a release of gas on Monday.

Twelve people were taken to hospital as a precaution after an underground cable caught fire, releasing carbon monoxide outside the shop on Spencer Road.
The Northern Ireland Fire and Rescue Service said it received a report of a smell of gas at about 12:20 BST.
The 12 people have since been released from hospital.
Joe Kincaid, the managing director of the Sandwich Company, told BBC Radio Foyle that the situation could have been worse.
"My staff were quite unsure about what was happening at the beginning.
"We have one staff member who lives in the apartment above the shop and he felt quite nauseous.
"You don't realise with these cables underneath the ground what can happen."
Kieran Doherty, district commander with the Northern Ireland Fire and Rescue, has said there could have been fatalities if this incident had happened at night.
"As a matter of procedure we always bring our gas monitors and straight away picked up large quantities of carbon monoxide.
"The amount we picked up would have been life-threatening.
"We then evacuated the premises."


British Basketball League side Plymouth Raiders have parted company with head coach Jay Marriott.

He will be replaced by Australian Daryl Corletto in a player-coach role.
The club are currently bottom of the table after losing all three of their matches and were knocked out of the BBL Cup in the first round after an 88-77 loss to Bristol Flyers.
Marriott was in charge of the Raiders for two years having replaced Gavin Love early in the 2013-14 season.
"If we are serious about making a run at a respectable league position this season, something had to be done now," said Raiders chairman Bob Widdecombe.
"We have only played three league games, which is one of the fewest of any of the teams in the league.
"We didn't want to sit back and allow half of the season to slip away.
"We now have to turn to Daryl and give him the support that he needs in order to lead this team back towards the top of the table."
The Raiders failed to make the play-offs in either of Marriott's years in charge.
Under his leadership, Plymouth did, however, reach the semi-finals of the 2013-14 BBL Cup and the same stage of last season's BBL Trophy.
Corletto joins the Raiders from Australian side Melbourne United, having won four titles in Australia.
"I want to work with the club's owner and management team to change the culture around the team, get the support back from the fans and sponsors and make the Raiders the team to challenge the dominance of Leicester and Newcastle in recent years," he said in a statement.


Heard about the Premier League newcomer who has represented his country in another sport?

How about the World Cup player who turned a social media campaign against him into a business? And which lower league signing impressed Wayne Rooney on a television programme?
These are just some of the more unusual snippets about players bought by British clubs in the January transfer window.
Here, BBC Sport picks 10 stories that have caught the eye:
Matt Grimes (Swansea City, £1.75m from Exeter City)
The 19-year-old midfielder is a national champion in ultimate frisbee. He was voted most valuable player in the 2011 final and has represented Great Britain in the sport.
Find out more (Exeter Express & Echo, and AirBadgers website)
Victor Valdes (Manchester United, free agent)
The former Barcelona goalkeeper's love of the ocean prompted him to give his first-born child the Welsh name Dylan, which translates as 'great tide'.
Find out more (Con la roja)
Miguel Layun (Watford, undisclosed fee from Granada)
The attacking left-back had the hashtag #TodoEsCulpaDeLayun (It's all Layun's fault) embroidered on his football boots as a reminder of the barrage of criticism he received for years from Club America fans on social media. He has now turned the hashtag into a clothing brand.
Find out more (Fifa)
Eljero Elia (Southampton, loan from Werder Bremen)
His unusual first name is the phonetic spelling of his sister's favourite jazz musician, American multiple Grammy Award winner Al Jarreau.
Find out more (FourFourTwo)
Andrej Kramaric(Leicester City, £9m-plus from Rijeka)
Croatia boss Niko Kovac has said the forward "throws the whole stand off balance" with his dribbles, and one piece of fancy footwork by Kramaric put opposition defender Lee Addy in hospital last February with a ruptured cruciate ligament.
Find out more (FourFourTwo)
Darvydas Sernas (Ross County, free from Wigry Suwalki)
The Lithuania international's debut as a substitute for Australian side Perth Glory last season was delayed as he was deemed to be wearing illegal socks and had to change them.
Find out more (Sportal)
Wilfried Bony (Manchester City, initial £25m from Swansea City)
The Ivorian can speak fluent Czech.
Find out more (Daily Mail)
Jermaine Hylton (Swindon Town, free from Redditch United)
The striker, now 21, reached the final of Wayne Rooney's Street Striker TV programme in 2009.
Find out more (Birmingham Mail)
Jordon Mutch (Crystal Palace, initial £4.75m from QPR)
Mutch was denied the chance to become the youngest player to appear in the League Cup, aged 15 years and 298 days, in 2007 when his then club Birmingham City were told of a new FA ruling forbidding under-16s to play senior football.
Find out more (Daily Telegraph)
Dele Alli (Tottenham, £5m from MK Dons)
His first touch of the ball on his professional debut was a cheeky back-heel to an MK Dons team-mate in an FA Cup tie against Cambridge City.
Find out more (BBC Sport)
Compiled by Noel Sliney, Katie Wright and Sophie Brown.


