Atmospheric deposition of PBDEs to the Great Lakes featuring a Monte Carlo analysis of errors

The first estimates of atmospheric deposition of polychlorinated diphenyl ethers (PBDEs) into the Great Lakes are presented. Precipitation samples were collected monthly from 2005 to 2006 at five sites located in the Great Lakes region. Volume weighted mean concentrations of total PBDEs in precipitation ranged from 94 +/- 19 ng L(-1) at the urban site of Chicago to 0.65 +/- 0.14 ng L(-1) for the rural site of Sturgeon Point Using gas and particle phase concentrations previously obtained in our laboratory and concentrations in precipitation measured in this study, the total annual net mass transfer rates to each lake and their relative errors were calculated using Monte Carlo analysis. The highest net mass transfer rates for BDE-47, and total PBDEs were measured for Lake Michigan (150 +/- 40 and 310 +/- 79 kg y(-1), respectively) while the highest net mass transfer rate for BDE-209 was measured for Lake Erie (79 +/- 56 kg y(-1)). We found good agreement between atmospheric and sediment net mass transfer rates for Lake Superior, but we found a significant imbalance of BDE-209 for the other two lakes and of BDE-47 for Lake Michigan. These findings suggest that Chicago might be a preferential source of BDE-47 to Lake Michigan and that Cleveland might be a preferential source of BDE-209 to Lake Erie.