The pine needle as a monitor of atmospheric pollution

Abstract

THE concentrations of toxic chemicals in the atmosphere and their deposition and long-range transport are becoming one of the more prominent issues in environmental chemistry. In 1986, a report1 was published documenting the levels of DDT (p,p′-dichlorodiphenyl-trichloroethane) and other organochlorine contaminants in the muscle tissue of pike and herring from areas in and around Sweden. There has previously been a downward trend in residue levels but in parts of Sweden and the south Baltic during 1983-84, the ratio of p,p′-DDT to its metabolites significantly increased, indicative of freshly released DDT from a source south of Sweden. (DDT has been restricted or banned in most of Europe since the 1970s.) It was established2 that an increased forest spraying program using DDT was implemented in 1984 in the southern part of East Germany. DDT can be transported over very long distances3 and in light of the above there is a need for an extensive field programme to monitor such pollution and locate its source. Here we test the hypothesis that the pine needle is a suitable monitoring matrix and delineate the extent of the DDT contamination of 1983–84. We conclude that the pine needle is a suitable monitor of atmospheric pollution and that because of the widespread distribution of the pine, it may provide time-series data for much of the Northern Hemisphere from which trends in atmospheric pollution may be discerned.