Effect of RPR-V, a thiol Derivative of monocrotophos on housefly acetylcholinesterase. Journal of Ecotoxicology and Environmental Monitoring 8, 29–36 (1998) (original) (raw)
Related papers
Effect of RPR-V, a thiol Derivative of monocrotophos on housefly acetylcholinesterase.
Journal of Ecotoxicology and Environmental Monitoring 8, 29–36 (1998)
Insc£ticidal studies of monocrotophos (MCP) and its newly synthesized thiol analogue RPR-V were: died on housefly MIl!JCQ domestica Linnaeus (Diptera:Muscidae). RPR-V exhibited high insecticidal acitivity with LD 50 ofO.0747Jlglinsect when compared to MCP, which is leis active with LD 50 0fO.093J.lg1 insect. The study on inhibition of housefly head acctylcholincscsterasc (AChE) activity indicated in vitro neurotoxic potentialitity of these two organophosphorus pesticides. MCP and RPR-V have shown competitive inhibition on AChE and altered the K,. values widely in a dose dependent manner.~on the K 1 values, RPR-V wns found to be more active than MCP.
ixing organophosphate and pyrethroid becomes very common in the insecticide markets in the developing countries and result in an increase in the prevalence of mixed toxicity. The present study aimed to evaluate the toxic effects of a commercial preparation of a pesticide mixture Durasin, which contains 60 % diazinon (DA) and 0.5% deltamethrin (DM), compared to the individual commercial pesticides of 30% DA and 5% DM. Cholinesterase (ChE), malonaldehyde (MDA), glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase (SOD), total cholesterol (TC), triglyceride (TG) and non-specific esterase's isoenzymes in blood of male albino rats were determined after 7 and 14 days of treatment. The weekly recorded biochemical results were used as criteria for estimating the joint action of the tested pesticide mixture. Antioxidant defense mechanism and lipid peroxidation in rat plasma displayed the same responses with different intensity depending on the different treatments. Biochemical analysis showed that administration of DA and DM caused alterations in lipid metabolism and non-specific esterase. The results also revealed that the mixture induced antagonistic effects toward all the tested parameters except the total reduced glutathione level, which was synergetic at the 2 nd week. The study pointed out to the importance of performing biochemical tests on the commercial mixture of insecticides.
Comparative study on pesticide mixture of organophosphorus and pyrethroid in commercial formulation
Environmental Toxicology and Pharmacology, 2009
ixing organophosphate and pyrethroid becomes very common in the insecticide markets in the developing countries and result in an increase in the prevalence of mixed toxicity. The present study aimed to evaluate the toxic effects of a commercial preparation of a pesticide mixture Durasin, which contains 60 % diazinon (DA) and 0.5% deltamethrin (DM), compared to the individual commercial pesticides of 30% DA and 5% DM. Cholinesterase (ChE), malonaldehyde (MDA), glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase (SOD), total cholesterol (TC), triglyceride (TG) and non-specific esterase's isoenzymes in blood of male albino rats were determined after 7 and 14 days of treatment. The weekly recorded biochemical results were used as criteria for estimating the joint action of the tested pesticide mixture. Antioxidant defense mechanism and lipid peroxidation in rat plasma displayed the same responses with different intensity depending on the different treatments. Biochemical analysis showed that administration of DA and DM caused alterations in lipid metabolism and non-specific esterase. The results also revealed that the mixture induced antagonistic effects toward all the tested parameters except the total reduced glutathione level, which was synergetic at the 2 nd week. The study pointed out to the importance of performing biochemical tests on the commercial mixture of insecticides.
2003
Structure-toxicity relationships were studied for a set of 67 insecticides by means of multiple linear regression (MLR). The values of log LD50 (lethal dose 50, oral, rat) of the studied compounds were well correlated with the descriptors encoding the chemical structures. Considering the pertinent descriptors, a correlation coefficient of 0.87 (s = 0.42, n = 67) was obtained for the MLR model. The present study suggests a quantitative interpretation of the structure-toxicity relationships which otherwise cannot be explained within the framework of the insecticides. This information is pertinent to the further design of new insecticides.
TOXICOLOGICAL STUDIES OF SOME PESTICIDES IN RELATION TO THEIR SIDE EFFECTS
The study aimed to evaluate the insecticidal activity of eight organophosphate and carbamate insecticides against certain pests commonly attacking vegetable plants. The pests included sucking pests (i. e. aphids, whitefly, mites) and the cotton leafworm Spodoptera littoralis. In this respect laboratory and field experiments (at fields grown with squash and okra) were carried out. In addition, the toxicity these pesticides to the predator, paederus alferii in the laboratory was studied. The tested organophosphorus were chloropyrifos-methyl, dimethoate, phenthoate, profenofos and pirimiphos-methyl while those of carbamates were, carbosulfan, primicarb and propoxur. The most efficient insecticides (i. e. chloropyrifos-methyl and pirimicarb) were further evaluated for their mammalian toxicity against white albino rats. So, acute and subchronic studies were conducted. In subchronic studies rats were orally given the insecticides at doses 1/ 10 and 1/30 LD50 for each insecticide. The treatmen...
