What is acrylamide? Is it carcinogenic?
Related cancers: Although an acrylamide-cancer connection in humans has not been established with certainty, the level of suspicion is high because under laboratory conditions in rats and mice, the following cancers have been associated with acrylamide: adrenal pheochromocytomas and mesotheliomas in the testes; adenomas in the pituitary and mammary glands; adenocarcinomas of the clitoris, uterus, and thyroid gland; squamous cell carcinoma of the skin; and adenomas of the lung.
Definition: Acrylamide is a compound of carbon, hydrogen, nitrogen, and oxygen resulting in the chemical formula, C3H5NO. This white, odorless, and crystalline compound is soluble in water, ethanol, ether, and chloroform, accounting for not only its many industrial uses but also its potential for uncomplicated entry into the human body. Many of its industrial and agricultural uses require the conversion of acrylamide to the polymer \polyacrylamide.
Exposure routes: Experimentally in rats and mice, cancer-inducing exposure routes include administration in the drinking water, intraperitoneal injection, and topical application. In humans, during everyday activity and work, acrylamide gains entrance through unbroken skin, mucous membranes, lungs, and the gastrointestinal tract. The primary occupational exposure routes are skin contact and through the inhalation of dust and vapor.
Where found: Acrylamides are used in the treatment of wastewater, drinking water, and sewage; in the production of paper, plastics, and dyes; and in the manufacture of permanent press fabrics, adhesives, and food packaging. It is also fundamental to ore processing. Acrylamide finds its way into a number of everyday products such as building materials, contact lenses, textiles, soap, food, and gelatin capsules. Acrylamides have also established a place on people’s dining tables: It is found in fried and baked goods, coffee, olives, and prune juice. Smoking is also a major acrylamide producer.
Some acrylamide contaminates drinking water because of its use in water treatment facilities, but curiously, the amount of acrylamide in a large order of fast-food french fries is more than three hundred times what the US Environmental Protection Agency allows in a single glass of water. This pervasiveness of acrylamide prompted Dale Hattis, a risk analysis expert at Clark University, to speculate that “acrylamide causes several thousand cancers per year in Americans.” However, such a claim is unfounded. and tests have not indicated conclusively that acrylamides cause cancer.
Additionally, polyacrylamide, the polymer of acrylamide, finds widespread global use in pesticides and in soil treatment formulations. This has resulted in notable residues of polyacrylamide in the most widely consumed vegetables such as potatoes and grains. There is little government oversight or measurement of polyacrylamide in foods.
At risk: Because of its almost ubiquitous presence at the dinner table and its known neurotoxic and carcinogenic potential, acrylamide poses a health risk to humans. Microwaving, baking, and frying will produce acrylamide, and as the food continues to cook, ever larger amounts of acrylamide are produced. As the risk potential for acrylamides in foods becomes more publicized, some steps are under way to modify food production methods, such as using vacuum frying at lower temperatures. Raw or boiled foods pose little risk for acrylamides. The Food and Drug Administration recommends lightly toasting bread and not overfrying foods to avoid high levels of acylamide exposure.
Workers engaged in oil drilling, paper and pulp manufacture, general construction, plastics manufacture, mining, food processing, textile and cosmetics processing, and agricultural industries are at increased risk of acrylamide exposure.
Etiology and symptoms of associated cancers: Although research has not firmly established the acrylamide-cancer connection in humans, there is no question that acrylamide is a serious neurotoxin. Depending on dosage levels, exposure can cause damage to the male reproductive glands, skin, and eyes. Additionally, it may result in urinary incontinence, numbness, weakening in the legs and hands, and irritation of the mucous membranes.
The National Institute for Occupational Health and Safety (NIOSH) lists the common acrylamide exposure symptoms in an industrial setting: irritation of the eyes and skin, ataxia, numbness of the limbs, paresthesia, muscle weakness, absent deep tendon reflex, hand sweating, lassitude (weakness, exhaustion), drowsiness, and reproductive effects. The institute further cautions that acrylamide is a potential occupational carcinogen.
History: Production of acrylamide in the United States exceeds one million pounds per year. It was not until 2002 that Swedish scientists found high levels of acrylamide in certain fried and baked starchy foods. In the same year, the Center for Science in the Public Interest in the United States reported finding high levels of acrylamide in popular brands of snack chips, french fries, taco shells, and breakfast cereals. Government action concerning these findings has been very slow, but in 2005 the California attorney general filed a lawsuit requiring a warning label for french fries and potato chips. In 2013, the FDA issued a consumer warning about acrylamide in common foods and provided tips for avoiding the chemical while cooking.
Although NIOSH considers the compound dangerous to life and health, the FDA allows acrylamide to be used for packaging, in plastics that are in contact with food, and in treating food to maximum levels ranging up to 0.20 percent.
Although research has firmly established the cancer-acrylamide connection in rats and mice, the findings are still mixed in human studies. Some experts claim the very pervasiveness of acrylamide in the Western diet confuses the results.
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