Do airborne nitrophenols contribute to forest decline?

Abstract

A hypothesis is put forward which postulates the possible contribution of photochemically formed nitrophenols to forest decline. The following steps are analysed with regard to experimental data endorsing or contradicting this hypothesis: formation of nitrophenols, enrichment in the aqueous phase, exposure of plants to nitrophenols, and their possible contribution to forest decline‐ It is shown that phytotoxic nitrophenols are formed in the troposphere and have been detected in rainwater. The gaps in our knowledge are discussed, especially with regard to accurate analytical data and subacute phytotoxicity.