Carbaryl-induced behavioural and reproductive abnormalities in the earthworm Metaphire posthuma: a sensitive model.
Carbaryl, an N-methyl carbamate insecticide, is used in India to control foliar insects, but, due to soil contamination, it also adversely affects non-target organisms such as earthworms. This paper deals with the toxic effects of carbaryl on the behavioural and reproductive profiles of the earthworm, Metaphire posthuma. Locomotion and geotaxis were significantly affected, even after a 20-minute exposure to 0.125ppm carbaryl. The hatching of cocoons was altered at 0.5ppm, whereas cocoon production was retarded even at 0.125ppm carbaryl. No cocoon production was observed at 2.0ppm carbaryl. Sperm head abnormalities were reported even at the lowest test concentration of 0.125ppm. Wavy head abnormalities were observed at 0.125ppm carbaryl, whereas at 0.25ppm and 0.5ppm, the sperm heads became amorphous and the head nucleus was turned into granules deposited within the wavy head. It is concluded that the earthworm could be used as an ecosystem model for the initial toxicity testing of environmental pollutants.
Gupta
Shrawan K
SK
Cell Biology Division, Industrial Toxicology Research Centre, P.O. Box 80, M.G. Road, Lucknow 226 001, India.
Saxena
Prem N
PN
D000826:Animal Testing Alternatives; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D012721:Carbaryl / Q000145:classification / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005260:Female; D018466:Gravity Sensing / Q000187:drug effects; D007306:Insecticides / Q000145:classification / Q000633:toxicity*; D008124:Locomotion / Q000187:drug effects; D008297:Male; D009835:Oligochaeta / Q000187:drug effects* / Q000502:physiology; D012098:Reproduction / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects / Q000473:pathology
D007306:Insecticides; D012721:Carbaryl