The Consultation of 23 scientific experts, specializing in carcinogenicity, toxicology, food technology, biochemistry and analytical chemistry, identified a number of important issues for which research is urgently needed. While acrylamide is known to cause cancer in laboratory animals, no studies of the relationship between acrylamide and cancer in humans have been done.
The theoretical models to predict whether cancer would develop in humans from current average intake levels are not reliable enough to develop firm conclusions. When investigated in rats, acrylamide has a potency similar to certain other well-known carcinogens formed through cooking, such as certain aromatic hydrocarbons formed in meat when fried or grilled. However the intake levels for acrylamide are likely to be higher. Therefore, the consultation recognized that the issue of acrylamide in food is a major concern.
The Consultation did not consider the data available to be adequate to present specific quantitative estimates of cancer risk posed by levels of acrylamide in people's diets. The scientists urged investigation of the possibilities for reducing the levels of acrylamide in food by changes in formulation, processing and other practices.
Acrylamide is a chemical used in the manufacture of plastics. It was first discovered to be present in certain foods cooked at high temperatures as the result of work announced in Sweden in April 2002. It is a known carcinogen and causes nerve damage.
The Swedish research, and subsequent studies in Norway, Switzerland, the United Kingdom and the United States, have found that acrylamide levels in certain starch-based foods, such as potato chips, french fries, cookies, cereals and bread, were well above the level given in the World Health Organization's Guideline Values for Drinking Water Quality.
Yet the average intake levels of acrylamide from all sources were determined to be in the range of 70 micrograms per day for an adult, i.e., a range significantly below that which is known to cause nerve damage in laboratory animals.
"After reviewing all the available data, we have concluded that the new findings constitute a serious problem. But our current limited knowledge does not allow us to answer all the questions which have been asked by consumers, regulators and other interested parties," said Dr Dieter Arnold, Chairman of the United Nations Food and Agriculture Organization/World Health Organization hosted meeting in Geneva.
Foods in which acrylamide develops when cooked at above 120 degrees Celsius include potato chips, french fries, bread and processed cereals. However, the scientists noted, they were not able to determine if other foods also contained acrylamide, as the research has not yet been conducted. The experts emphasized that data on foods consumed as parts of diets in regions other than Europe and North America is missing and more research is needed here.
Consequently, it is not yet possible to determine what percentage of overall acrylamide presence in the human body comes from starch-based foods. Indeed, because other food, such as fruits, vegetables, meats and seafood, and beverages and other exposures such as cigarettes, can also result in acrylamide entering the human body, it is not known what percentage of the total acrylamide in a human body is from food sources.
And scientists do not yet know how quickly the body can break down acrylamide.
The Consultation recommended that more research is necessary in areas including: