(Beyond Pesticides, March 26, 2010) A new study by researchers at Columbia Universityâ€™s Mailman School of Public Health has linked exposure to the insecticide chlorpyrifos to early childhood developmental delays. Chlorpyrifos is a broad spectrum organophosphate insecticide that was banned for household use in 2001, but is still widely used in agriculture. The study, entitled â€śChlorpyrifos Exposure and Urban Residential Environment Characteristics as Determinants of Early Childhood Neurodevelopment,â€ť was published online and will be published in print in the may issue of the American Journal of Public Health.
The study examined 266 children born between 1998 and 2002 living in low income neighborhoods of the South Bronx and Northern Manhattan in New York City. Before being banned chlorpyrifos was widely used in these areas. Of the children studied, 47% were male, 59% were Dominican and 41% were African American. Researchers compared motor and mental development to levels of exposure to the pesticide at birth. They found that high concentrations of chlorpyrifos in umbilical cord blood (>6.17 pg/g) corresponds to a 6.5 point decrease in the Psychomotor Development Index, and a 3.3 point decrease in the Mental development index in 3 year olds. Previous research published in 2006 on the same study population had controlled for gender, gestational age at birth, ethnicity, maternal education, maternal intelligence quotient, and second hand smoke exposure in utero. This study examined neighborhood characteristics such as poverty levels and dilapidated housing, factors that are also linked to lower test scores. Researchers were able to conclude that neighborhood characteristics and chlorpyrifos exposure were independently associated with childrenâ€™s neurodevelopment.
Chlorpyrifos is the active ingredient in over 800 pesticide productss, and is still very common in the agricultural sector. Chlorpyrifos exposure results from residues on foods, as well as drift from agricultural fields. Young children and developing fetuses are especially susceptible to the effects of pesticide exposure. Study co-author Virginia Rauh, ScD said, â€śWe hope that the results of this study, further demonstrating the neurotoxicity of chlorpyrifos under a range of community conditions, may inform public health professionals and policy-makers about the potential hazards of exposure to this chemical for pregnant women and young children.â€ť Another recent study of mice found low level in utero exposure to chlorpyrifos can have effects such as changes in brain function and altered thyroid levels that last into adulthood.
Exposure to chlorpyrifos can be greatly reduced by eating organic foods, free of pesticide residue. Beyond Pesticides supports organic agriculture as effecting good land stewardship and a reduction in hazardous chemical exposures for workers on the farm.
EPA registration for Chlorpyrifos is currently under review. A public comment period will begin later this year. In the meantime, urge EPA to complete the chlorpyrifos ban.
Source: Columbia University Mailman School of Public Health