Acrylamide is a chemical used mainly in certain industrial processes, such as in making paper, dyes, and plastics, and in treating drinking water and wastewater. There are small amounts in some consumer products, such as caulk, food packaging, and some adhesives. Acrylamide is also found in cigarette smoke.
Acrylamide can also form in some starchy foods during high-temperature cooking, such as frying, roasting, and baking. Acrylamide forms from sugars and an amino acid that are naturally in food; it does not come from food packaging or the environment.
How are people exposed to acrylamide?
In certain foods
Acrylamide has probably always been in some foods, but this wasn’t known until Swedish scientists first found it in certain foods in 2002.
Acrylamide doesn’t appear to be in raw foods themselves. It’s formed when certain starchy foods are cooked at high temperatures (above about 250° F). Cooking at high temperatures causes a chemical reaction between certain sugars and an amino acid (asparagine) in the food, which forms acrylamide. Cooking methods such as frying, baking, broiling, or roasting are more likely to create acrylamide, while boiling, steaming, and microwaving appear less likely to do so. Longer cooking times and cooking at higher temperatures can increase the amount of acrylamide in foods further.
Acrylamide is found mainly in plant foods, such as potato products, grain products, or coffee. Foods such as French fries and potato chips seem to have the highest levels of acrylamide, but it’s also found in breads and other grain products. Acrylamide does not form (or forms at lower levels) in dairy, meat, and fish products.
In cigarette smoke
Acrylamide is also found in cigarette smoke. This is probably one of the major ways smokers are exposed.
On the job
People who work in certain industries (particularly in the paper and pulp, construction, foundry, oil drilling, textiles, cosmetics, food processing, plastics, mining, and agricultural industries) may be exposed to acrylamide in the workplace, mainly through skin contact or by breathing it in. Regulations limit exposure in these settings.
Does acrylamide increase the risk of cancer?
Researchers use 2 main types of studies to try to figure out if a substance causes cancer.
- Lab studies: In these studies, animals are exposed to a substance (often in very large doses) to see if it causes tumors or other health problems. Researchers might also expose normal cells in a lab dish to the substance to see if it causes the types of changes that are seen in cancer cells. It’s not always clear if the results from these types of studies will apply to humans, but lab studies are a good way to find out if a substance might possibly cause cancer.
- Studies in people: This type of study looks at cancer rates in different groups of people. It might compare the cancer rate in a group exposed to a substance to the cancer rate in a group not exposed to it, or compare it to the cancer rate in the general population. But sometimes it can be hard to know what the results of these studies mean, because many other factors might affect the results.
In most cases neither type of study provides enough evidence on its own, so researchers usually look at both lab-based and human studies when trying to figure out if something causes cancer.
Based on the studies done so far, it’s not yet clear if acrylamide affects cancer risk in people.
Studies in the lab
Acrylamide has been found to increase the risk of several types of cancer when given to lab animals (rats and mice) in their drinking water. The doses of acrylamide given in these studies have been as much as 1,000 to 10,000 times higher than the levels people might be exposed to in foods. It’s not clear if these results would apply to people as well, but in general it makes sense to limit human exposure to substances that cause cancer in animals.
Studies in people
Since acrylamide was first found in certain foods in 2002, dozens of studies have looked at whether people who eat more of these foods might be at higher risk for certain cancers.
Most of the studies done so far have not found an increased risk of cancer in humans. For some types of cancer, such as kidney, endometrial, and ovarian cancer, the results have been mixed, but there are currently no cancer types for which there is clearly an increased risk related to acrylamide intake.
The studies that have been done so far have had some important limits. For example, many of the studies relied on food questionnaires that people filled out every couple of years. These questionnaires might not have accounted for all dietary sources of acrylamide. In addition, people might not accurately remember what they have eaten when asked in personal interviews or through questionnaires.
While the evidence from human studies so far is somewhat reassuring, more studies are needed to determine if acrylamide raises cancer risk in people. The American Cancer Society supports the call by federal and international agencies for continued evaluation of how acrylamide is formed, its health risks, and how its presence in food can be reduced or removed.
What expert agencies say
Several national and international agencies study substances in the environment to determine if they can cause cancer. (A substance that causes cancer or helps cancer grow is called a carcinogen.) The American Cancer Society looks to these organizations to evaluate the risks based on evidence from laboratory, animal, and human research studies.
The International Agency for Research on Cancer (IARC) is part of the World Health Organization (WHO). Its major goal is to identify causes of cancer.
