Acrylamide in Food and Cancer Risk
Key Points
- Acrylamide is a chemical used primarily for industrial purposes (see
Question 1).
- Acrylamide has been found in certain foods, with especially high
levels in potato chips, French fries, and other food products produced
by high-temperature cooking (see Question 2).
- Food and cigarette smoke are the major sources of exposure to acrylamide
(see Question 6).
- Acrylamide is considered to be a mutagen and a probable human carcinogen,
based mainly on studies in laboratory animals (see Question
7).
- Scientists do not yet know with any certainty whether the levels of acrylamide typically found in some foods pose a health risk for humans (see Questions
7 and 10).
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- What is acrylamide?
Acrylamide is a chemical used primarily as a building block in making polyacrylamide
and acrylamide copolymers. Polyacrylamide and acrylamide copolymers are used
in many industrial processes, such as the production of paper, dyes, and plastics,
and in the treatment of drinking water and wastewater, including sewage. They
are also found in consumer products, such as caulking, food packaging, and
some adhesives. Trace amounts of acrylamide generally remain in these products.
- Is there acrylamide in food?
Researchers in Europe and the United States have found acrylamide in certain
foods that were heated to a temperature above 120 degrees Celsius (248 degrees
Fahrenheit), but not in foods prepared below this temperature (1).
Potato chips and French fries were found to contain higher levels of acrylamide
compared with other foods (2). The World Health Organization
(WHO) and the Food and Agriculture Organization (FAO) stated that the levels
of acrylamide in foods pose a “major concern” and that more research
is needed to determine the risk of dietary acrylamide exposure (2).
- How does cooking produce acrylamide?
Asparagine is an amino acid (a building block of proteins) that is found
in many vegetables, with higher concentrations in some varieties of potatoes.
When heated to high temperatures in the presence of certain sugars, asparagine
can form acrylamide. High-temperature cooking methods, such as frying, baking,
or broiling, have been found to produce acrylamide (3),
while boiling and microwaving appear less likely to do so. Longer cooking
times can also increase acrylamide production when the cooking temperature
is above 120 degrees Celsius (4, 5).
- Is there anything in the cooking process that can be
changed to lower dietary acrylamide exposure?
Decreasing cooking time, blanching potatoes before frying, and postdrying
(drying in a hot air oven after frying) have been shown to decrease the acrylamide
content of some foods (6, 7).
- Should I change my diet?
Acrylamide levels in food vary widely depending on the manufacturer, the
cooking time, and the method and temperature of the cooking process (8,
9). The best advice at this time 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.
- Are there other ways humans are exposed to acrylamide?
Food and cigarette smoke are the major sources of acrylamide exposure (10).
Exposure to acrylamide from other sources is likely to be significantly less
than that from food or smoking, but scientists do not yet have a complete
understanding of all sources of exposure. Acrylamide and polyacrylamide are
used in some industrial and agricultural procedures, and regulations are in
place to limit exposure in those settings.
- Does acrylamide increase the risk of cancer?
Studies in rodent models have found that acrylamide exposure poses a risk
for several types of cancer (11, 12,
13). However, the evidence from human studies is still
incomplete. The National Toxicology Program (NTP) and the International Agency
for Research on Cancer consider acrylamide to be a “probable human carcinogen,”
based on studies in laboratory animals given acrylamide in drinking water.
However, toxicology studies have shown differences in acrylamide absorption
rates between humans and rodents (14).
A series of case-control studies have investigated the relationship between
dietary intake of acrylamide and the risk of developing cancers of the
oral cavity, pharynx, esophagus, larynx, large bowel, kidney, breast, and ovary.
These studies generally found no excess of tumors associated with acrylamide
intake (15, 16, 17,
18, 19). In the studies, however, not
all acrylamide-containing foods were included in estimating exposures. In
addition, information in case-control studies about exposures is often based
on interviews (personal or through questionnaires) with the case and control
subjects, and these groups may differ in the accuracy of their recall about
exposures. One factor that might influence recall accuracy in cancer-related
dietary studies is that diets are often altered after receiving a diagnosis
of cancer.
To avoid such limitations in accurately determining acrylamide exposure,
biomarkers of exposure were recently used in a Danish cohort study designed
to evaluate the subsequent risk of breast cancer in postmenopausal women (20).
Among women with higher levels of acrylamide bound to the hemoglobin in their
blood, there was a statistically significant increase in risk of estrogen receptor-positive breast cancer. This finding suggests an endocrine hormone-related
effect, which would be consistent with the results of a questionnaire-based
cohort study in the Netherlands that found an excess of endometrial and ovarian cancer—but not of postmenopausal breast cancer—associated with higher levels
of acrylamide exposure (21). Another cohort study from
the Netherlands suggested a positive association between dietary acrylamide
and the risk of renal cell cancer, but not of prostate or bladder cancer (22).
- What are other health effects of acrylamide?
High levels of acrylamide in the workplace have been shown to cause neurological
damage, e.g., among workers using acrylamide polymers to clarify water in
coal preparation plants (23).
- Are acrylamide levels regulated?
The U.S. Environmental Protection Agency (EPA) regulates acrylamide in drinking
water. The EPA established an acceptable level of acrylamide exposure, set
low enough to account for any uncertainty in the data relating acrylamide
to cancer and neurotoxic effects. The U.S. Food and Drug Administration regulates
the amount of residual acrylamide in a variety of materials that come in contact
with food, but there are currently no guidelines governing the presence of
acrylamide in food itself.
- What research is needed?
Although studies in rodent models suggest that acrylamide is a potential
carcinogen, additional epidemiological cohort studies are needed to help determine
any effects of dietary acrylamide intake on human cancer risk. It is also
important to determine how acrylamide is formed during the cooking process
and whether acrylamide is present in foods other than those already tested.
