Determination of Chlorinated/Brominated Flame Retardants and their Metabolites in Breast Milk

A method was developed for the determination of trace. amount chlorinated/brominated flame retardants and their metabolites in breast milk by gas chromatography combined with mass spectrum in negative chemical ionization mode (GC/NCI-LRMS). Chlorinated/brominated flame retardants and their metabolites were classified into netural and phenolic fractions. Neutral targets included eight brominated diphenyl ether (BDE) congeners (including BDE. 209), five MeO-BDE congeners and other new flame retardants or the metabolites. Phenolic targets referred to nine OH-BDEs congeners. The efficient separation of various neutral targets was obtained on a 30-m column (RTX-1614) and that of phenolic targets was achieved on a 30-m column (DB-5) in the optimized GC condition. In the extraction and clean. up procedures, before supersonic extracting, surrogate/internal standards were required spiking into breast milk, then the samples were separated into neutral and phenolic fractions by a liquid. liquid extraction methods. The extracts were cleaned. up further to remove other co-extracts by sulfuric acid silica prior to injection. It was noticeable that phenolic fractions required to be further derived by diazomethane before clean-up. The recoveries of decabrominated diphenyl ethers, other polybrominated diphenyl ethers, methoxyl. polybrominated diphenyl ethers, dechlorane plus and dechlorinated products, other flame retardants, hydroxylated polybrominated diphenyl ethers were 66.5%-75.4%, 84.2%-126.4%, 60.9%-115.1%, 86.7%-104.9%, 42.9%-113.8% and 64.7%-129.5%, respectively. The RSD of neutral targets were all below 22%, and those of the phenolic targets were all below 30%. The method was used for the determination of targets in breast milk from an e. waste dismantling area. The results of quality control showed the method was reliable investigation.