Distribution of toxic coplanar PCBs and PCDD/PCDF in pine needles from the Swedish environment - evaluation of data and identification
Öberg, T., Warman, K., Bergström, J.
Organohalogen Compounds 1, 449-452 (1990).

Abstract
Environmental samples from different areas of Sweden indicate a widespread contamination of toxic coplanar PCBs. Uncontrolled combustion (e.g. fires) is a likely source.

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