A study involving 725 black and Dominican pregnant women living in New York and, later, their 3-year-old children, has found that children who were more highly exposed to PBO in personal air samples taken during the third trimester of pregnancy scored 3.9 points lower on the Bayley Mental Developmental Index than those with lower exposures. This is a similar effect size to that of lead exposure.
PBO is a marker for the insecticide permethrin, which is one of the most common pyrethroid insecticides used in U.S. homes since the EPA phased out the widespread residential use of organophosphorus insecticides in 2000-2001 because of risks to child neurodevelopment.
PBO was detected in the majority of personal air samples (75%).
As this is the first study of these compounds, the results should be considered preliminary.
(2011). Impact of Prenatal Exposure to Piperonyl Butoxide and Permethrin on 36-Month Neurodevelopment.
Pediatrics. 127(3), e699-706 - e699-706.