Publications by authors named "Banjong Vitayavirasak"

There has been increasing concern in regards to organophosphate (OP) pesticide exposure among farm workers and their families in Thailand's agricultural areas. Therefore, the development of an analytical method for estimating OP pesticide exposure is necessary to allow for monitoring of OP pesticide exposures within these populations. This paper describes an analytical method developed to measure dialkylphosphate (DAP) metabolites in urine.

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Organophosphate pesticide exposures of preschool children in a Thailand agricultural community and reference children living outside the farm area in the same subdistrict were determined. Levels of dialkylphosphate (DAP) metabolites were measured in first-morning-void urine samples. During the dry season (April-May), the farm children excreted significantly higher levels of all DAP metabolites than the reference children did (Mann-Whitney U test, p < 0.

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Risk behavior and environmental sources of exposure to arsenic for 10-year-old schoolchildren were studied in a high exposure area and a low exposure area of Ron Phibun Subdistrict, Ron Phibun District, Nakhon Si Thammarat Province and compared to those in a control area. Arsenic concentrations of surface soil, ambient air and drinking water to which subjects in the high exposure group, the low exposure group and the control group were exposed, were significantly different (p < 0.05).

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A variety of compounds including classical anthelmintics and avermectin analogs were screened for their effects on movements of adult heartworms (HW) (Dirofilaria immitis). Contractile activity was measured by tension recording of spontaneous movements of intact HW coil preparations (6 min compound exposure) and motility was evaluated by observation of spontaneous, free movements in culture (3 and 7 days compound exposure). Results for female HW indicated that some compounds caused spastic paralysis of contractile activity and inhibition of motility in culture (bephenium, DL-tetramisole, and pyrantel); some caused only spastic paralysis of contractile activity (methyridine and disophenol); and some caused only inhibition of motility in culture (chlorpromazine, dithiazanine, 1-ethoxycarbonylmethyl-1-methylpyrrolidinium, and 4-methyltropolone).

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