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The vector of Chagas disease, Triatoma infestans, is largely controlled by the household application of pyrethroid insecticides. Because effective, large-scale insecticide application is costly and necessitates numerous trained personnel, alternative control techniques are badly needed. We compared the residual effect of organophosphate-based insecticidal paint (Inesfly 5A IGR™ (I5A)) to standard deltamethrin, and a negative control, against T. infestans in a simulated natural environment. We evaluated mortality, knockdown, and ability to take a blood meal among 5 th instar nymphs. I5A paint caused significantly greater mortality at time points up to nine months compared to deltamethrin (Fisher's Exact Test, p < 0.01 in all instances). A year following application, mortality among nymphs in the I5A was similar to those in the deltamethrin (χ2 = 0.76, df=1, p < 0.76). At months 0 and 1 after application, fewer nymphs exposed to deltamethrin took a blood meal compared to insects exposed to paint (Fisher's Exact Tests, p < 0.01 and p < 0.01, respectively). Insecticidal paint may provide an easily-applied means of protection against vectors of Chagas disease. Journal of Vector Ecology 38 (1): 6-11. 2013.

In this study, the changes with respect to time in the serum, brain, liver, kidney and small intestine acetylcholinesterase activities were investigated in both male and female rats administered dichlorvos intraperitoneally (i.p.). For this purpose, 4 mg kg(-1) doses of dichlorvos were injected i.p. in the rats. The control groups, on the other hand, were administered physiological saline via the same route. Rats were killed by decapitation at 0, 2, 4, 8, 16, 32, 64 and 72 hours after administration of dichlorvos and tissues were harvested. Enzyme activities were determined following the necessary treatments. While a significant decrease in enzyme activities in the kidney and small intestine tissues with respect to time were not observed in either sex, a significant decrease in enzyme activities in the serum, as well as in the brain and liver tissues were observed. As a result of our study, acetylcholinesterase activity was found to be decreased compared to controls in both male and female rats from 2 and 4 hours. Enzyme inhibition continued for up to 72 hours.

A procedure is described for the (non-target) screening of hetero-atom-containing compounds in tap and waste water by correlating data obtained by gas chromatography (GC) using atomic emission (AED) and mass selective (MS) detection. Solid-phase extraction (SPE) was coupled on-line to both GC systems to enable the determination of microcontaminants at the 0.02-1 μg L-1 level in 7-50 mL of aqueous sample. The screening was limited to compounds present in at least one heteroatom-selective GC-AED trace above a predetermined concentration level. These compounds were identified by their partial formulae (AED) and the corresponding mass spectra, which were obtained from the CC-MS chromatogram via the retention index concept. The potential of the approach was demonstrated by the identification of target compounds as well as all unknowns present in tap and waste water above the predetermined threshold of 0.05 μg L-1 (tap water) or 0.5 μg L-1 (waste water).