Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this study was to characterize worker exposure to azinphos-methyl (Guthion) over an entire 4-6 week apple-thinning season. Twenty workers from three work sites in the Chelan-Douglas County region of Washington state were recruited for the study. Exposure potential was estimated by dislodgeable foliar residue measurements, and individual exposures were estimated by biological monitoring through urinary metabolites. Measureable azinphos-methyl residues were found on apple foliage at all sites throughout the six-week sampling period, indicating continuous exposure potential (median residue level of 0.5 microgram/cm2). Measurable levels of the urinary dialkylphosphate metabolite, DMTP, were found in virtually all urine samples (limit of detection = 0.04 microgram/mL). Mean DMTP concentrations differed significantly across sites (0.53, 0.29, and 0.90 microgram/mL for Sites 1-3, respectively; analysis of variance, p < .002), and intraindividual variability was much greater than interindividual differences. Group mean DMTP concentrations at each site fluctuated according to foliar residue levels. Measurable DMTP concentrations were found in 9% of reference workers, ranging from 0.04-0.18 microgram/mL. Cholinesterase activity levels monitored with a field test kit were not considered reliable due to temperature changes of the instrument.
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PMID:Farmworker exposure to organophosphorus pesticide residues during apple thinning in central Washington State. 1063 41

The results of biological monitoring by assay of urinary 3,5,6-trichloro-2-pyridinol and alkylphosphates (DMP, DMTP) in groups of 9 and 2 workers exposed to chlorpyrifos-methyl during vine spraying and manual leaf thinning 5-11 d after spraying, respectively, are reported. The results are compared with those of a control group of 46 subjects not occupationally exposed to organophosphate insecticides. Significantly higher urinary excretion of metabolites (Mann-Whitney U-test) was found in both groups than in controls. Levels of 3,5,6-trichloro-2-pyridinol (mean +/- SD) were 15.9 + 10.6 nmol/g creatinine (n = 33) for controls, 92.4 + 162.5 nmol/g creatinine (n = 20) for manual workers, and 675.5 + 1110.8 nmol/g creatinine (n = 48) for workers spraying and mixing the insecticide. Levels of DMP (mean +/- SD) were 63.8 + 100.1 nmol/g creatinine (n = 42), 123.0 + 79.0 nmol/g creatinine (n = 20), and 577.2 + 1003.2 nmol/g creatinine (n = 61), respectively, for the same 3 groups. Levels of DMTP (mean +/- SD) were 153.4 + 164.4 nmol/g creatinine (n = 43), 489.3 + 288.3 nmol/g creatinine (n = 20), and 297.6 + 215.4 nmol/g creatinine (n = 61), respectively, for the same 3 groups. Good correlations were found between urinary excretion of 3,5,6-trichloro-2-pyridinol and DMP (r = .776 for manual workers; r = .775 for workers mixing and spraying the insecticide) or DMTP (r = .558 and r = .746, respectively for the same 2 groups). The peak of excretion of the three metabolites was found in urine samples collected the night after the spraying or leaf thinning operations.
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PMID:Biological monitoring of exposure to chlorpyrifos-methyl by assay of urinary alkylphosphates and 3,5,6-trichloro-2-pyridinol. 1527 31