A consistent correlation between elevated esterase activity and methyl parathion resistance among Nebraska western corn rootworm, Diabrotica virgifera virgifera LeConte, populations has previously been documented. Characterization of general esterase activity using naphtholic esters as model substrates indicated that differences between resistant and susceptible strains could be maximized by op...

This work illustrates the toxicological impact of pesticide methyl parathion (MP) (dust—2 % active ingredient, a.i.) on growth and reproduction performance in tropical earthworms: Metaphire posthuma (endogeic), Lampito mauritii (anecic) and Allolobophora parva (epigeic). A total of three concentrations (a.i. g kg dry test soil), 1.00 (T1), 1.125 (T2) and 2.25 (T3) of MP, were applied in test su...

The western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a major pest of cultivated corn in North America and has recently begun to invade Europe. In addition to crop rotation, chemical control is an important option for D. v. virgifera management. However, resistance to chemical insecticides has evolved repeatedly in the USA. In Europe, chemical control...

Pseudomonas diminuta, P. putida and P. aeruginosa were established as a biodegrading agent for Methyl Parathion (MP) at 1200 mg/L, under basic growth parameters for mesophiles. In this study, the effects of process parameters, such as temperature, pH, salinity, carbon and nitrogen sources on the growth of those bacteria were studied and optimized to establish higher degradation of the target ch...

The objective of this study was to assess insecticide resistance in anopheline mosquito populations in agroecosystems with high and low insecticide use in a malaria endemic area in Chiang Mai province in northern Thailand. Anopheline mosquitoes were collected in May and June 2004 from two locations with different agricultural insecticide intensity (HIGH and LOW), but similar in vector control s...

Pesticides may contribute to respiratory symptoms among farmers. Using the Agricultural Health Study, a large cohort of certified pesticide applicators in Iowa and North Carolina, we explored the association between wheeze and pesticide use in the past year. Self-administered questionnaires contained items on 40 currently used pesticides and pesticide application practices. A total of 20,468 ap...

We have developed an optical chemical sensor for the detection of organophosphate (OP) compounds using a polymerized crystalline colloidal array (PCCA) thin film composed of a close-packed colloidal array of polystyrene particles. The PCCA thin film was modified with β-cyclodextrin (β-CD) polymer as a capping cavity for the selective detection of paraoxon-ethyl and parathion-ethyl chemical agen...

We previously demonstrated that the organophosphorus (OP) insecticide chlorpyrifos potentiates vagally induced bronchoconstriction independent of acetylcholinesterase (AChE) inhibition by decreasing the function of neuronal M2 muscarinic receptors that normally inhibit acetylcholine release from parasympathetic nerves supplying airway smooth muscle. However, it has been reported that different ...

The rate and extent of dermal absorption are important in the analysis of risk from dermal exposure to toxic chemicals and for the development of topically applied drugs, barriers, insect repellents, and cosmetics. In vitro flow-through cells offer a convenient method for the study of dermal absorption that is relevant to the initial processes of dermal absorption. This study describes a physio...