Caveat Emptor: They found a correlation, not a causative mechanism. But Polybrominated Diphenyl Ethers (PBDEs, yum!) have structures that can mimic endocrine hormones. Because hormones signal at very low doses and continuously, our whole toxicological risk testing structure of looking for acute effects at high doses and trying to extrapolate those effects to low doses is flawed for endocrine disrupting compounds. We are finally beginning to see some new research, especially with other toxics such as Bisphenol A, which test for chronic conditions and subtle gene and hormonal signalling effects at low doses. After all, small changes in hormone regulation especially at childbirth and a young age can have very serious effects later on in life.
A mysterious epidemic of thyroid disease in cats may be linked to flame retardants common in carpets, foam furniture and mattresses, according to U.S. Environmental Protection Agency researchers, who suggest that scientists have underestimated the damaging health risk the chemicals pose to humans.
The research, published Wednesday in the journal Environmental Science and Technology, does not prove these compounds, known as PBDEs, caused the rash of hyperthyroidism in the nation’s household cats over the past 30 years.
Rather, it lays out a hypothesis, showing that cats are heavily contaminated by these compounds, which leach from household products and are found everywhere, particularly household dust. Cats, meticulous cleaners, ingest PBDE-contaminated dust daily.
The case of fire retardants is especially difficult because they save many lives, so manufacturers can always point to that fact and resist change. The logical fallacy, however is as follows:
- Fire retardants save lives (therefore good)
- PBDEs are fire retardants
- Therefore, PBDEs are good!!
The search for a safer fire retardant needs to continue, and will not happen unless the old ones are under pressure of being phased out.