Despite increasing awareness of the potentially harmful effects of pesticides — volatile organic compounds, parabens and DEHP — on human health, these chemicals can still be found in consumer goods. Another example are organophosphates (OP), which are often used in insecticides, flea collars and pet shampoos. Severe OP poisoning can result in seizures and death; even limited exposure has been linked to significant developmental delays in children.

A 2012 study published in Environmental Health Perspectives, “Associations of Prenatal Exposure to Organophosphate Pesticide Metabolites with Gestational Age and Birthweight,” used data from 344 mother/child pairings in Cincinnati to measure the relationship between a child’s levels of prenatal OP pesticide exposure and her gestational age and birthweight. Study participants were adult women with household incomes between $55,000 and $85,000; the majority of participants were white (62%), married (68%) and between the ages of 25 and 35 (60%). The study was a joint effort by researchers at Emory University, Harvard University, Simon Fraser University, the Centers for Disease Control and Prevention, BC Children’s Hospital in Vancouver and Cincinnati Children’s Hospital Medical Center.

Key study findings include:

• “Prenatal urinary DAP [Dialkyl Phosphate] concentrations were associated with shortened gestation and reduced birthweight in this cohort, but the effects differed by race/ethnicity and … genotypes.”
• A 10-fold increase in OP pesticide concentrations in the mother was associated with a 0.5 week decrease in the infant’s gestational age. The same increase in maternal prenatal OP pesticide exposure is associated with a decline in birthweight of 151 grams (adjusted to account for changes in gestational age): “We found that maternal exposure to OP insecticides … was inversely associated with gestational age and birthweight.”
• The relationship between OP pesticide concentrations and gestational age was stronger for white newborns (-0.7 weeks) than for black newborns (-0.1 weeks). The authors note that “maternal race/ethnicity may also be acting as a proxy for a combination of conditions — socioeconomic factors, genetic susceptibility, psychological stressors, and environmental toxicants — only some of which were measured in our study.”
• “Diet and home pesticide use have been identified as important routes of exposure in non-agricultural populations, although [an earlier study] found that switching children from conventional to organic diets for several days reduced urinary OP metabolites to levels near or below the limit of detection, suggesting that diet was the primary source of exposure in that study population.”

The study’s authors conclude that “although their use in the United States has declined in recent years, exposures to organophosphate insecticides remain widespread.”

Tags: children, consumer affairs, pollution, parenting