Behavior of [14c]‐4‐nitrophenol and [14c]‐3,4‐dichloroaniline in lab sediment‐water systems. 1. Metabolic fate and partitioning of radioactivity

Abstract

AbstractUsing a standard screening procedure, the fate of [14C]‐4‐nitrophenol and [14C]‐3,4‐dichloroamline was studied in lab sediment‐water systems; incubation intervals ranged from 4 h to 90 d. The sediments were collected from a creek, a pond, and a drainage ditch of a fruit‐growing plantation, and were characterized. Both compounds and their transformation products were sorbed to the sediments in large quantities; radioactivity left in the water phase was below 11 % after termination of the experiments. Besides minor amounts of 14CO2, 3,4‐dichloroaniline was converted to predominantly nonextractable residues, presumably without preceding microbial transformation of the 3,4‐dichloroaniline moiety. Two main end products were observed in the 4‐nitrophenol experiments, namely nonextractable residues and 14CO2. Data obtained from the sediment exhibiting highest microbial activity probably indicated a further mineralization of 4‐nitrophenol‐derived sediment‐bound residues. On the whole, 4‐nitrophenol presumably shows low persistence and accumulation in sediment‐water systems, whereas due to its stability the toxicity of sediment‐sorbed 3,4‐dichloroaniline should be examined.