Children's exposure to chlorpyrifos and parathion in an agricultural community in central Washington State.

Abstract

We measured two diethyl organophosphorus (OP) pesticides--chlorpyrifos and parathion--in residences, and their metabolic by-products, in the urine of children 6 years old or younger in a central Washington State agricultural community. Exposures to two dimethyl OP pesticides (azinphos-methyl and phosmet) in this same population have been reported previously. We categorized children by parental occupation and by household proximity to pesticide-treated farmland. Median chlorpyrifos house dust concentrations were highest for the 49 applicator homes (0.4 microg/g), followed by the 12 farm-worker homes (0.3 microg/g) and the 14 nonagricultural reference homes (0.1 microg/g), and were statistically different (p < 0.001); we observed a similar pattern for parathion in house dust. Chlorpyrifos was measurable in the house dust of all homes, whereas we found parathion in only 41% of the homes. Twenty-four percent of the urine samples from study children had measurable 3,5,6-trichloro-2-pyridinol (TCPy) concentrations [limits of quantitation (LOQ) = 8 microg/L], and 7% had measurable 4-nitrophenol concentrations (LOQ = 9 microg/L). Child urinary metabolite concentrations did not differ across parental occupational classifications. Homes in close proximity (200 ft/60 m) to pesticide-treated farmland had higher chlorpyrifos (p = 0.01) and parathion (p = 0.014) house dust concentrations than did homes farther away, but this effect was not reflected in the urinary metabolite data. Use of OP pesticides in the garden was associated with an increase in TCPy concentrations in children's urine. Parathion concentrations in house dust decreased 10-fold from 1992 to 1995, consistent with the discontinued use of this product in the region in the early 1990s.

Aggregate exposures of nine preschool children to persistent organic pollutants at day care and at home

“…A recent longitudinal study of the urinary OP metabolite levels of children living in an area where OP pesticides are used in agriculture found that the metabolite concentrations were higher in months when OPs were used on orchards, despite no direct contact of family members with the pesticides or location near the sprayed orchards (Koch et al, 2002). In a study of CPF levels in house dust compared to urinary TCP levels for children of pesticide applicators, farm workers, and nonagricultural workers, urinary TCP did not match well the parental occupation, although it did match home garden pesticide use (Fenske et al, 2000(Fenske et al, , 2002b. Observed levels of TCP may not match well the potential intake of CPF in nonacute exposure settings.…”

Characterization of chlorpyrifos-induced apoptosis in placental cells

“…CPF and its metabolites have been detected in farm animals, such as cattle, hogs and sheep (Ivey 1979;Ivey and Palmer 1979;Ivey and Palmer 1981). Moreover, chlorpyrifos residues or its metabolites have been discovered in the diet of preschoolers (Fenske et al 2002a), in the urine of children living in proximity to orchards (Lu et al 2000;Fenske et al 2002b), as well as in the cord blood of infants born to minority women living in urban settings (Whyatt et al 2004). …”

Expressing urine from a gel disposable diaper for biomonitoring using phthalates as an example

“…Indoor concentrations of pesticides in proximity to pesticidetreated farmland have been measured (Fenske et al, 2002). For example, it has been shown that pesticide exposure in children could potentially be increased if they live in homes in close proximity (60 m) to pesticide-treated farmland (Fenske et al, 2002).…”

“…For example, it has been shown that pesticide exposure in children could potentially be increased if they live in homes in close proximity (60 m) to pesticide-treated farmland (Fenske et al, 2002). Clothing and cars of farm workers can also be a source of pesticide exposures for children.…”