Wasps have confirmed their first game at the Ricoh Arena will be the Premiership meeting with London Irish on Sunday, 21 December.

The traditionally London-based club are moving 82 miles north of their current High Wycombe home to play in Coventry.
Nearly 3,000 people have signed a petition to protest against the move, which has seen the club buy a 50% stake in the Ricoh Arena as part of the deal.
Coventry City will continue to play there still as tenants of the stadium.
Wasps chief executive Nick Eastwood has previously described the move as a "watershed moment" in the club's history.
The club were reportedly an hour from administration when businessman Derek Richardson took over last year, but they continue to lose £3m a season playing at Wycombe Wanderers' Adams Park ground, and Eastwood has said the move will secure the long-term future of the team.
Wasps have played at Adams Park in High Wycombe for the past 12 years.
Coventry already has a long-established rugby union club, Coventry, which was formed more than 130 years ago and currently plays in National League One.
The city's councillors supported a deal to sell the authority's share in ACL - the company that runs the Ricoh Arena - to the Premiership club.
The council said the move guaranteed Coventry City Football Club's continuing tenancy at the stadium.
The football club, who recently returned to the stadium after a two-year dispute over rent, would also have "primacy over match fixtures", it added.


The proportion of women working into their 70s has doubled in the past four years, to 11%, according to official figures.

The claim: The increase in women working in their 70s is because some of them can't afford to retire.
Reality Check verdict: Although some women keep working out of choice, it is also likely that others are doing so because increased life expectancy and an inadequate pension pot means they don't have enough money to retire on.
That works out as about 150,000 women still working into their mid-70s.
Although the growth has been strong, there is still a higher proportion of men working into their 70s, at 15.5%.
But are some women continuing to work later in life because they want to, or because they cannot afford to retire?
Life expectancy has been steadily climbing in the UK, and a woman who was 65 in 2015 could expect to live a further 20.9 years, on average, according to the Office for National Statistics (ONS).
A longer life expectancy is, of course, good news, but also means this generation requires a higher level of savings to cover living expenses, not to mention possible care costs.
The Joseph Rowntree Foundation puts the minimum income standard for pensioners at £186.77 a week - the equivalent of £9,712 a year.
But a pensioner retiring after April 6 this year and relying purely on their state pension will have an income of £8,300 per year - £1,400 less than the Joseph Rowntree estimate.
This means retirees also need to have built up their own pension pot.
A survey from the pension provider Aegon suggests the average woman has less than half of the retirement savings an average man has.
It also indicated the average woman hoped to retire at 64, compared with 65 for men.
There are a number of factors behind this disparity.
Women have a higher life expectancy than men, and on average earn less over the course of their working lifetimes as they are more likely to have taken time out from work for caring responsibilities.
What's more, one in three women currently earns less than £10,000, which is the threshold at which they are eligible for automatic enrolment into a private pension scheme.
Changes to the state pension age have also played a part.
Until 1995, women expected to draw their state pensions at 60; men at 65.
But changes made by the 1995 Pensions Act meant the pension ages of both men and women would be 65 by 2020.
In 2011, this changed again, meaning some women born between April 1951 and 1960 are now facing a pension age of 66.
The Cridland Report on the state pension age is due out on Thursday.
Action group Women Against State Pension Inequality (Waspi) was set up to campaign for transitional arrangements for women born in the 1950s who have been negatively affected by changes in state pension law.
The group says hundreds of thousands of women are suffering from financial hardship as a result of the changes, with not enough time to re-plan for their retirement.
Read more from Reality Check


A former BBC presenter has told a court he found watching his wife with a young stranger "erotic".

