Photochemical degradation of dicarboximide fungicides in the presence of soil constituents

Procymidone and vinclozolin undergo photolytic reactions in the presence of organic and inorganic soil constituents. Humic and fulvic acids in aqueous solution lead to enhanced photodegradation of these chemicals. Iron oxide and titanium dioxide contribute to the disappearance of the dicarboximide fungicides due to photocatalysis. Photolysis of these compounds leads to dechlorination and isomerization.