Health Effects from PBB Exposure

How did exposure to PBBs affect people?

Some Michigan residents who were exposed to polybrominated biphenyls (PBBs) in the 1973-74 contamination incident complained of nausea, abdominal pain, loss of appetite, joint pain, fatigue, and weakness. It could not clearly be determined that PBBs were the cause of these health problems. There is stronger evidence that PBBs may have caused skin problems, such as acne, in some people who ate contaminated food. Some employees of chemical factories who were exposed to PBBs by breathing and skin contact also developed acne (ATSDR 2004).

More recent studies have suggested that PBBs may interact with the endocrine system (ATSDR 2004). The endocrine system is a group of organs and glands, including the adrenal glands, which work to produce hormones. The endocrine system plays an important role in controlling your body’s metabolism, growth and development of infants and children, and reproduction in adults.

For additional information:

ATSDR ToxFAQs^TM for Polybrominated Biphenyls (PBBs) - Frequently Asked Questions about PBBs

 How do I know that I’ve been exposed to PBBs?

There are tests that can measure PBBs in blood, body fat, and breast milk. Although PBBs are a chemical mixture, most tests just measure one chemical, PBB-153. These tests can tell whether you have been exposed to PBBs, but cannot tell the exact amount or type of commercial mixture that you were exposed to (Sjödin et al. 2008). These tests cannot tell whether any health problems you have now or in the future are due to any PBB exposure. These tests are not usually available at the doctor’s office, but samples can be sent to laboratories that have the necessary equipment. MDHHS Bureau of Laboratories no longer provides PBB testing; however, Emory University may provide testing.

While everyone might have some level of PBBs in their body because of how commonly they were used prior to 1976, your risk of exposure was increased if you:

• Lived or worked on a farm in Michigan in 1973-1974.
• Ate PBB-contaminated beef, pork, lamb, chicken, dairy products, or eggs during 1973-1974 from Michigan farms.
• Worked for the Michigan Chemical Company (also known as Velsicol Chemical Company) at their factory in St. Louis Michigan, were the spouse or child of a factory worker, or lived near that factory.

Are people in Michigan still being exposed to PBBs?

The United States banned the manufacture of PBBs in 1976. Today, the general population can only be exposed from contact with historical releases or products (ATSDR 2004). Persons exposed to PBBs in the past may still have measurable levels in their serum and fat. Michigan residents of the lower peninsula, especially those who live near areas contaminated during the 1973-74 incident, may still have very low exposures (ATSDR 2004). Older people tend to have higher levels of PBBs in their blood due to their presumed past exposure (Sjödin et al. 2008). Overall, the amount of PBBs in the environment has decreased since the 1970s and only very low levels persist (ATSDR 2004).The U.S. Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey measured PBB in serum from a representative sample of the U.S. general population between 2005 – 2014 and found few people who had measurable levels of PBBs.

Do PBBs leave the body after exposure?

Yes, but slowly. As of 2020, there is no known medical treatment that will lower PBB amounts in the human body, although this may be a topic of additional research.

How long does it take for PBBs to leave the body?

 PBBs leave the body slowly, with people losing around half of the PBBs in their body about every 10 to 15 years. The Agency for Toxic Substances and Disease Registry’s (ATSDR) Toxicological Profile for Polybrominated Biphenyls (PBBs) reports that researchers estimate that it would take more than 60 years for the more highly exposed Michigan residents’ PBB levels to drop below the detection limit of 1 part per billion. Smoking, body weight, weight loss, and (among women) pregnancy and breastfeeding can affect how quickly PBBs leave the body.

Do PBBs cause cancer?

It is not known whether PBBs can cause cancer in people. Studies show that they can cause liver cancer in rats and mice (NTP 1983). In 2016, The U.S. Department of Health and Human Services National Toxicology Program (NTP) determined that PBBs may reasonably be anticipated to cause cancer. In 2015, the International Agency for Research on Cancer (IARC) concluded that “…PBBs are probably carcinogenic to humans.” Both agencies based their conclusions on PBBs’ similarity to another group of cancer-causing chemicals, polychlorinated biphenyls (PCBs).

Are there MDHHS health recommendations?

Having one of the health issues listed here does not mean that you have been exposed to PBBs. Having been exposed to PBBs does not mean that you will have one of the health issues discussed here. MDHHS recommends talking to your healthcare provider about your health concerns, having annual wellness exams, and following your healthcare provider’s recommendations for medical tests and cancer screenings.