Tony Wadsworth said his wife Julie was, "a very special human being" who had found the daytime encounter in a Warwickshire woodland "exhilarating".
The couple are on trial at Warwick Crown Court accused of assaulting seven boys in the 1990s.
Mrs Wadsworth accepts having sexual encounters with "young men" but has repeatedly denied they were under age.
The husband and wife duo were employed in BBC local radio at the time of the alleged offences.
Giving evidence in his defence, Mr Wadsworth described two separate encounters involving up to three males each time.
He told the court they appeared to be "16, 17 - possibly 18".
Mr Wadsworth described a claim he had illegal sexual encounters as "outrageous", and denied a prosecution allegation he had a threesome with his wife and a boy at his then home in Warwickshire.
When describing the couple's first encounter in the woods with one of the complainants, Mr Wadsworth said he found it "erotic" to watch his wife with the young stranger.
"She felt empowered as a woman," he said.
He claimed he and his wife had been "kissing and cuddling" when they became aware of a young man watching them.
Mr Wadsworth, 69, said: "I turned, looked around and saw this fella and must confess it was something of a shock.
"It was clear what he was hoping to do. He came forward as I stepped to one side."
He said the encounter took place without a word being exchanged.
He said: "After the heat of the moment was over, it was all very embarrassing and awkward.
"We tidied ourselves up and we all went our separate ways."
Asked by his barrister Michelle Clarke why he allowed his wife to be approached by another man, Mr Wadsworth said her past with an abusive partner had left her insecure.
He told jurors he wanted to prove others found her sexually desirable.
"I think it's fair to say that Julie was and to some extent still is today a damaged person," he said.
"And as our relationship developed she began to confide in me and tell me about her abusive partner who was absolutely vile - the things he perpetrated on her.
"So I did my best to bring out the woman inside her, I suppose."
Mrs Wadsworth has accepted going on to have a sexual relationship with the first complainant, after bumping into him some years later.
Her husband said he was angry when he discovered that tryst and rejected a Facebook friend request from the complainant in 2015.
He said the couple  - who previously worked for BBC Leicester and Birmingham-based BBC WM - had taken part in a second woodland encounter involving three males.
Afterwards he said the couple agreed what was happening was "ridiculous, foolhardy and stupid and there would be no repetition".
The couple, from Broughton Astley, Leicestershire, deny five counts of outraging public decency which allege they engaged in sexual activity "against a tree" in view of others between July 1992 and June 1996.
Mrs Wadsworth has pleaded not guilty to 11 charges of indecent assault, while her husband denies nine counts of the same offence.
The trial continues.


A British warship has rescued hundreds of migrants from the Mediterranean, the Ministry of Defence has said.

