Observations on persistent organic pollutants in plants: Implications for their use as passive air samplers and for POP cycling

Pine needle (Pinus sylvestris) and lichen (Hypogymnia physodes) samples from Various remote sites across Norway have been analyzed for a range of persistent organic pollutants (POPs). Results have shown differences in accumulation between species, with higher concentrations being noted in the H. physodes than the P. sylvestris. This indicates that to use vegetation as a biomonitor, intraspecies and not interspecies comparisons in vegetation pollutant loading between sites are necessary. alpha/gamma-HCH ratios were highest at colder northern sites, indicating increased distance from source areas and long-range atmospheric transport. Concentrations of PCBs 101, 118, 138, and 153 in H, physodes were found to be higher at lower temperatures. Trends between burdens of the other POPs in H. physodes or P, sylvestris and site temperature or latitude were not apparent. Plant/air partition coefficients indicate favored accumulation of PCBs in vegetation at lower temperatures and for higher chlorinated congeners.