TITLE:
Evaluation of the Genotoxicity of Chlorpyrifos in Common Indus Valley Toad, Bufo stomaticus Using Alkaline Single-Cell Gel Electrophoresis (Comet) Assay
AUTHORS:
Muhammad Ismail, Qaiser Mahmood Khan, Rahat Ali, Tayyaba Ali, Ameena Mobeen
KEYWORDS:
Pesticide; Chlorpyrifos; Tadpoles; DNA Damage; Comet Assay
JOURNAL NAME:
Agricultural Sciences,
Vol.5 No.4,
March
26,
2014
ABSTRACT: Chlorpyrifos
is a commonly used pesticide of organophosphate group, which causes
toxicological effects in non-target
organisms especially fish and frogs. In the present study, the genotoxicity of
sublethal concentrations of chlorpyrifos was observed in the erythrocytes of
common Indus valley toad, Bufo stomaticus,
using the Alkaline Single-Cell Gel Electrophoresis (Comet) assay. In the first
step, acute toxicity of chlorpyrifos was evaluated by exposing the tadpoles to
high concentrations of the pesticide. The acute LC50 value of
chlorpyrifos, calculated by Trimmed Spearman-Karber (TSK) in static bioassay,
was found to be 930.0 μg/L.
On the basis of acute LC50 value, the tadpoles were exposed to three
sublethal concentrations (155, 233 and 465 μg/L) of chlorpyrifos for 96 h. Blood cells were
collected at every 24 h
interval and were subjected to the Alkaline Single-Cell Gel Electrophoresis
assay. The observed DNA damage was concentration and time-dependent, and those levels of DNA
damage in between the tested concentrations and times were significantly different
(p Bufo stomaticus.