Mechanistic Approach for the Chemical and Bio-Chemical Aspects of Organophosphate Pesticides
international journal of chemical sciences, 2013
Organophosphate pesticides are the ester forms of phosphoric acid usually considered as secure for agriculture uses due to their relatively fast degradation rates. Organophosphorus pesticides have been extensively used in the area of agriculture to manage insect or pests of a number of economically important crops. Organophosphate pesticides are well-known as the inhibitor of acetylcholinesterase activity, not in insects only, but can also affect the nervous system of other organisms as well as humans. Organophosphorus pesticides are not restricted to anticholinesterase action, but comprise genotoxicity and teratogenicity. Such severe health consequences signify a requirement for a better understanding of the fate of organophosphates in the environment. The safe and effective use of pesticides requires knowledge of their mode of action in pests and adverse effects in non-target organisms coupled with an understanding of their metabolic activation and detoxification. Keeping all thes...
Environmental Toxicology and Chemistry, 2007
A large number of organophosphorous insecticides (OPs) are chiral compounds, and yet enantioselectivity in their environmental fate and effects is rarely addressed. In the present study, we isolated individual enantiomers of three OPs, profenofos, fonofos, and crotoxyphos, and evaluated enantioselectivity in their inhibition of acetylcholinesterase (AChE). Acetylcholinesterase inhibition by the enantiomers and racemates was determined in vivo in the aquatic invertebrate Daphnia magna and in Japanese medaka (Oryzias latipes) as well as in vitro with electric eel (Electrophorus electricus) and human recombinant AChEs. The overall results showed variable sensitivity between AChE enzymes from different species as well as variable magnitude of enantioselectivity in enzyme inhibition. The (Ϫ)-enantiomer of profenofos was 4.3-to 8.5-fold more inhibitory to AChE in vivo, whereas (Ϫ)-fonofos was 2.3-to 29-fold more potent than the corresponding (ϩ)-enantiomer. The (ϩ)-enantiomer of crotoxyphos was 1.1-to 11-fold more inhibitory to AChE than the (Ϫ)-enantiomer. In contrast, the in vitro results showed (ϩ)-profenofos to be 2.6-to 71.8-fold more inhibitory than the (Ϫ)-enantiomer and (Ϫ)-crotoxyphos to be 1.6-to 1.9-fold more active than the (ϩ)-enantiomer. The reversed direction of enantioselectivity observed between the in vivo and in vitro assays suggests enantioselectivity within toxicodynamic processes such as uptake, biotransformation, or elimination. Findings from the present study provide evidence of enantioselectivity in the AChE inhibition of chiral OPs in nontarget organisms and indicate the need to consider enantiomers individually when assessing environmental risk of these chiral pesticides.
Poisoning with organophosphorus insecticides
Canadian Medical Association journal, 1965
Because of an increasing incidence of poisoning with the newer organophosphorus anticholinesterase insecticides, these compounds have been reviewed in terms of their history and pharmacology, relationship with other drugs, factors affecting toxicity, mechanism of action, toxic signs and treatment. The modern organophosphorus pesticide requires metabolic conversion before toxicity develops. Insects have a greater propensity for this conversion than humans. Nevertheless, this conversion does occur in humans and can be potentiated by other drugs. Toxicity also varies with age, sex, route and frequency of administration, and previous exposure. The mechanism of toxicity is inhibition of acetylcholinesterase, causing an intoxicating build-up of acetylcholine. Signs and symptoms consist of the clinical manifestations of unopposed parasympathetic and central activity. Treatment must be initiated early. Respiration must be maintained and the effects of acetylcholine must be counteracted by m...
Investigation of the toxicity of some organophosphorus pesticides in a repeated dose study in rats
Romanian journal of morphology and embryology = Revue roumaine de morphologie et embryologie, 2013
The study aimed to the investigation of the toxicity of organophosphorus pesticides malathion (MLT) and diazinon (DZN) in Wistar rats in a repeated dose study for 35 days. MLT and DZN in corn oil vehicle were oral administered. Body and organs weights, plasma and brain cholinesterase activities, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, histopathological changes in liver and kidney, and some parameters of the immune function, such as leukocyte formula, spleen weight and cellularity, spleen lymphocytes proliferation in response to concanavalin A (Con A) were investigated; the potential oxidative stress (malondialdehyde in plasma and brain, and blood catalase activity) was also evaluated. No clinical toxicity signs attributed to pesticides were noted; no significant changes in the organ weights have been found. Body weight tends slightly to increase, predominantly in DZN treated rats. The results suggest that plasma cholinesterase is more su...