Ameliorating acidic soils is a common practice and may affect the bioavailability of an ionizable organic pollutant to organisms. The toxicity of the weak base carbendazim to the earthworm (Eisenia fetida) was studied in an acidic soil (pH-H2O, 4.6) and in the ameliorated soil (pH-H2O, 7.5). The results indicated that the median lethal concentration of carbendazim for E. fetida decreased from 21.8mg/kg in acidic soil to 7.35mg/kg in the ameliorated soil. To understand why the amelioration increased carbendazim toxicity to the earthworm, the aut...
