Effect of temephos on cholinesterase activity in the earthworm Eisenia fetida (Oligochaeta, Lumbricidae).
In this study, adult Eisenia fetida earthworms were exposed to the sub-lethal concentrations of temephos using the contact filter paper test procedure. Since temephos is an organophosphate pesticide, its effects on earthworms were determined by measuring ChE inhibition--a known biomarker of exposure. The ChE activity was measured after a short time of exposure--1 and 2 h. As expected, the lowest ChE activity (72.70% and 38.03% inhibition) was measured at the highest concentration of temephos (120 ng cm(-2)) applied. More interestingly, at the 0.12 ng cm(-2) concentration the ChE activity increased up to 36.28% of activity in the control in all three conducted experiments. Dose-response curves showed an inverted U-shape characteristic for hormesis. This hormetic-like effect could be important for health status of an earthworm.
Hackenberger
Branimir K
BK
Department of Biology, Josip Juraj Strossmayer University, Osijek, Croatia. hack@biologija.unios.hr
Jarić-Perkusić
Davorka
D
Stepić
Sandra
S
D000818:Animals; D001681:Biological Assay; D002800:Cholinesterase Inhibitors / Q000008:administration & dosage / Q000633:toxicity; D002802:Cholinesterases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D007306:Insecticides / Q000633:toxicity*; D009835:Oligochaeta / Q000187:drug effects* / Q000201:enzymology; D012989:Soil Pollutants / Q000633:toxicity; D000002:Temefos / Q000008:administration & dosage / Q000633:toxicity*; D013997:Time Factors
D002800:Cholinesterase Inhibitors; D007306:Insecticides; D012989:Soil Pollutants; D002802:Cholinesterases; D000002:Temefos