Correspondence Comment on “Polybrominated Diphenyl Ethers Contamination of United States Food” Schecter et al. (1) conclude “... the results here demonstrate a need for understandingthe exposure of Americans to PBDEs via food” and implies a public health concern. The maximum level detected, 3078 pg/g in 1 of 2 salmon analyzed, was less than the 4000 pg/g maximum reported earlier by Hites et al. (2) for a much larger sample size (N ) 500 salmon). In response, Health Canada stated that salmon were safe for human consumption and, in fact, beneficial due to their omega-3 fatty acid content (3). Health Canada noted, “to date, there are no studies that link PBDE levels contained in food to any human health effects. Previous studies conducted on experimental animals, which had shown adverse effects related to PBDEs, involved exposure to levels that were over a million times higher than what is currently found in foods, including fish”. Thus, the Canadian Minister of Health concluded parts per trillion (ppt) levels of PBDEs do not represent a human health risk. Schecter et al. (1) highlight detection of decabromodiphenyl ether/oxide (BDE-209; Deca). However, Deca’s extensive toxicology and risk assessment database was not highlighted, and the authors missed the opportunity to put their results in context. In contrast to their general statements concerning PBDEs, Deca is not an endocrine disruptor, reproductive or developmental toxicant, or carcinogen (4). It is not “chemically and toxicologically” similar to PCBs (5). The U.S. National Academy of Sciences reviewed Deca’s toxicology, confirmed its safety in textiles, and assigned an oral reference dose (RfD) of 4 mg kg-1 day-1(6). The RfD is defined as a safe daily intake level for the most sensitive person(s) over a lifetime. Deca’s exposure assessment developed for EPA’s Voluntary Children’s Chemical Evaluation Program shows that even worst-case estimates are several orders of magnitude lower than the RfD (4, 7). The European Union’s recently completed, exhaustive 10-year risk assessment of Deca failed to identify human health risks. With today’s advanced techniques, trace analysis allows detection of virtually any substance. The authors justly note that quality control is important “when analyzing PBDE’s at ultra trace levels”. A market basket survey of Canadian foods, not cited by authors, reported significant uncertainty in PBDE analysis at low ppt levels, especially Deca, due to difficulty
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in obtaining clean laboratory blanks (8). As a result, little or no Deca was positively detected. The randomness of the present screening study’s results makes conclusions even more suspect. The paper’s call for further monitoring of U.S. foods is difficult to understand from a public health standpoint. The majority of the “PBDEs” detected are those associated with the Penta and Octa products, whose manufacture will voluntarily cease in 2004. The ppt levels detected do not represent a human health risk, a conclusion reached by more thorough assessments than that presented in this paper.
Literature Cited (1) Schecter, A.; Pa¨pke, O.; Tung, K.; Staskal, D.; Birnbaum L. Polybrominated diphenyl ethers contamination of United Sates food. Environ. Sci. Technol. 2004, 38, 5306-5311. (2) Hites, R. A.; Foran, J. A.; Schwager, S. J.; Knuth, B. A.; Hamilton, M. C.; Carpenter, D. O. Global assessment of polybrominated diphenyl ethers in farmed and wild salmon. Environ. Sci. Technol. 2004, 38, 4945-4949. (3) Health Canada. Government of Canada assures public that farmed and wild salmon are safe to consume. News Release 2004-45; available on-line August 17, 2004; http://www.hcsc.gc.ca/english/media/releases/2004/2004_45.htm. (4) Voluntary Children’s Chemical Evaluation Program (VCCEP). Data summary. Decabromodiphenyl ether (a.k.a. decabromodiphenyl oxide, DBDPO). CAS Registry No. 1163-19-5. ACC Brominated Flame Retardant Industry Panel: 1300 Wilson Blvd, Arlington, VA, December 17, 2002. (5) Hardy, M. A comparison of the properties of the major PBDE/ PBDPO commercial product to those of major PBB and PCB products. Chemosphere 2002, 46, 717-728. (6) Gardner, D. E., Walker, B., Eds. Decabromodiphenyl oxide. In Toxicological Risks of Selected Flame-Retardant Chemicals; National Academy Press: Washington, DC, 2000; Chapter 5; http://www.nap.edu. (7) Hays, S. M.; Cushing, C. A.; Leung, H. W.; Pyatt, D. W.; Holicky, K. C., Paustenback D. J. J. Children’s Health 2003, 1, 449-475. (8) Ryan, J. J.; Patry, B. Presented at the 2nd Annual Workshop on Brominated Flame Retardants in the Environment. June 5-6, 2000, Burlington, ON.
Marcia L. Hardy Health, Safety, and Environment Department Ablemarle Corporation 451 Florida Street Baton Rouge, Louisiana 70801 ES040518T
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2005 American Chemical Society Published on Web 02/12/2005
