Dechlorane plus and other flame retardants in tree bark from the northeastern United States.

Previous work has shown that certain parts of the Great Lakes region are polluted with Dechlorane Plus (DP), a highly chlorinated flame retardant that was used as a replacement for Dechlorane/Mirex. It was suspected that a source of DP to the environment might be its manufacturing facility located in the city of Niagara Falls, New York. To confirm this source location and to determine DP's spatial distribution, 26 tree bark samples were collected in triplicate from the northeastern United States, and the concentrations of DP and several brominated flame retardants (BFRs) were measured. Most concentrations of DP in tree bark were found to be much higher than those of the BFRs. The highest DP concentrations were >100 ng g(-1) bark in the city of Niagara Falls, dropping rapidly with distance from the potential source. A simple one-dimensional, Gaussian diffusion model was used to explain the spatial distribution of DP and to locate the source. The calculated source location was <7 km away from the DP manufacturing plant in Niagara Falls, New York.