Studies on the Behaviour of Water‐endangering Substances in Plants for the Biological Cleaning of Municipal Waste Waters. Part 1: Bromoxynil

摘要

AbstractThe behaviour of the herbicide bromoxynil (3,5‐dibromo‐4‐hydroxybenzonitrile), labelled with82Br, is investigated in an activated sludge plant on the laboratory scale with municipal wastewater. Only 5 of bromoxynil present in a concentration of 5 mg/l are degraded after preadaption of activated sludge for some weeks. The known hydrolysis products 3,5‐dibromo‐4‐hydroxybenzamide and 3,5‐dibromo‐4‐hydroxybenzoic acid were identified as degradation products. In addition, 1.9±0.9 of the quantity of82Br appeared in the solution as Br−by debromination. Moreover, a pronounced adsorption of the active substance on activated sludge occurs. Its activity amounts to about 130 of the initial acti