Exposures of preschool children to chlorpyrifos, diazinon, pentachlorophenol, and 2,4-dichlorophenoxyacetic acid over 3 years from 2003 to 2005: A longitudinal model

Abstract

The impact of the US EPA-required phase-outs starting in 2000-2001 of residential uses of the organophosphate (OP) pesticides chlorpyrifos (CPF) and diazinon (DZN) on preschool children's pesticide exposures was investigated over 2003-2005, in the Raleigh-Durham-Chapel Hill area of North Carolina. Data were collected from 50 homes, each with a child initially of age 3 years (OCh) and a younger child (YCh). Environmental samples (indoor and outdoor air, dust, soil) and child-specific samples (hand surface residue, urine, diet) were collected annually over 24-h periods at each home. Child time-activity diaries and household pesticide use information were also collected. Analytes included CPF and DZN; pentachlorophenol (PCP); 2,4-dichlorophenoxyacetic acid (2,4-D); the CPF metabolite 3,5,6-trichloro-2-pyridinol (TCP); and the DZN metabolite 2-isopropyl-6-methyl-4-pyrimidinol (IMP). Exposures (ng/day) through the inhalation, dietary ingestion, and indirect ingestion were calculated. Aggregate potential doses in ng/kg body weight per day (ng/kg/day) were obtained by summing the potential doses through the three routes of exposure. Geometric mean aggregate potential doses decreased from 2003 to 2005 for both OCh and YCh, with the exception of 2,4-D. Child-specific longitudinal modeling indicated significant declines across time of the potential doses of CPF, DZN, and PCP for both children; declines of IMP for both children, significant only for OCh; a decline of TCP for OCh but an increase of TCP for YCh; and no significant change of 2,4-D for either child. Age-adjusted modeling indicated significant effects of the child's age for all except CPF, and of time for all except PCP and 2,4-D. Within-home variability was small compared with that between homes; variability was smallest for 2,4-D, both within and between homes. The aggregate potential doses of CPF and DZN were well below published reference dose values. These findings show the success of the US EPA restrictions in reducing young children's pesticide exposures.

Predictors of urinary levels of 2,4-dichlorophenoxyacetic acid, 3,5,6-trichloro-2-pyridinol, 3-phenoxybenzoic acid, and pentachlorophenol in 121 adults in Ohio

“…Sweet and salty snacks were defined as highly processed food items like pretzels, popcorn, potato chips, rice cakes, crackers, cookies, and cereal/granola bars. Dietary ingestion is considered a major exposure route of 2,4-D in the general population in the US (Nishioka et al, 2001;Morgan et al, 2004;Wilson et al, 2010). However, scant data are available on the specific foods consumed by adults that contain 2,4-D residues (US FDA, 2014).…”

“…E-mail address: morgan.marsha@epa.gov soil, and/or wipes collected at US residences (Colt et al, 2004;Stout et al, 2009;Wilson et al, 2010;Morgan et al, 2014;Trunnelle et al, 2014). In addition, studies across the US have reported measureable concentrations of several different pesticide biomarkers including 2,4-dichlorophenoxyacetic acid (2,4-D), 3,5,6-trichloro-2-pyridinol (TCP), 3-phenoxybenzoic acid (3-PBA), and pentachlorophenol (PCP) in the urine of the general adult population (Berkowitz et al, 2003;Barr et al, 2005a;Meeker et al, 2005;Morgan et al, 2008a;CDC, 2009;Barr et al, 2010;McKelvey et al, 2013;Trunnelle et al, 2014) (Fig.…”

Multiresidue analysis of organophosphate and pyrethroid pesticides in duplicate-diet solid food by pressurized liquid extraction

“…[9,10] Exposures to OPP and PYR could occur through inhalation, dermal absorption, or ingestion, with dietary ingestion generally found to be the major route of exposure. [3][4][5]11,12] OPP and PYR present in the diet may result from treatment of crops during the growing season and during storage, treatment of animals against insect-borne diseases, and/or contamination during food preparation.…”

Assessing exposure of young children to common endocrine-disrupting chemicals in the home environment: a review and commentary of the questionnaire-based approach

“…Naeher et al reported the association between selfreported insecticide use and exposure to both pyrethroids and organophosphates in the US and found a significant association only for pyrethroids (69). It is likely that the association between domestic insecticide use and pyrethroid exposure from studies in the US is more consistent than the association with organophosphate exposure; this is because the use of pyrethroid active ingredients in domestic insecticides has increased due to the the implementation of stricter regulations on the sale of organophosphates for domestic use (76).…”