Nomination Summary for Decabromodiphenylethane (DBDPE) (N21017)
Nominated Substances: 1,2-bis(pentabromophenyl)ethane
Nomination Date: 08/14/2010
Nominator: Private Individual
Rationale: Decabromodiphenylethane (DBDPE, CASRN 84852-53-9) is a brominated flame retardant used in plastic and textile applications ranging from consumer electronics to wire and cable to textiles. Since deca-BDE, the number two flame retardant in global volume sold, is being phased out in the United States and the EU, and DBDPE appears to be a major replacement for deca-BDE, there is rapidly increasing demand for DBDPE which had been predicted to result in increasing DBDPE contamination in the future (Luo et al. 2009). DBDPE has been detected in both environmental and biotic media. DBDPE has been detected at significant levels in domestic dust. Toxicity of DBDPE has been suggested by the few studies that have been carried out to date. Nakari and Huhtala 2009 assessed DBDPE toxicity both in vivo and in vitro using the freshly separated fish hepatocyte assay and standardized water flea and zebrafish egg-larvae tests. The fish hepatocyte assay, produced a clear dose-response curve in the presence of DBDPE and showed that DBDPE is estrogenic. In vivo tests showed that DBDPE was acutely toxic to water fleas. Moreover, DBDPE reduced the hatching rates of exposed zebra-fish eggs and raised significantly the mortality of hatched larvae. The authors conclude that because there is limited information available on the effects of DBDPE on the aquatic environments, it is crucial to obtain more data on the effects and effective concentrations of DBDPE along with its occurrence in the environment. Such data would enable reliable assessments of the risks posed by this flame retardant. In a study by Hardy et al. 2002, with funding from Albemarle, DBDPE administered to rats for 90 days was associated with an increased size of the liver relative to body weight. A newer study funded by Albemarle (Hardy et al. 2010) concluded that there was no evidence of maternal toxicity, developmental toxicity, or teratogenicity in rats or rabbits treated with DBDPE at dosage levels up to 1,250 mg/kg per day. However, these are gross endpoints. They did not measure neurotoxicity in either the dams or the offspring and no immune endpoints or measures of the effects on the endocrine system were given. There was no assessment of specific pathways known to be affected by these chemicals for any system. This study could be considered a dose-ranging study for future, more relevant studies. Hardy ML, Margitich D, Ackerman L, Smith RL. (2002); Int J Toxicol. 21:165-170. Hardy ML, Mercieca MD, Rodwell DE, Stedeford T. (2010); Birth Defects Res B Dev Reprod Toxicol. 89(2): 139-146. Luo XJ, Zhang JL, Wu JP, Luo Y, Chen SJ, Mai BX, Yang ZY (2009); Environ Sci Technol. 43: 306-311. Nakari T, Huhtala S. (2009); Environ Toxicol. 25: 333-338.
NTP Principles: not specified