Chemical Contaminants from Plastics in the Animal Environment.

Accidental exposure of our mice to bisphenol A (BPA) from damaged polycarbonate cages 20 y ago provided some of thefirst evidence of the harmful effects of exposure to this common chemical. Recently we found that housing mice in damagedpolysulfone cages resulted in similar harmful effects due to exposure to bisphenol S (BPS). This problem was unexpected for2 reasons. First, polysulfone is a far more chemically resistant polymer than polycarbonate. Second, BPS is not a componentin the manufacture of polysulfone. We report here our efforts to verify the source of the BPS and eliminate the exposure. Ouranalysis of new polysulfone caging materials confirmed that BPS is a breakdown product of damaged polysulfone plastic.Furthermore, we found that BPS can cross-contaminate new or undamaged cages in facilities that process damaged cagingmaterials. Neither the use of disposable cages nor replacement of caging materials used solely for our colony was sufficientto eliminate exposure effects. Only the replacement of all cages and water bottles in the facility corrected the problem andallowed us to resume our studies. Taken together, our previous and current findings underscore the concern that chemicalsfrom plastics are harmful environmental contaminants for both humans and animals. Furthermore, our results providestrong evidence that the presence of damaged plastic in a facility may be sufficient to affect research results and, by extension, animal health.