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- Rodriguez, Teresa, et al.
(författare)
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Assessment of long-term and recent pesticide exposure among rural school children in Nicaragua
- 2012
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Ingår i: Occupational and Environmental Medicine. - : BMJ. - 1351-0711 .- 1470-7926. ; 69:2, s. 119-125
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Tidskriftsartikel (refereegranskat)abstract
- Objective This study assessed pesticide exposure of children in rural Nicaragua in relation to parental pesticide use, from around conception to current school age, as part of an epidemiological evaluation of neurodevelopment effects. Methods We included 132 children whose parents were subsistence farmers or plantation workers, or had an agricultural history. As proxies for children's long-term exposures, we constructed cumulative parental pesticide-specific use indices for periods before and after the child's birth from data obtained using an icon-calendar-based questionnaire, of application hours (h) for plantation workers and subsistence farmers, and of kilograms of active ingredients (ai) only for subsistence farmers. Pesticide residues of TCPY, 3-PBA and 2,4-D were analysed in children's urine as indicators for current exposures. Results Life-time indices were highest for the organophosphates chlorpyrifos (median 114 h (min 2; max 1584), 19.2 kg ai (min 0.37; max 548)) and methamidophos (84 h (6; 1964), 12.2 kg ai (0.30; 780)). The P50 values of children's urinary residues were 3.7 mu g/g creatinine for TCPY, 2.8 for 3-PBA and 0.9 for 2,4-D; TCPY values are comparable with those in other countries, but 3-PBA and 2,4-D are considerably higher. The maximum levels for all three pesticides are the highest reported for children. Residues increased on days after application, but most high residue levels were unrelated to parental pesticide applications. Conclusion Urinary pesticide residues reveal high environmental exposure among children in rural Nicaragua. The quantitative parental pesticide use indices as proxies for children's exposures during different periods may be useful for the evaluation of developmental health effects.
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| 2. |
- Rodriguez, Teresa, 1966-, et al.
(författare)
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Cognitive deficits in organophosphate exposed children of Nicaraguan subsistence farmers
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Objective: This study examined cognitive and behavioral performance among school-age children in Nicaragua in relation with long-term and recent organophosphate exposures.Methods: Long-term organophosphate was assessed in 110 children aged 7-9 through a parental use index of kg of organophosphate during de pregnancy, first year of life and from 1 year old to the present. Recent exposure was determined in a subset of 74 children by urinary 3,5,6-trichloro-2-pyridinol (TCPY) levels. Cognitive function was evaluated with Wechsler Intelligence Scale for Children (WISC IV), total IQ and subtests grouped into indices for perceptual reasoning, verbal comprehension, working memory, and processing speed. Behavior at school was measured with the Conners’ Teacher Rating Scale-Revised:Short (CTRS-R:S). Multivariate linear regression models assessed adjusted associations.Results: For each 10-fold increase in prenatal indices for total OP use, children’s performance on working memory significantly decreased with 3.5 points, and similarly for chlorpyrifos and methamidophos. Prenatal methamidophos use was, in addition, significantly associated with poorer verbal comprehension and decrease in total IQ, a 10-fold use increase decreasing scores with 3.8 and 3.3 points respectively. Urinary TCPY (mg/g of creatinine) also affected, not significantly, working memory with a 3.2 point decrease for each 10-fold increase. This study did not find associations between postnatal organophosphate use indices and cognitive performance, or pre or postnatal use indices with behavior. Conclusion: Prenatal exposure to organophosphates decreased the cognitive abilities in Nicaraguan children, particularly in working memory. Methamidophos was also associated with poor verbal comprehension and total IQ.
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