An informal study by an environmental group has found higher concentrations of many synthetic chemicals in pets than in people, less than a year after similar research by the Environmental Protection Agency specifically on flame retardants in cats.
The Environmental Working Group, a nonprofit in Washington, D.C., analyzed blood and urine samples from dogs and cats. Data on mean concentrations of chemicals in adult humans came from previous national studies by the Centers for Disease Control and Prevention and by the EWG.
The recent EWG study found that the mean serum concentration of polybrominated diphenyl ethers, or flame retardants, in samples from 17 cats was 23.4 times as high as in people. Mean concentration of mercury in samples of whole blood from 10 cats was 5.4 times as high. Mean serum concentration of perfluorochemicals, stain- and grease-proof coatings, in samples from five dogs was 2.4 times as high.
"This study shows that our pets are susceptible to the absorption of potentially harmful chemicals from our environment," said Dr. John Billeter, founder of Hanover Animal Hospital in Virginia, which collected the blood and urine samples. "Perhaps even more troubling is that these chemicals have been found in higher levels in pets than in humans, implying potential harmful consequences for their health and well-being—and the need for further study."
The EPA study "Elevated PBDE levels in pet cats: sentinels for humans?" appeared in the Sept. 15, 2007, issue of Environmental Science & Technology. The study of 23 cats found that PBDE serum concentrations were 20- to 100-fold higher in cats than median concentrations in adult humans.