Industrial Chemical Contamination

Mercury, lead, cleansing agents, and other chemicals used by industry sometimes contaminate foods and lead to foodborne illness. Mercury poisoning has occurred in people who consumed fish from waters contaminated with mercury. Plants grown near a metal refinery, or even next to roads with heavy traffic, may have unsafe levels of lead. In restaurants and institutions, health department standards require a completely separate storage area for cleaning agents, well away from foods. Other chemicals that have been found to contaminate foods are polychlorinated biphenyls (PCBs), polyvinyl chloride (PVC), polycyclic aromatic hydrocarbons (PAHs), and some chemicals found in fish.

Polychlorinated Biphenyls (PCBs)

For half a century, PCBs were used in industry, especially as cooling oils for electrical transformers. The manufacture of this industrial chemical was banned in 1979 by the Environmental Protection Agency when it was discovered that it may cause cancer when taken in through contaminated foods.

Polyvinyl Chloride (PVC)

Food storage containers are often made with polyvinyl chloride, a compound found to migrate from plastic containers into food. It was discovered that large amounts of PVC ingested or inhaled by animals often resulted in cancer, but no strong links have been discovered between the vinyl chloride from food containers and cancer in humans. As with PCBs, however, occupational exposure to vinyl chloride is associated with an increased risk of certain cancers.

Polycyclic Aromatic Hydrocarbons (PAHs)

Although cigarette smoke is known to be a common source of a PAH (benzo[a]pyrene), PAHs are also found at low levels in a wide variety of foods. The compounds enter the food supply primarily through contaminated soil, smoke-curing, charcoal-broiled meats, polluted air or water, and synthesis by plants and microorganisms. Large concentrations of PAHs have been linked to cancer.

Contaminated Fish

Eating contaminated fish on a regular basis over a long period of time may increase a person’s risk for cancer. People particularly at risk are recreational anglers, Native Americans, and lower-income families that consistently fish in contaminated waters. Chemicals of concern include mercury, PCBs, dioxin, DDT (an insecticide), and certain pesticides. Bans and restrictions exist in various waters throughout the states, and lists of these lakes, streams, canals, and ocean areas are available from local health departments or state government agencies.