Could this kill you?

Following the announcement on April 24 by the Swedish National Food Administration (NFA) that acrylamide, a known carcinogen in animal tests, has been found in elevated levels in starch-containing foods cooked at high temperatures, such as potato products and bread, the World Health Organization (WHO) is to organise an expert consultation to determine the full extent of the public health risk from acrylamide in food.

Previous concerns about acrylamide were a result of known human exposure through drinking water and through certain specialised occupations. The Swedish announcement was the first report of the presence of elevated levels of acrylamide in food.

WHO officials have stressed that, although many pieces of information about acrylamide and its effects in animals do exist, a full picture of the levels in food and effects on humans does not, and therefore WHO will be looking to fill in relevant gaps in knowledge.

In 1994, the International Agency for Research on Cancer of WHO evaluated acrylamide as 'probably carcinogenic to humans.'

This evaluation was based on sufficient evidence of carcinogenicity in experimental animals and extensive supplementary evidence that acrylamide has a chemically reactive mode of action as a toxicant. The few epidemiologic studies of acrylamide that were available at that time were inadequate to establish that occupational exposures to acrylamide had increased cancer risks in exposed workers.

In announcing the discovery of high levels of acrylamide in food by research teams at Stockholm University and the Swedish National Food Administration (NFA), the NFA said that: 'Present knowledge does not allow for a balanced analysis of risks and benefits of staple foods containing acrylamide. The Swedish NFA can currently only issue general advice regarding the risk management of acrylamide to the food industry and consumers. More knowledge is needed before the dietary advice issued by the NFA can be changed.'

In the Swedish studies, the level of acrylamide produced during food preparation was reported to increase with the temperature at which the food is cooked.

WHO emphasised that several questions still need to be resolved before more definitive advice can be given. For example, is acrylamide taken up from food as readily as it is from water? If it is, what is the risk that this uptake will lead to harmful effects in humans?

The WHO informal expert consultation, planned to take place before the end of June, will look at these questions. Other topics that the consultation will consider are epidemiological data, levels in food in other countries, processing conditions that either increase or reduce those levels, and development of appropriate guidance to reduce exposure to acrylamide.

Upon hearing the news, the UK Food Standards Agency (FSA) issued the advice that consumers did not need to change their diet.

In a statement, the FSA said: 'Acrylamide has never before been found at these levels in foods, but we do take this work seriously and will investigate the issue further. In the meantime, there is no need for people to change their diets.'

The American Council on Science and Health (ACSH) also seemed wary of the news.

'There is no compelling evidence which supports the claim by Swedish researchers that fried or baked foods high in starch introduces chemicals which increase the risk of human cancer,' it said in a statement.

'We are deeply concerned that Americans will unnecessarily worry about safe, nutritious foods after hearing today's news,' added Dr. Elizabeth M. Whelan, the President of ACSH.

'The claim that acrylamide, found in common foods such as potatoes and bread, after cooking, poses a human cancer risk is based exclusively on high dose studies in laboratory animals. There is no evidence whatever that humans who eat the observed levels of acrylamide are exposed to any risk of any type of cancer,' noted Dr. Whelan.

'Food is a highly emotional subject,' said Dr. Whelan, 'and the news reports resulting from the alarmist study only proves that a rumour about food safety can be half way around the world before the truth gets its boots on.'

'It's just dumb, dumb, dumb,' said Stephen Safe, a professor of toxicology at Texas A&M.

'There are carcinogens in everything you eat. Maybe they'll just ban food,' he said in an interview in last week's New York Times.

Editor's note: Acrylamide is a chemical intermediate used in the production and synthesis of polyacrylamides. These high-molecular weight polymers can be modified to develop nonionic, anionic, or cationic properties for specific uses. The principle end use of acrylamide is in water-soluble polymers used as additives for water treatment, enhanced oil recovery, flocculants, papermaking aids, thickeners, soil conditioning agents, sewage and waste treatment, ore processing, and permanent-press fabrics. Acrylamide is also used in the synthesis of dyes, in copolymers for contact lenses, and the construction of dam foundations, tunnels, and sewers.