THE ROLE OF THE ATMOSPHERE IN GREAT-LAKES CONTAMINATION

Certain implications are discussed of the data in a recent report of a tmospheric deposition rates to the Great Lakes by Hoff et al. (Atmosph eric Environment 30, 3505-3527, 1996). An analysis of the data suggest s that for many persistent, volatile organic chemicals concentrations in water are close to a state of long term (several years, within a fa ctor of approximately five) equilibrium with the atmosphere, but are i n a constant state of short-term seasonal adjustment. Under these near -equilibrium conditions the actual magnitude of air to water loadings become relatively unimportant as determinants of lake ecosystem contam ination, and the significance of land-based loadings is reduced. Succe ss in decontaminating or restoring the Great Lakes is becoming increas ingly dependent on atmospheric concentrations and thus on the processe s which determine these concentrations. (C) 1997 Elsevier Science Ltd.