Toxic Effects of Pollutants on the Mineralization of Chloroform in River Sediments
Toxische effecten van vervuiling op de mineralisatie van chloroform in rivier sedimenten
van Beelen P, van Vlaardingen PLA, Fleuren Kemila AK, van Mil GHAM, van den Berg S
RIVM Report 714206002
The formation of 14C labelled carbon dioxide from 3 mug/l labelled chloroform was studied in anaerobic Dutch river sediments. The observed first order mineralization kinetics showed half-lives of 2-37 days at 20 degr. C in 12 muddy sediments. In contrast most of the sandy sediment samples did not show a mineralization of chloroform when incubated under anaerobic conditions. The concentration giving 10% inhibition of the chloroform mineralization rate (IC10), was derived from these dose effect curves. The IC10 values of added cadmium, chloropyrifos, benzene or mercury were 1400, 1300, 120 and 100 mg/kg dry sediment respectively. The IC10 of added pentachlorophenol was 150 mg/kg in one and 12 mg/kg in another sample. The IC10 of added zinc was 700 mg/kg in one sample and 11 mg/kg in another sample of sediments both containing a background concentration of 800 mg Zn/kg.