Cat diseases associated with PBDE chemicals in flame retardants

William Atkins
Sunday, 19 August 2007 20:55

Science - Health

An increasing number of cats are being diagnosed with thyroid diseases, and it is possibly linked to chemicals in flame retardant products in the house. Could such chemicals harm humans?

U.S. Environmental Protection Agency (EPA) scientists have suggested that chemicals in flame retardant products, such as carpets, furniture, mattresses, electronics, fabrics, and other common household items, could be more dangerous than thought. The danger is thought to be related to cats that are increasingly being inflicted with various thyroid diseases. But, the danger could lie within humans, too.

Within their report, the researchers state: “Our results support the hypothesis that cats are highly exposed to PBDEs; hence, pet cats may serve as sentinels to better assess human exposure and adverse health outcomes related to low-level but chronic PBDE exposure.”

The EPA researchers, associated with the EPA’s National Health and Environmental Effects Laboratory, University of Georgia, and Indiana University, state that their research does not prove the link between chemical in flame retardants and the higher incidences of cats with thyroid diseases.

However, their research does indicate that some type of association may be present in cats with thyroid conditions and those who are also contaminated with polybrominated diphenyl ethers (PBDEs).

Janice A. Dye, one of the EPA scientists with the study, along with her associates said that feline hyperthyroidism was a rare illness in cats before 1980. Also, the use of PBDEs increased dramatically since the 1980s. Now, in the mid-2007s, feline hyperthyroidism is one of the leading health problems in older cats.

These two facts are not necessarily related. Additional research will be performed to verify or deny such an association.

Twenty-three house cats were tested. PBDE concentrations were twenty to one-hundred times higher than the average concentration in people living in North America. Dye states that their “study ‘points the finger at the association’ between the endocrine-disrupting compounds and the disease.”

The health risk from PBDEs has been noticed since 1998 when Swedish scientists found PentaBDE, a type of PBDE, within human breast milk. Since then, there is increasing scientific evidence that PBDEs cause toxicity in the liver, thyroid, and within the nervous system of humans and other animals.

The EPA group’s article (“Elevated PBDE Levels in Pet Cats: Sentinels for Humans?”) was published in the Wednesday, August 15, 2007 Web issue of the journal Environmental Science and Technology. Besides Dye, the other collaborators in the study are Marta Venier, Lingyan Zhu, Cynthia R. Ward, Ronald A. Hites, and Linda S. Birnbaum.

Industry representatives counter that it is only speculation to associate PBDEs with cat illnesses.

However, small animals like cats are similar in size to small children. Both can become contaminated with PBDEs due to their close proximity to carpets (as they walk and crawl) and due to the large amounts of time they spend indoors (where PBDEs are concentrated the most).

Studies are beginning to research the affects of PBDEs on human health. Some PBDEs have been banned, however, others continue to be used in household appliances and objects.

In fact, according to Inside Bay Area (California) staff writer Douglas Fischer, “Flame retardants linked to illness in cats”, the United States uses one-half of the world’s supply of PBDEs. Estimates are that U.S. citizens have ten to one-hundred times higher concentrations of PBDEs in their blood over those people in Japan and European countries.