HMS Bulwark brought more than 400 people to safety after they were found 40 miles from the Libyan coast in inflatable boats.
The European Commission has proposed a scheme to offer 20,000 refugees the right to resettle in the EU.
Meanwhile, Home Secretary Theresa May has suggested that some rescued migrants should be returned home.
The BBC defence correspondent Jonathan Beale said a further 150 migrants had been transferred to HMS Bulwark from an Italian coastguard vessel and the ship would now head to Sicily.
Defence Secretary Michael Fallon said the Royal Navy had rescued about 600 people so far this month.
The Ministry of Defence said HMS Bulwark had been alerted to four 30ft boats in potential distress, each carrying about 100 people including pregnant women and children.
Captain Nick Cooke Priest, commanding officer of HMS Bulwark, said people on the "precarious" boats were suffering from dehydration and injuries.
"The weather at the moment is extremely hot so my ship's company and I are very pleased that we were able to bring them to safety," he said.
To help combat the migrant crisis, the European Commission has proposed the new resettlement scheme, which will take place over the next two years.
By the end of May, it also plans to introduce a temporary mechanism for distributing thousands of migrants already in Europe among EU member states.
But Mrs May said offering resettlement regardless of circumstances to migrants rescued from the Mediterranean would encourage more to make "perilous journeys".
This was why the UK was not backing a resettlement quota plan, she said.
Mr Fallon said HMS Bulwark had already proved to be an "invaluable asset in assisting with the Mediterranean migrant crisis".
"The ship is providing medical assistance, food, water and dry clothes to those in need and will transfer them safely to land as soon as possible," he said.
The UN estimates that 60,000 people have already tried to cross the Mediterranean from North Africa this year.
More than 1,800 migrants have died - a 20-fold increase on the same period in 2014.
France, Germany, Italy and some other countries have backed the quota proposal, but a majority of EU governments would have to agree for it to become law.
As things stand, the UK could decide to opt in to the scheme, but could not be compelled to join, as it has the power to opt out of justice and home affairs policies set by the EU - and asylum decisions are included in that opt-out.
The Home Office has instead urged the EU to focus on combating people traffickers.


Germany's Angelique Kerber became the first women's top seed to lose in the opening round of the French Open with defeat by Ekaterina Makarova.

Kerber went down 6-2 6-2 in one hour and 22 minutes, leaving her number one status in the balance.
Both Simona Halep and Karolina Pliskova have the chance to take top spot for the first time with good runs in Paris.
However, Halep is recovering from injury and Pliskova fell in the first round last year.
That is symptomatic of the uncertainty in the women's draw that led Halep to claim up to 15 players are in with a chance of winning the title.
Kerber, a first-round loser last year as well, barely figured among the favourites on the eve of the tournament.
Although her defeat might have been a shock in terms of rankings, with Russia's Makarova at number 40 in the WTA standings, it was no great surprise.
The 29-year-old from Bremen has been struggling for form this year, reaching just one final and winning only three matches on clay heading into Roland Garros.
Kerber only regained the number one ranking from Serena Williams after the American stepped away from the tour as she awaits the birth of her first child.
I have to try to forget the clay-court season as soon as possible
While Kerber fully merited that status last year, when she won the Australian and US Opens, the German arrived in Paris ranked 13th for the year so far.
The superb footwork, tenacity from the baseline and all-round aggressive defence that took her so far in 2016 have deserted her in 2017.
That has left her old frailties exposed, with a weak serve broken six times by Makarova on Philippe Chatrier Court.
After falling 5-1 down on her way to losing the first set, Kerber rallied late in the second, but the clinical edge has also gone from her game.
A final tally of just two break points converted from 16 illustrated that lack of certainty in the key moments.
"Last year was a completely different year," said Kerber. "The pressure is always there but this year the expectations are much bigger, especially in the big tournaments and the Grand Slams.
"And the expectations are also from me really big, of course, because I know what I can do, what I did last year.
"But right now I think I have to find myself again and just try to forget the clay-court season as soon as possible and then reset and start from the grass courts again."
Makarova, 28, goes on to face Ukraine's Lesia Tsurenko in round two, and will feel she has as good a chance as anyone to feature in the latter stages.
American Venus Williams beat China's Wang Qiang 6-4 7-6 (7-3) on the 20th anniversary of her debut at Roland Garros.
The 10th seed hit 44 unforced errors in an untidy display but goes on to face Japan's 90th-ranked Kurumi Nara.
Nara beat American wildcard Amanda Anisimova who at 15 years and nine months is the youngest player in the women's main draw since France's Alize Cornet in 2005.
Anisimova, ranked 267, won the first set but Nara fought back to win 3-6 7-5 6-4.
When Venus lost her only French Open final appearance in 2002 to sister Serena, Anisimova was just nine months old.


A senior leader of the Muslim Brotherhood organisation has been killed by Egyptian Interior Ministry forces, the ministry says.

