Story of Brominated Flame Retardants: Substance Flow Analysis of PBDEs from Use to Waste

The main goal of this study was to understand the fate of brominated flame retardants (BFRs), particularly PBDEs, during the life cycle of BFR-containing products. PBDEs were added to the Stockholm Convention list of chemicals to be eliminated. The migration of BFRs from products and their partitioning to dust results in human exposure through dust ingestion and inhalation. Moreover, during the use of BFR-containing products, direct contact with these products can lead to human exposure. With the proliferation of BFRs as PBDE alternatives, identifying the product source of these chemicals is essential to minimize the risk associated with the exposure. In this research, a rapid and non-destructive method was developed to identify and to some extent quantify BFRs used in consumer products. The next step towards the management of these chemicals is to estimate the time course by which these chemicals will remain in use. Based on consumption patterns of PBDE-containing products, the time-dependent stock of PBDEs contained in in-use products was estimated for the U.S. and Canada from 1970 to 2020. Considering only the first lifespan of products, the stock of PBDEs was estimated to be ~120,000 t in 2014 and it is estimated that by 2020, ~ 60% of this stock will remain in products in the use phase. Although the flow of PBDE-containing products to the waste phase started to decline following 2008, this flow will continue as these products reach their end of life and enter the waste phase. As these products leave the first use phase, their accumulation in storage and waste phases will continue to act as sources of PBDEs to the surrounding environment with annual emission rate of 0.3-4 tonnes路y-1 between 1970 and 2020. Thus, the management of BFR-containing products deserves more attention as the mismanagement of these products, especially waste electronics, has led to undesirable and irreversible global environmental consequences. The results of this dissertation suggest that current waste management programs in the U.S. and Canada are challenged to deal with influx of e-waste in the near future.Ph.D