This information will enable more accurate and comprehensive estimates of
dietary exposure. Biospecimen collections in cohort studies will provide an
opportunity to avoid the limitations of interview-based dietary assessments
by examining biomarkers of exposure to acrylamide and its metabolites in relation
to the subsequent risk of cancer.
For information about acrylamide in food from the WHO and FAO, please visit
the WHO Web site at http://www.who.int/foodsafety/chem/chemicals/acrylamide/en
on the Internet.
For information about acrylamide from the NTP’s Eleventh Report on
Carcinogens, please visit http://ntp.niehs.nih.gov/index.cfm?objectid=32BA9724-F1F6-975E-7FCE50709CB4C932
on the Internet.
Selected References
- Stadler RH, Blank I, Varga N, et al. Acrylamide from
Maillard reaction products. Nature 2002; 419(6906):449–450.
- Food and Agriculture Organization of the United Nations. World Health Organization. Summary report of the sixty-fourth meeting
of the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Retrieved
July 24, 2008, from: http://www.who.int/entity/ipcs/food/jecfa/summaries/summary_report_64_final.pdf.
- Mottram DS, Wedzicha BL, Dodson AT. Acrylamide is formed
in the Maillard reaction. Nature 2002; 419(6906):448–449.
- Gertz C, Klostermann S. Analysis of acrylamide and
mechanisms of its formation in deep-fried products. European Journal of
Lipid Science and Technology 2002; 104(11):762–771.
- Rydberg P, Eriksson S, Tareke E, et al. Investigations
of factors that influence the acrylamide content of heated foodstuffs. Journal
of Agricultural and Food Chemistry 2003; 51(24):7012–7018.
- Kita A, Brathen E, Knutsen SH, Wicklund T. Effective
ways of decreasing acrylamide content in potato crisps during processing.
Journal of Agricultural and Food Chemistry 2004; 52(23):7011–7016.
- Skog K, Viklund G, Olsson K, Sjoholm I. Acrylamide
in home-prepared roasted potatoes. Molecular Nutrition and Food Research
2008; 52(3):307–312.
- Tareke E, Rydberg P, Karlsson P, Eriksson S, Tornqvist
M. Analysis of acrylamide, a carcinogen formed in heated foodstuffs. Journal
of Agricultural and Food Chemistry 2002; 50(17):4998–5006.
- Mojska H, Gielecinska I, Szponar L. Acrylamide content
in heat-treated carbohydrate-rich foods in Poland. Roczniki Panstwowego
Zakladu Higieny 2007; 58(1):345–349.
- Urban M, Kavvadias D, Riedel K, Scherer G, Tricker
AR. Urinary mercapturic acids and a hemoglobin adduct for the dosimetry of
acrylamide exposure in smokers and nonsmokers. Inhalation Toxicology
2006; 18(10):831–839.
- Dearfield KL, Abernathy CO, Ottley MS, Brantner JH,
Hayes PF. Acrylamide: Its metabolism, developmental and reproductive effects,
genotoxicity, and carcinogenicity. Mutation Research 1988; 195(1):45–77.
- Dearfield KL, Douglas GR, Ehling UH, et al. Acrylamide:
A review of its genotoxicity and an assessment of heritable genetic risk.
Mutation Research 1995; 330(1–2):71–99.
- Friedman M. Chemistry, biochemistry, and safety of
acrylamide. A review. Journal of Agricultural and Food Chemistry
2003; 51(16):4504–4526.
- Fuhr U, Boettcher MI, Kinzig-Schippers M, et al.
Toxicokinetics of acrylamide in humans after ingestion of a defined dose in
a test meal to improve risk assessment for acrylamide carcinogenicity. Cancer
Epidemiology Biomarkers and Prevention 2006; 15(2):266–271.
- Pelucchi C, Galeone C, Levi F, et al. Dietary acrylamide
and human cancer. International Journal of Cancer 2006; 118(2):467–471.
- Mucci LA, Dickman PW, Steineck G, Adami HO, Augustsson
K. Dietary acrylamide and cancer of the large bowel, kidney, and bladder:
Absence of an association in a population-based study in Sweden. British
Journal of Cancer 2003; 88(1):84–89.
- Mucci LA, Lindblad P, Steineck G, Adami HO. Dietary
acrylamide and risk of renal cell cancer. International Journal of Cancer
2004; 109(5):774–776.
- Mucci LA, Adami HO, Wolk A. Prospective study of
dietary acrylamide and risk of colorectal cancer among women. International
Journal of Cancer 2006; 118(1):169–173.
- Mucci LA, Sandin S, Balter K, et al. Acrylamide intake
and breast cancer risk in Swedish women. Journal of the American Medical
Association 2005; 293(11):1326–1327.
- Olesen PT, Olsen A, Frandsen H, et al. Acrylamide
exposure and incidence of breast cancer among postmenopausal women in the
Danish Diet, Cancer and Health Study. International Journal of Cancer
2008; 122(9):2094–2100.
- Hogervorst JG, Schouten LJ, Konings EJ, Goldbohm
RA, van den Brandt PA. A prospective study of dietary acrylamide intake and
the risk of endometrial, ovarian, and breast cancer. Cancer Epidemiology
Biomarkers and Prevention 2007; 16(11):2304–2313.
- Hogervorst JG, Schouten LJ, Konings EJ, Goldbohm
RA, van den Brandt PA. Dietary acrylamide intake and the risk of renal cell,
bladder, and prostate cancer. American Journal of Clinical Nutrition
2008; 87(5):1428–1438.
- Mulloy KB. Two case reports of neurological disease
in coal mine preparation plant workers. American Journal of Industrial
Medicine 1996; 30(1):56–61.
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