In a statement, it said Mohamed Kamal died in a gun battle along with another member of the group on Monday.
The ministry said Mr Kamal was in charge of the group's armed wing, although the Brotherhood maintains it is a exclusively peaceful organisation.
He had been sentenced to life in prison on two counts in absentia.
The Muslim Brotherhood said he had disappeared on Monday.
Profile: Egypt's Muslim Brotherhood


England striker Toni Duggan has signed for Barcelona from Manchester City Women on a two-year contract.

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The 25-year-old former Everton Ladies forward is the first English player to join the Catalan club since Gary Lineker's move to the Nou Camp in 1986.
Duggan has scored 15 goals in 47 senior appearances for England and is part of their squad for Women's Euro 2017.
BBC Sport understands no transfer fee was exchanged, as Duggan's contract had been set to expire in November 2017.
After arriving from Everton in November 2013, Duggan helped City win the Women's Super League One title for the first time in 2016 and was part of the squad that won this year's Women's FA Cup.
She was also part of the England side that finished third in the 2015 Women's World Cup in Canada.
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"FC Barcelona are known all over the world for playing attractive football and I naturally wanted to be part of that," Duggan said. "I think my style of play will suit the team and I'm honoured to be part of the club.
"My new coach Fran Sanchez has told me that their ambition is to win the Women's Champions League and the club have made that very clear with their signings over the years.
"I've had a lot of success in England and I've really enjoyed my time with Manchester City but I wanted to challenge myself even further by playing abroad. I'm also looking forward to learning Spanish and living in the city."
Like City, Barcelona reached the Women's Champions League semi-finals for the first time in their history in 2016-17, and finished second in the Spanish top flight last term.
They have increased their investment in women's football markedly in recent years, re-signing Spain midfielder Vicky Losada from Arsenal in November.
Barcelona are in talks with the American National Women's Soccer League about entering a team for 2018, having opened a permanent office in New York in September.
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The NWSL has never previously included a European side but is fully professional, in contrast to the Spanish top tier, which includes some semi-professional sides.
Duggan scored four goals in four league appearances in the 2017 Spring Series and a fine individual goal in the Women's Champions League.
The Liverpool-born striker will become the only member of the current England Women squad to be based abroad.
In total, she scored 31 goals in 74 appearances for Manchester City.


A man has appeared in court after two police officers were injured in an attack.

The pair were hurt while attending a "domestic incident" in Aldershot in Hampshire on Tuesday, police said.
Simon Priest, 41, of Pegasus Avenue in Aldershot is charged with causing grievous bodily harm, attempted GBH and possession of a firearm.
He was remanded in custody by Basingstoke magistrates to appear at Winchester Crown Court on 15 March.
Mr Priest also faces charges of escaping lawful custody and theft of a police Taser.
One officer was discharged from hospital on Tuesday night while the other was moved to another hospital for "specialist treatment".
The force said many people were in the area at the time and appealed for witnesses to come forward.
Det Insp Sion Margrie said: "It is likely someone saw or heard what happened, or even filmed the incident on their mobile phones."


Road racer Michael Dunlop has edged out short circuit star Jonathan Rea to win the Adelaide Enkalon Irish Motorcyclist of the Year award for the first time.

Dunlop became the first rider to win four races at the Isle of Man TT in successive years in 2014 and was a double winner at the North West 200.
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Dunlop was also named International Road Racer of the Year, with Rea chosen as Short Circuit Rider of the Year.
The late Tom Herron was posthumously inducted into the Hall of Fame.
Skerries rider Michael Sweeney won National Road Racer of the Year, while Alastair Seeley, winner of the main award in 2012, was Best Rider on UK and Ireland circuits.
Carrickfergus rider Seeley was second in the British Supersport Championship for Mar-Train Racing, winning eight races during the course of the season.
Andy Reid, who was just pipped to the British Superstock 600cc title, was Young Rider of the Year, Lee Johnston received a Special Recognition Award and John Burrows Racing was selected as Team of the Year.
William Dunlop collected the Race of the Year for his last lap duel with brother Michael in Saturday's opening Superbike event at the North West 200.
Bishopscourt race circuit owner Jim O'Brien won the Services to Motorcycling prize and Richard McNeill picked up an Outstanding Achievement Award for winning the Formula 600 British Championship.
Mark McLernon was announced as the Off Road Rider of the Year.
The judging panel could not be separated between Dunlop and Rea for the main award, the Joey Dunlop Trophy, so the accolade was eventually decided by the public online poll, which saw Michael receive 26.5% of the vote.


