CONSUMERS were left wondering if anything was safe to eat yesterday after researchers discovered that cooking most foods produced possible cancer-causing chemicals.

Scientists working for the UK Food Standards Agency have confirmed a chance discovery in Sweden last month that ''significant'' levels of acrylamide occur in a wide range of cooked and processed food.

Findings from both countries were presented in Brussels yesterday to the Scientific Committee on Food which advises the European Commission on food safety.

World Health Organisation experts will also discuss the research at a meeting in Geneva next month. They are expected to recommend further studies to obtain a clearer picture of the risks.

Scientists say they do not know precisely how acrylamide gets into food or what the dangers are for human health, and said they were not advising people to switch their diet or cooking methods.

Rats given doses a thousand times higher than the human consumption levels detected in Sweden developed tumours in a wide range of tissues. But no-one knows how small a dose of the chemical may be harmful.

The British study focused on potatoes, crisps, breakfast cereals, and rye crispbreads, but experts say other foods, including meat, may be at risk.

According to the findings, acrylamide forms naturally in foods when they are fried or baked. However, scientists believe it also occurs in roasted, grilled, and barbecued food.

The discovery that food contains acrylamide was made by chance as a result of a Swedish study of tunnel workers, who use it in the formation of waterproof linings.

The workers were found to have abnormal levels of acrylamide in their bodies, but so too did the control volunteers with whom they were compared. This sparked off an investigation by the Swedish National Food Authority into their diet.

Measuring probable daily intake, the Swedes concluded that people might be consuming up to 100 micrograms of acrylamide per day, more than 1000 times lower than the doses found to have cancerous or neurotoxic affects in animals.

Existing European rules allow no more than 10 parts per billion in packaging.

The FSA study used two different types of test and found 310 and 350 parts per billion of acrylamide in Sainsbury's potatoes, after they were chipped and fried. Raw, the level was less than 10 parts per billion.

Other findings include: Ross chips 12,000-12,800 ppb; Walkers crisps 1220 to 1280 ppb; Pringles crisps 1480 ppb; Kellogg's Special K, 300 ppb; Kellogg's Rice Krispies 110-150 ppb; Ryvita 1340-4000 ppb.

Dr Andrew Wadge, head of chemical safety and toxicology at the FSA, said: ''It is likely that any risks from acrylamide are not new and we have probably been exposed to them in food for generations.

''We are not recommending that people change either their diet or cooking methods as a result of these studies. We are recommending that people should eat a balanced diet and a wide variety of fruit and vegetables.''

Hugh Pennington, professor of microbiology at Aberdeen University and a leading food safety expert, said: ''These chemicals have been around for a long time. My guess is that there will be no risk''.

Acrylamide is highly reactive, which means that it is capable of damaging DNA, inducing genetic mutation, and chromosonal damage.

The new research and another study into acrylamide's effect on workers at three US plants with high exposure levels have both so far proved inconclusive on whether the chemical increases the risk of cancer.

There was an increase of deaths from pancreatic cancer in the studies, but not on a scale considered significant.

Before the discovery of acrylamide's presence in food, exposure to the chemical was believed to primarily be of danger to workers in the paper and pulp, construction, oil drilling, textiles, mining, or plastics industries, or to the general public through contaminated water.