Selective trapping of organochlorine compounds in mountain lakes of temperate areas

The study of fish concentrations and sediment inventories in 19 European hi gh mountain lakes (40-67 degreesN) shows that a fraction of organochlorine compounds (OCs), the less volatile compounds (LVC; subcooled liquid vapor p ressure less than or equal to 10(-2.5) Pa), are trapped in the higher locat ions. This general trend is not significantly influenced by possible local sources. Compound distribution is related to average air temperatures. The phase-change pseudoenthalpies calculated from the sediment inventories clos ely match the summed theoretical volatilization and dissolution enthalpies. This fractionation effect is responsible for the accumulation of high conc entrations of the LVC, the more persistent and toxic according to literatur e data, in organisms inhabiting sites far from the locations of synthesis o r use.