The government has pledged its "full and unfettered" support for a bill that would force councils in England to do more to tackle homelessness.

Bob Blackman MP said it was a "national disgrace" that a single person should have to sleep rough.
His private member's bill aims to reform the law to make sure more people get help before losing their home.
A former housing minister had warned that councils would need more funding to fulfil the commitment.
As-it-happened: Homelessness debate
The well-attended debate saw MPs from different parties broadly support the private member's bill.
It passed its first Parliamentary hurdle in the Commons on Friday when it was approved by MPs without any votes against it. The Homelessness Reduction Bill will now go forward for detailed scrutiny.
Communities and Local Government Minister Marcus Jones reiterated the government's "full and unfettered support" for the Homelessness Reduction Bill, adding that the government would fund the extra costs to councils arising from the changes it proposes.
Conservative MP Mr Blackman's bill amends the 1996 Housing Act to change the definition of being "threatened with homelessness", obliging councils to assess people at risk of homelessness at an earlier stage.
Currently the threat of homelessness is defined as beginning 28 days before a person is likely to become homeless.
The bill would extend that period to 56 days, giving people longer to seek help from their local authority.
It would also oblige councils to offer support in finding accommodation for people who become homeless for a further 56 days.
The categories of people eligible for council support would also be expanded, in a move away from the current focus on "priority housing lists" based on applicants' vulnerabilities.
Harrow East MP Mr Blackman called for a "culture change in councils", moving their priorities from "crisis management" to a pro-active approach in preventing homelessness.
He said he had looked at the experience of the Welsh Assembly, which introduced similar measures in 2015 and had since seen a 69% reduction in the number of households receiving homelessness duty.
For Labour, shadow housing secretary John Healey called for more government support for local authorities, saying: "If ministers mean what they say about homelessness, they must do two things: fund the costs of the extra duties in this bill in full, and tackle the causes of the homelessness crisis in this country."
Conservative former housing minister Mark Prisk said there "will be the need, when required, for additional funding for many councils in order for them to fulfil that commitment".
Labour's Stephen Pound said that in many cases local authorities were simply unable to house homeless people, saying that "councils don't lack empathy, they lack housing."
Chairman of the Local Government Association Lord Porter echoed concerns over a lack of housing, saying: "It is clear that legislative change alone will not resolve homelessness.
"If we are all to succeed, then all new duties proposed in the bill will need to be fully funded. Councils need powers to resume our role as a major builder of affordable homes."
Homelessness charity St Mungo's, which had encouraged MPs to support the bill, said it would "fill a gap in legislation that means many people get little or no support to avoid the dangers of sleeping rough".
The charity's Executive Director of Strategy and Policy Dominic Williamson said: "If the Homelessness Reduction Bill becomes law, it will be a major step towards ensuring help to prevent and tackle homelessness is available to everyone. "


The stakes could not be higher for China, the largest investor in South Sudan's oil sector, as fierce fighting continues between forces loyal to President Salva Kiir and those of his former deputy.

