Acrylamide

Acrylamide is an industrial chemical and used, together with polyacrylamide, for the production of plastics.  In 2002 a scientific group at the University of Stockholm found that acrylamide is formed during heating of starch-rich foods at high temperatures.

At The Swedish Food Agency a new and rapid LC/MS/MS-method was developed for the analysis of acrylamide in foods. Analyses have been performed at a regular basis in different food groups since the discovery and has shown that acrylamide is present in a large number of foods, and that the levels have been relatively constant over time.

Contribution from different food groups

The levels differ widely, both within and between food groups, with the highest levels found in fried and roasted potatoes, in crisps and in coffee. In Sweden, the intake is about 30-40 microgram acrylamide per person per day for adults.

• Coffe contributes to the exposure with 10-20 percent.
• Bread and cookies contribute with about 20-30 percent.
• Fries and crisps contribute with hardly 10 percent each.

Acrylamide is formed in cigarette smoke and may thus be an additional source of exposure for smokers. Acrylamide is water soluble and is quickly absorbed in the digestive tract. The excreation via the urine is fast and half of the acrylamide is cleared from the body in a few hours.

Toxicological effects

Effects in laboratory animals

The toxicological effects of acrylamide are well known. Neurological and reproductive effects have been observed in laboratory animals at high doses. In a study, where rats were given acrylamide in their drinking water, the lowest effective dose for neurological damage was 2 mg/kg body weight and day, and the highest no-effect dose was 0.5 mg/kg body weight and day.

Decreased fertility was observed in rats exposed to 5-10 mg acrylamide/kg body weight and day, which is a dose level that is several thousand times higher than the average intake from food. 

Effects on humans

Also humans exposed to high doses of acrylamide have shown neurological damage, for example some workers occupied in the building of the tunnel at Hallandsåsen at the end of the 1990s. The highest acrylamide dose that does not cause a neurological effect in humans is not known, but is likely much higher than the average acrylamide intake from food (ca 0.5 µg/kg body weight/day).

DNA damage

Acrylamide also causes DNA damage. It has been shown to induce gene mutations in cultured animal cells and also in treated animals. Thus it is assumed that exposure also to very low doses of acrylamide increases the risk for mutation and cancer. Studies on acrylamide, performed earlier at the Swedish Food Agency, have shown that chromosome aberrations are induced in mice at relatively low doses, and the linearity in the dose response curve points to an elevatad risk also at the very lowest doses testad.

Glycidamide, the metabolite of acrylamide that is considered to be resposible for the increase of the cancer risk, binds to DNA and can cause genetic damage. Prolonged exposure has induced tumours in rats, but cancer in man has not been convincingly shown.

Glycidamide has been found in mice and in rats, and also in humans exposed to acrylamide. The International Agency for Research on Cancer (IARC) has classified acrylamide as a "probably carcinogenic to humans" (Group 2A).