Emission and gas-particle partitioning characteristics of atmospheric halogenated and organophosphorus flame retardants in decabromodiphenyl ethane-manufacturing functional areas*

The emission and gas-particle partitioning characteristics in various functional areas of production lines are still unknown. However, flame-retardant manufacturing activities are the primary emission source of flame retardants. Thus, fine particles and gases were investigated in three functional areas of a decabromodiphenyl ethane production line, i.e., polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), dechlorane plus (DPs), and organophosphorus flame retardants (OPFRs) in a flame-retardant manufacturing factory. High levels of PBDEs (8.02 x 103-4.16 x 104 pg/m3), NBFRs (6.05 x 103-1.92 x 105 pg/m3), and DPs (89.5-5.20 x 103 pg/m3) were found in various functional areas, suggesting manufacturing activities were a primary emission source. In contrast, OPFRs were derived from long-range transport or other non-industrial sources. Varied concentrations of PBDEs, NBFRs, and DPs were observed in different production lines, higher in the reaction zone area than others. As the predominant compounds, decabromodiphenyl ether, decabromodiphenyl ethane, syn-DP, and tris(chloropropyl) phosphate accounted for 54.7%, 89.3%, 93.4%, and 34.7% of PBDEs, NBFRs, DPs, and OPFRs, respectively. Three models were used to predict the gas-particle partitioning of the halogenated flame retardants emitted from manufacturing activities. The Li-Jia Empirical Model predicted the gas-particle partitioning behavior well. This research shows that the adsorption-desorption process of the halogenated flame retardants between the gaseous and particulate phases did not reach equilibrium.

Automated summary

The emission and gas-particle partitioning characteristics in various functional areas of flame-retardant production lines were investigated. High levels of PBDEs, NBFRs, and DPs were found in the functional areas, indicating manufacturing activities as the primary emission source. OPFRs were found to be derived from sources other than industrial activities. The gas-particle partitioning behavior of the emitted flame retardants was predicted using three models, and the Li-Jia Empirical Model showed good performance.