Some of the largest oil fields China operates are in areas controlled by fighters backing Riek Machar, the country's vice-president until he was sacked in July.
Oil production has already dropped by 20% since the onset of the conflict three weeks ago and more than 300 Chinese workers have been evacuated.
The spectre of their Libyan experience also weighs heavily on the Chinese minds - project after project now lies deserted because of heavy fighting during the Arab Spring uprising of 2011, inflicting huge losses on China.
It is no surprise then that China is putting its full weight behind the peace talks in Addis Ababa.
Foreign Minister Wang Yi was in the Ethiopian capital on Monday and made it clear that China wanted both sides to stop fighting and seek a reasonable and rational way out.
According to media reports, he was even willing to mediate personally between the warring sides.
It is unclear if Mr Wang has been able to do this, but his message was important, reports the BBC's Emmanuel Igunza from Addis Ababa.
It demonstrates how seriously the international community is taking the crisis - with many diplomats present at the talks, he says.
Apart from China's Africa envoy Zhong Jianhua, US special envoy Donald Booth and EU special representative Alexander Rondos are also attending.
China invested some $20bn (Â£12bn) in Sudan before it split into two countries in 2011, according to Chinese media reports.
Another $8bn was pledged to President Kiir during his visit to China the year following secession, to be used for infrastructure projects and the oil sector.
The heavy investment seems to have borne fruit, as in the first 10 months of 2013, China imported 1.9 million tonnes of oil (nearly 14 million barrels) from South Sudan, twice as much as China imports from Nigeria each year.
Though amounting to less than 1% of China's total oil imports, it makes up roughly two-thirds of oil exported by the world's youngest nation and is expected to increase.
Two years ago, China suffered heavy losses in its Libyan projects, including infrastructure, telecommunications and oil.
Many constructions were halted and sites looted or destroyed during the revolution which toppled long-time leader Muammar Gaddafi.
The total loss was estimated by several Chinese media reports to be in the region of $20bn, although no official figures exist.
Compensation talks with the new Libya government stalled as their priority was very much on nation-building and improving the living conditions of the Libyan people.
Experts point out that China has taken tremendous risks in its search for oil.
This is because the country's economic boom continues to require a great deal of oil - home production is limited and reliance on exports reached 56% in 2012.
But all the known global markets have been dominated by Western companies or have been off-limits because of sanctions, leaving China with little choice but to adopt high-risk strategies.
Nowadays, more than half of China's investment in the overseas oil sector is found in areas which are considered unstable, including Iran, Nigeria, Sudan, South Sudan and Venezuela.
Chinese workers have been caught in the conflicts for control of oil by various forces in Sudan.
In 2008, five Chinese oil workers kidnapped by rebels in Sudan's South Kordofan province were killed during a rescue attempt.
Four years later, another 29 Chinese construction workers were abducted in the same province and were only released 11 days later after intense negotiations.
The Sudanese rebels were quoted as saying that they did not want to harm the workers, but they aimed to send a signal to the Chinese government that they did not want them to be involved in the conflict over oil in Sudan.
But what is currently happening in South Sudan seems far more serious than kidnappings.
China must be praying for a quick end to the trouble so life on the oil fields can return to normal.
In the meantime, some experts also predict that China might be forced into re-thinking its high-risk oil strategy.


Plans to open a 32-mile stretch of the hard shoulder on the M4 motorway to traffic have been approved.

It will see the M4 between Hayes in west London and Theale in Berkshire widened to become a fourth lane with a variable speed limit.
Transport Secretary Chris Grayling said it was a "critical need" and would "improve traffic flow".
Environmental and transport groups said the loss of a hard shoulder would be hazardous and "bad news for motorists".
Giving the green light for the proposal to transform the motorway between junction three to 12, Mr Grayling said in a letter there was a "critical need to improve the existing national road network".
The move will "increase capacity, improve traffic flow and reduce journey times, thereby supporting economic development", he added.
Bridget Fox, sustainable transport campaigner, said: "This is bad news for both motorists and local residents.
"Motorists and breakdown operatives will be exposed to greater risk with the loss of the hard shoulder."
Dubbing the move as "expanding motorways on the cheap", she called for investment in the railway and other alternatives.
Jenny Bates, of Friends of the Earth, said: "Widening the M4 will lead to more traffic, more climate changing emissions and increase air pollution levels that already break legal health limits."
In June, a report published by the Transport Select Committee warned ministers against plans to convert hard shoulders into permanent driving lanes citing serious concerns over "all-lane running" schemes.
The scheme is already in operation in sections of the M25, M1 and M6 and plans for the scheme to be used in parts of other motorways - including the M3 and M23 - are in place.


YouTube has warned it will clamp down on users who buy 'fake views' to make their videos look more popular than they really are.

With 100 hours of video added to the site every minutes it can be hard to get noticed, so some people buy fake views.
There are many companies that will sell YouTube views, likes or comments for a fee.
Most videos have genuine views but the website wants to crack down on the small number that don't.