Acrylamide in Foods
Acrylamide is a chemical compound that occurs as a solid crystal or in liquid solution. Its primary use is to make polyacrylamide and acrylamide copolymers. Trace amounts of the original (unreacted) acrylamide generally remain in these products. Polyacrylamide and acrylamide copolymers are used in many industrial processes, including production of paper, dyes, and plastics, and the treatment of drinking water, sewage and waste. They are also present in consumer products such as caulking, food packaging and some adhesives.
Historically, exposure to high levels of acrylamide in the workplace has been shown to cause neurological damage.
Acrylamide has not been shown to cause cancer in humans. However, the relationship between acrylamide and cancer has not been studied extensively in humans. Because it has been shown to cause cancer in laboratory rats when given in the animals' drinking water, both the Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC) in Lyon, France, consider acrylamide to be a probable human carcinogen. The National Toxicology Program's Ninth Report on Carcinogens states that acrylamide can be "reasonably anticipated to be a human carcinogen."
Recent studies by research groups in Sweden, Switzerland, Norway, Britain and the United States have found acrylamide in certain foods. It has been determined that heating some foods to a temperature of 120 C (248 F) can produce acrylamide. Potato chips and french fries have been found to contain relatively high levels of acrylamide compared to other foods, with lower levels also present in bread and cereals. A joint World Health Organization and Food and Agriculture Organization (WHO/FAO) consultation in June 2002 concluded that the levels of acrylamide in foods pose a major concern and called for more research to determine what the risk is and what should be done.
In September 2002, researchers discovered that the amino acid asparagine, which is present in many vegetables, with higher amounts in some varieties of potatoes, can form acrylamide when heated to high temperatures in the presence of certain sugars. High-heat cooking methods, such as frying, baking or broiling, are most likely to result in acrylamide formation. Boiling and microwaving appear less likely to form acrylamide. Longer cooking times increase the amount of acrylamide produced when the temperature is high enough.
There are other ways humans are exposed to acrylamide, but exposure through food is one of the largest sources. Cigarette smoke may be a major source for some people. Exposure to acrylamide from other sources is likely to be significantly less than that from food or smoking, although scientists do not yet have a complete understanding of all the sources. There are some industrial and agricultural uses of acrylamide and polyacrylamide. However, regulations are in place to limit exposure in those settings.
The EPA regulates acrylamide and has established acceptable levels for air and drinking water, at which exposure is considered to have no effect. These levels are set low enough to counteract any uncertainty arising from the lack of human data on the relationship between acrylamide and cancer. FDA regulates the amount of residual acrylamide in a variety of materials that come in contact with food. There are currently no guidelines governing the presence of acrylamide in food itself.
In setting its level for acrylamide in drinking water, EPA assumes people drink two liters, approximately four and a half pounds, of water a day. Since people do not eat four and a half pounds a day of foods like french fries or potato chips, a direct comparison of drinking water to these products without considering absolute food intake is inappropriate Scientists also do not know whether the absorption in the gut of acrylamide from food is similar to that from water. The simplest way to think about this is that the levels in food are, as the World Health Organization put it, a major concern. However, scientists still do not know whether the acrylamide that has been in food for thousands of years has any effect on health.
The best advice at this early stage in our understanding of this complex issue is to follow established dietary guidelines and eat a healthy, balanced diet that is low in fat and rich in high-fiber grains, fruits, and vegetables.
The WHO/FAO consultation concluded that further research is necessary to determine how acrylamide is formed during the cooking process and whether acrylamide is present in foods other than those already tested. They also recommended population-based studies of those cancers that could potentially develop due to exposure to acrylamide.
Last Editorial Review: 7/8/2005