14The transport of discarded electronic and electrical appliances (e-waste) to developing regions has 15 received considerable attention, but it is difficult to assess the significance of this issue without a 16 quantitative understanding of the amounts involved. The main objective of this study is to track the 17 global transport of e-wastes by compiling and constraining existing estimates of the amount of e-waste 18 generated domestically in each country MGEN, exported from countries belonging to the Organization for 19Economic Cooperation and Development (OECD) MEXP, and imported in countries outside of the OECD 20 MIMP. Reference year is 2005 and all estimates are given with an uncertainty range. Estimates of MGEN 21 obtained by apportioning a global total of ~35,000 kt (range 20,000-50,000 kt) based on a nation's gross 22 domestic product agree well with independent estimates of MGEN for individual countries. Import 23 estimates MIMP to the countries believed to be the major recipients of e-waste exports from the OECD 24 globally (China, India and five West African countries) suggests that ~5,000 kt (3,600 kt -7,300 kt) may 25 have been imported annually to these non-OECD countries alone, which represents ~23% (17% -34%) of 26 the amounts of e-waste generated domestically within the OECD. MEXP for each OECD country is then 27 estimated by applying this fraction of 23% to its MGEN. By allocating each country's MGEN, MIMP, MEXP and 28 MNET = MGEN + MIMP -MEXP, we can map the global generation and flows of e-waste from OECD to non-29 OECD countries. While significant uncertainties remain, we note that estimated import into seven non-30 OECD countries alone are often at the higher end of estimates of exports from OECD countries. 31 32 2