Suzuki, G.; Michinaka, C.; Takagi, H.; Sakai, S. (2017) Presented at 4th International Conference on Final Sinks, Kyoto, Japan, October 25, 2017
INTRODUCTION
In 2011, a joint World Health Organization (WHO) and United Nations Environment Programme (UNEP) expert recommended the use of the WHO Toxicity Equivalency Factor (TEF) scheme for brominated dioxins for human health risk assessment (van den Berg et al. 2013). This is because brominated dioxins such as polybrominated dibenzo-p-dioxins (PBDDs), dibenzofurans (PBDFs), and coplanar biphenyls (Co-PBBs) are considered to have similar toxicity profiles to chlorinated dioxins (Birnbaum et al. 2003) listed as unintentionally released persistent organic pollutants (POPs) we have to eliminate/reduce these negative legacies during the product lifecycle. Some of them can be present as low-level impurities in commercial mixtures of brominated flame retardants (BFRs) such as polybrominated diphenylethers (PBDEs) (Hanari et al. 2006). On the other hands, brominated dioxin-like compounds in other BFRs have never been reported before.
In this study, we investigated the dioxin-like activities of the BFRs and phosphorus-containing flame retardants (PFRs) containing also impurities in order to evaluate the possibility of the dioxinlike compounds in the FR. First, we evaluated their dose-response relationships by using authentic standards. Secondly, we investigated the change of the dioxin-like activity for the FR standards after the clean-up treatment with silica gel columns impregnated with 55% sulfuric acid in order to evaluate whether the dioxin-like compound detected in the FR is the sulfuric-acid persistent compound.