Accumulation and elimination kinetics of herbicides butachlor, thiobencarb and chlomethoxyfen by Aristichthys nobilis
Journal
Pesticide Science
Journal Volume
49
Journal Volume
49
Journal Issue
2
Journal Issue
2
Pages
178-184
Start Page
178
End Page
184
ISSN
0031613X
Date Issued
1997
Author(s)
Abstract
Bioconcentration kinetics of three major paddy-field herbicides, butachlor, thiobencarb and chlomethoxyfen were investigated by accumulation and elimination measurements in laboratory experiments with black silver carp (Aristichthys nobilis). The biological half-lives of the three herbicides on exposure at high and low concentrations were 11.6 and 23.1 days for butachlor, 13.9 and 17.3 days for thiobencarb and 5.6 and 4.5 h for chlomethoxyfen, respectively. One- and two-compartment models were used to elucidate the bioconcentration kinetics. Data from a short-term, 14-day expiry experiment were used to estimate the parameters in the models by non-linear regression analysis, and the bioconcentration factors (BCF) in the steady state were calculated from those parameters. The BCF in the steady state have the descending order thiobencarb > chlomethoxyfen > butachlor at high concentration, and butachlor > thiobencarb > chlomethoxyfen at low concentration. One-compartment model for butachlor and thiobencarb and a two-compartment model for chlomethoxyfen are useful to predict the BCF on prolonged exposure and, further, to assess the influence of these pollutants.
Subjects
accumulation
Aristichthys nobilis
butachlor
chlomethoxyfen
elimination
thiobencarb
Type
journal article