Polybrominated diphenyl ethers (PBDES): Environmental exposrue assessment and evaluation of the role of PBDES in human thyroid dysfunction

ENSC 501: Independent Study Project; April 2009

Flame retardants are ubiquitous protective compounds, large quantities of which are produced all over the globe. These chemicals are, however, gaining recognition as chemicals of concern due to their emergence in the environment. Polybrominated diphenyl ethers (PBDEs), a type of brominated flame retardant, are showing up in natural media such as air, sediment, soil, as well as in the tissues of biota and humans. It is well established that PBDEs are persistent, bioaccumulative chemicals. This has led some researchers to compare PBDEs to PCBs, a previously banned persistent contaminant. The correlation between these two contaminants in terms of chemical structure, environmental transportation and storage, and bioaccumulative tendencies has raised a red flag about the future of PBDEs. Although some headway has been made into banning certain types PBDEs in North America and Europe, global production has continued. Increased demands for protective flame retardants over the past 25 years have meant more PBDE production; production trends are reflected in the continually increasing concentrations of PBDEs in the environment. The prevalence of PBDEs in environmental compartments is undeniable, but the risk they pose to the health of biota and humans is not as clear. This review examined the existing literature on PBDEs in a holistic manner. It was found that gaps in the research, in addition to a general lack of epidemiologic studies are limiting the scientific conclusions that can be drawn about the health effects of PBDEs.

School of Environmental Studies