Among organophosphorothioate (OPT) pesticides, malathion is considered relatively safe for use in mammals. Its rapid degradation by carboxylesterases competes with the cytochrome P450 (P450)-catalyzed formation of malaoxon, the toxic metabolite. However, impurities in commercial formulations are potent inhibitors of carboxylesterase, allowing a dramatic increase in malaoxon formation. Malathion...

Understanding how ecological interactions mitigate the impacts of perturbations such as pesticides in biological communities is an important basic and applied question for ecologists. In aquatic ecosystems, new evidence from microcosm experiments suggests that submerged macrophytes can buffer cladocerans from pulse exposures to the widely used insecticide malathion, and that mitigation increase...

Between September 1995 and September 1996, 4-day composite duplicate plate samples (379 solid food samples and 303 beverage samples) were obtained from a stratified random sample of 75 individuals in Maryland and analyzed for the presence of 10 pesticides. Samples were collected in each of six approximately equally spaced cycles as part of a larger pilot investigation of longitudinal exposure t...

The structure of malathion, S-[1,2-di(ethoxycarbonyl)ethyl] 00-dimethyl phosphorodithioate, has suggested to many investigators (e.g. Murphy & Dubois, 1957; Seume & O'Brien, 1960) that hydrolases may be involved in the synergism observed by Frawley, Fuyat, Hagan, Blake & Fitzhugh (1957) between malathion and O-ethyl O-p-nitrophenyl phenyl phosphorothioate. On the basis of their known substrate ...

Mealybugs (Phenacoccus solenopsis) is a diverstating insect pect of agriculture crops, vegetables, fruits and ornamental plants. In the current study, impact synthetic pesticides (malathion, profenophos, bifenthrin), organic plant extracts (neem, tobacco eucalyptus) natural enemies such as lady bird beetle (Coccinella septempunctata), brumus beetle, (Brumus suturalis), spider (Cheiracanthium me...

An L-glutathione-functionalized silica adsorbent was applied in this study to remove malathion from aqueous media. This has demonstrated an improved adsorption efficiency of malathion. The maximum uptake achieved 130 mg g?1 at pH 8. Equilibrium reached after about 90 min. A pseudo-second-order model best described the kinetics. isotherms were simulated by Freundlich model. functional groups are...

PURPOSE Induction of oxidative stress by Organophosphate compounds (OPs) has been previously reported. In the present work, the mechanism of protective effects of N-acetylcysteine as a glutathion (GSH) prodrug against malathion-induced cell toxicity was investigated. In this work, freshly isolated rat hepatocytes were used to determine the effect of NAC on malathion-induced cytotoxicity, format...

NADPH cytochrome P450 reductase (CPR) is essential for cytochrome P450 catalysis, which is important in the detoxification and activation of xenobiotics. In this study, two transcripts of Bactrocera dorsalis CPR (BdCPR) were cloned, and the deduced amino-acid sequence had an N-terminus membrane anchor for BdCPR-X1 and three conserved binding domains (FMN, FAD, and NADP), as well as an FAD bindi...

Mosquito larvae were collected from the houses of dengue infected patients in Bangkok, Thailand from 55 sites (36 out of the 50 districts of Metropolitan Bangkok). Aedes aegypti larvae were tested against temephos using WHO bioassay techniques. Adult mosquitoes were tested for susceptibility to permethrin, deltamethrin, cyfluthrin, malathion and DDT using WHO diagnostic doses. Most of the larva...