BIG oil companies, lead by BP, Total and Shell, have polluted the North Sea with 69 oil and chemical spillages over the last three months, the Sunday Herald can reveal.

As many as 18 companies from across the world have been named and shamed by the UK Government for a catalogue of blunders on offshore oil and gas rigs, including numerous equipment failures, pipe leaks, breaks and flaws.

The revelations have shocked and angered environmentalists who attack the oil and gas industry for "conning" the public about safety. Companies are putting workers, wildlife and ultimately the world at risk, they say.

Professor Andrew Watterson, head of the Occupational and Environmental Health Research Group at the University of Stirling, accused companies of playing down "the potentially catastrophic consequences" of gas and oil leaks.

"These are very worrying figures that cannot be slicked over by Government agencies and industry," he said. He blamed "corporate failures" for polluting the sea, and pointed out that the number of reported chemical leaks had more than doubled since 2005.

The Department of Energy and Climate Change (DECC) has released details of all spillages of oil and related chemicals in the North Sea since the beginning of 2012, and from now on will publish these details on a monthly basis rather than annually. This follows controversy over the implications of the continuing gas leak from the Elgin rig, run by the French company, Total, 140 miles east of Aberdeen.

British oil giant, BP, comes out as the company guilty of by far the most pollution lapses, with 23 of the 69 spills occurring at its rigs. Total was the second worst with seven spills, closely followed by another British company, Shell, with six spills.

Other companies implicated included British Gas, the UK firms EnQuest and Perenco, and the Canadian companies Nexen and Talisman. There were also spills at platforms run by Denmark's Maersk, the US's ChevronTexaco and Abu Dhabi's Taqa Bratani (see tables on page 10).

Just over half of the spills, 37, were chemicals, while the rest were different types of oil. The leaks included crude oil, diesel, condensate, glycol, methanol and other chemicals used in the drilling process.

Among the mishaps listed by DECC were "subsea hose failure", "faulty connection", "weld failure", "control line failure" and "hose defect". The last entries on the list are the latest leaks from Total's Elgin platform on March 25, which are said to be "under review".

The list discloses that Total suffered an earlier leak on the same platform on January 10. Oil spilled after a safety valve on a hydraulic oil accumulator wrongly opened.

The company also had chemical spills at its Sedco, Dunbar, Rowan Gorilla and Alwyn North rigs. Separate information from the Government's Health and Safety Executive (HSE) shows that Total was served two legal improvement notices last year because of safety lapses on the Alwyn North rig.

In August, the company was accused by the HSE of failing to properly assess the risks of moving heavy loads that "led to an accident occurring causing a serious injury". And last May it failed "to adequately control exposure of persons to substances hazardous to health", HSE said.

Dr Richard Dixon, the director of WWF Scotland, thought people would be shocked to learn there had been so many mishaps in such a short space of time. "The companies involved should be ashamed of this catalogue of faulty valves, operator mistakes and broken hoses," he said.

Oil & Gas UK, which represents offshore companies, defended the industry's record by arguing that many of the leaks were "relatively small and unlikely to impact on the marine environment". Many of the chemicals accidentally spilled were "benign", it said.

THE Government's figures show that 1.7 tonnes of chemicals and 600 kilograms of oil have been spilled in the last three months, though in many cases figures are not given because the leaks are still "under review". More than 4600 tonnes of chemicals and 300 tonnes of oil have been spilled in the North Sea since 2005.

Mick Borwell from Oil & Gas UK said that companies tried hard to avoid spills. "The industry takes its obligations to the environment very seriously and is committed to continuing to work with the Government and environmental agencies to minimise the environmental footprint of operations," he said.

BP pointed out that all releases, no matter how small, were reported to the Government. "The industry continues to make every effort to improve its environmental performance, including the elimination of even the smallest releases," said a company spokesman.

Total said that three of its previous leaks were less than 100 litres, though one was six tonnes. "We take all possible measures to prevent spills and, as we hope our current actions on the Elgin gas leak demonstrate, we try to respond quickly and effectively should they occur," said a company spokesman.

Shell argued that lessons were learned from every spillage. "No spill is acceptable and we are working hard to stop spills wherever they may happen," said a Shell spokeswoman.

Greenpeace, however, maintained that oil companies were misleading the public over their safety record. "These figures show the scale of the confidence trick they have perpetrated," said the environmental group's energy campaigner, Vicky Wyatt.

"Nearly every day there's a serious incident on either a gas or oil platform. So far we have been lucky and avoided a major disaster. But the luck of companies like BP and Shell can't go on forever and when their luck does run out it will be the people of Scotland and the natural habitat that will pay the price."