Konferansebidrag og faglig presentasjon
Long-range transport of e-waste: Part 2. Exploring the potential implications of trans-boundary e-waste exports on chemical emissions, fate and exposures.
Poster presented at SETAC Europe 24th Annual Meeting, Basel, Switzerland, 11-15 May 2014.
Sammendrag: Trans-boundary movement of e-waste and the associated contaminants (e.g., polychlorinated biphenyls, halogenated flame retardants, metals) has emerged as an important research topic in the last decade. Several monitoring studies published in the peer-reviewed literature have documented elevated levels of various industrial-use organic contaminants (IUOCs) in the atmosphere near known or suspected e-waste receiving and processing sites in Asia. Surprisingly high concentrations of polychlorinated biphenyls in the atmosphere were also reported offshore of West Africa. Emissions of IUOCs linked to trans-boundary movement of e-waste have implications for chemical fate and exposure at local, regional and global scale. For example, the transfer of e-waste from temperate climates to tropical regions could lead to enhanced emissions simply through temperature-related increases in passive volatilization from open landfill sites. The main objective of this study is to develop emission scenarios for selected IUOCs considering the generation and transport of e-waste and simulate and compare chemical fate and transport using an evaluative modeling approach. All simulations were conducted using BETR-Global 2.0 (https://sites.google.com/site/betrglobal/), a chemical fate model which divides the globe into 288 zones (15o x 15o). This spatial resolution is deemed suitable for assessments at the regional as well as global scale. Breivik et al. (SETAC 2014) present an inventory of the global generation and trans-boundary exports of e-waste towards non-OECD countries, with an emphasis on locations in sub-tropical and tropical regions. This inventory along with the physical-chemical property data of selected IUOCs (e.g., partition coefficients, degradation rate constants) are the key inputs to the model simulations. Model output under various emission scenarios are compared in terms of overall persistence (POV) at the global scale as well as in terms of long-range transport potential (LTRP) at regional and global scale (e.g., atmospheric deposition of IUOCs in remote regions). The model outputs are also used to assess the potential implications for chemical exposure at regional and global scale under the various scenarios.