Aquatic photodegradation of albendazole and its major metabolites. 2. Reaction quantum yield, photolysis rate, and half-life in the environment

The photolysis rate constant (k(p)) of albendazole (ABZ) and its three major metabolites, albendazole sulfoxide (ABZSO), albendazole sulfone (ABZSO2), and 2-aminoalbendazole sulfone (ABZ2NH2), measured in a tube (11 X 100 mm) (see part 1 of this series) will essentially reflect a faster rate than the expected rate (k(pE)) at the surface of flat water body in the environment. The internal reflections increase the incident sunlight in a test tube. In this experiment, the photolytic reaction quantum yield (PHI) and photolysis rate constant, k(p), measured in a quartz tube were converted to reflect the environmentally relevant rates. A maximum environmental photolysis rate constant (k(pE)), a minimum half-life, and their respective values for summer and winter seasons for ABZ and its metabolites were estimated.