ABSTRACT
Cypermethrin is a synthetic pyrethroid insecticide used to control pests in domestic, industrial and agricultural situations. This study was carried out to investigate acute oral toxicity and histopathological changes of cypermethrin in albino rats. As per Finney's probit analysis method, at 48 h, LD50 value of cypermethrin in rats was found to be 205 mg/kg bw by gavage method. Behavioural changes were mostly in the form of motor signs. On exposure to sublethal doses (41 mg/kg bw) of cypermethrin as single dose, double dose and multiple dose, mild to severe histological changes in duodenum, lungs and tes-tes could be demonstrated by haematoxylin and eosin staining.
ABSTRACT
Cypermethrin is a synthetic pyrethroid insecticide that has high insecticidal activity, low avian and mammalian toxicity, and adequate stability in air and light. This paper is an attempt to study its toxicity in vivo in rat liver at cellular level. Following exposure to oral, sublethal doses (41 mg/kg bw) of cypermethrin as single dose, double dose and multiple dose with 48 h interval, the histochemical changes were studied in different groups of rat livers. Histochemical examination indicated depletion of polysaccharides in the liver. This change occurred in a dose and timedependent manner in treated rat liver.
ABSTRACT
This study reveals significant variations in dehydrogenase enzymes on administration of oral, sublethal (41mg/kg) doses of cypermethrin as single, double and multiple doses with 48hr intervals. Glucose-6-phosphate dehydrogenase (G-6-PDH) and lactate dehydrogenase (LDH) activities were increased, whereas succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) activities were significantly decreased in muscle and heart tissues of albino rats, in a dose and time dependent manner. G-6-PDH is a key enzyme of HMP pathway. This pathway serves to generate glycolytic intermediates for the production of energy to tolerate toxic stress. SDH is a vital enzyme of citric acid cycle, and catalyses the reversible oxidation of succinate to fumarate. LDH activity shows an increase during anaerobic conditions to meet the energy demands. MDH activity depends on fluctuations of oxidative metabolism, and also reflects the turnover of carbohydrates and energy output.
ABSTRACT
Cypermethrin is a synthetic pyrethroid insecticide with low mammalian toxicity but high insecticidal activity. Following exposure to sublethal concentration of cypermethrin (1/10 LC50 1.63mg/l) in frogs, the haematological profiles were investigated over 7 days and 30 days. The results revealed statistically significant decrease of red blood cells, haemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, and neutrophils, and increase of the other white blood cells, including lymphocytes, monocytes, and eosinophils.
ABSTRACT
Cypermethrin is the most widely used Type II pyrethroid pesticide in India because of its high efficacy against target species, and its reportedly low mammalian toxicity. It is a fast-acting neurotoxin and is known to cause free radical-mediated tissue damage. This paper is an attempt at estimating its toxicity in rats at a molecular level. Following exposure to oral, sublethal doses (41 mg/kg bw) of cypermethrin as single dose, double dose, and multiple dose with 48 h interval, the various profiles of protein metabolism were studied in different groups of rat muscle tissue. Total proteins showed decrement, whereas free amino acids, and the activity of protease, aspartate aminotransferase, alanine aminotransferase and glutamate dehydrogenase as well as ammonia significantly increased in cypermethrin-exposed rats. Urea content increase at all doses of exposure was not statistically significant. These effects on the protein metabolism of rats exposed to cypermethrin, which cause impairment of protein synthetic machinery, indicate its toxic effects on cellular functioning.