Pesticide-monitoring results suggest that a shift in residential pesticide exposure from organophosphorus insecticides to pyrethroid insecticides has occurred. However, pyrethroid insecticides are also potential neurodevelopmental toxicants and have not been evaluated for developmental toxicity. This study investigated the association between prenatal exposure to permethrin (a common pyrethroid) and piperonyl butoxide (a pyrethroid synergist) and neurodevelopment at 36-months. Participants (n=348) were part of a prospective cohort of black and Dominican mothers and newborns living in low-income neighborhoods in New York City. We examined 36-month cognitive and motor development using the Bayley Scales of Infant Development as a function of 1) permethrin levels measured in maternal and umbilical cord plasma collected on delivery and 2) permethrin and piperonyl butoxide levels measured in personal air collected during pregnancy. Prenatal exposure to permethrin in personal air and/or plasma was not associated with performance scores for the Bayley Mental Developmental Index or the Psychomotor Developmental Index. Pediatrics. 2011 Feb 14. PMID: 21300677.