IARC classifies acrylamide as a “probable human carcinogen” based on data showing it can increase the risk of some types of cancer in lab animals. The evidence in humans was considered to be “inadequate” at the time of the last IARC review of the subject (1994), and at that time acrylamide was not known to be found in foods.
The National Toxicology Program (NTP) is formed from parts of several different US government agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA). In its most recent Report on Carcinogens (2014), the NTP has classified acrylamide as “reasonably anticipated to be a human carcinogen” based on the studies in lab animals.
The US Environmental Protection Agency (EPA) maintains the Integrated Risk Information System (IRIS), an electronic database that contains information on human health effects from exposure to various substances in the environment. The EPA classifies acrylamide as “likely to be carcinogenic to humans” based on studies in lab animals.
(For more information on the classification systems used by these agencies, see Known and Probable Human Carcinogens.)
It’s important to note that the determinations above are based mainly on studies in lab animals, and not on studies of people’s exposure to acrylamide from foods. Since the discovery of acrylamide in foods, the American Cancer Society, the FDA, and many other organizations have recognized the need for further research on this topic. Ongoing studies will continue to provide new information on whether acrylamide levels in foods are linked to increased cancer risk.
Are acrylamide levels regulated?
In the United States, the FDA regulates the amount of residual acrylamide in a variety of materials that come in contact with food, but there are currently no regulations on the presence of acrylamide in food itself. In 2016, the FDA issued guidance to help the food industry reduce the amount of acrylamide in certain foods, but these are recommendations, not regulations.
The EPA regulates acrylamide in drinking water. The EPA has set an acceptable level of acrylamide exposure, which is low enough to account for any uncertainty in the data relating acrylamide to cancer and other health effects.
In the workplace, exposure to acrylamide is regulated by the EPA and the Occupational Safety and Health Administration (OSHA).
Can I lower my exposure to acrylamide?
For most people, the major potential sources of acrylamide exposure are in certain foods and in cigarette smoke. It’s not yet clear if the levels of acrylamide in foods raise cancer risk, but for people who are concerned, there are some things you can do to lower your exposure.
Certain foods are more likely to contain acrylamide than others. These include potato products (especially French fries and potato chips), coffee, and foods made from grains (such as breakfast cereals, cookies, and toast). These foods are often part of a regular diet. But if you want to lower your acrylamide intake, reducing your intake of these foods is one way to do so.
The FDA’s advice on acrylamide is to adopt a healthy eating plan, consistent with the Dietary Guidelines for Americans, that:
- Emphasizes fruits, vegetables, whole grains, and fat-free or low-fat milk and milk products.
- Includes lean meats, poultry, fish, beans, eggs, and nuts.
- Is low in saturated fats, trans fats, cholesterol, salt (sodium), and added sugars.
This type of diet is likely to have health benefits beyond lowering acrylamide levels.
Acrylamide has been detected in both home-cooked and in packaged or processed foods. Acrylamide levels in foods can vary widely depending on the manufacturer, the cooking time, and the method and temperature of the cooking process. Since acrylamide is formed from natural chemicals in food during cooking, acrylamide levels in cooked organic foods are likely to be similar to levels in cooked non-organic foods.
When cooking at home, some methods may lower the acrylamide levels produced in certain foods.
For potatoes, frying causes the highest acrylamide formation. Roasting potato pieces causes less acrylamide formation, followed by baking whole potatoes. Boiling potatoes and microwaving whole potatoes with skin on does not create acrylamide.
Soaking raw potato slices in water for 15 to 30 minutes before frying or roasting helps reduce acrylamide formation during cooking. (Soaked potatoes should be drained and blotted dry before cooking to prevent splattering or fires.)
Storing potatoes in the refrigerator can result in increased acrylamide during cooking. Therefore, store potatoes outside the refrigerator, preferably in a dark, cool place, such as a closet or a pantry, to prevent sprouting.
Generally, acrylamide levels rise when cooking is done for longer periods or at higher temperatures. Cooking cut potato products, such as frozen French fries or potato slices, to a golden yellow color rather than a brown color helps reduce acrylamide formation. Brown areas tend to have more acrylamide.
Toasting bread to a light brown color, rather than a dark brown color, lowers the amount of acrylamide. Very brown areas contain the most acrylamide.
Acrylamide forms in coffee when coffee beans are roasted, not when coffee is brewed at home or in a restaurant. So far, scientists have not found good ways to reduce acrylamide formation in coffee.
Not smoking and avoiding secondhand smoke are other ways to potentially reduce your exposure to acrylamide, as well as to many other potentially harmful chemicals.