Prenatal particulate matter exposure is linked with neurobehavioural development in early life

Early life exposure to ambient particulate matter (PM) may negatively affect neurobehavioral development in children, influencing their cognitive, emotional, and social functioning. Here, we report a study on prenatal PM_2.5 exposure and neurobehavioral development focusing on different time points in the first years of life.

This study was part of the ENVIRONAGE birth cohort that follows mother-child pairs longitudinally. First, the Neonatal Behavioral Assessment Scale (NBAS) was employed on 88 newborns aged one to two months to assess their autonomic/physiological regulation, motor organisation, state organisation/regulation, and attention/social interaction. Second, our study included 393 children between the ages of four and six years, for which the Strengths and Difficulties Questionnaire (SDQ) was used to assess the children's emotional problems, hyperactivity, conduct problems, peer relationship, and prosocial behaviour. Prenatal PM_2.5 exposure was determined using a high-resolution spatial-temporal method based on the maternal address. Multiple linear and multinomial logistic regression models were used to analyse the relationship between prenatal PM_2.5 exposure and neurobehavioral development in newborns and children, respectively.

A 5 μg/m³ increase in first-trimester PM_2.5 concentration was associated with lower NBAS range of state cluster scores (-6.11%; 95%CI: -12.00 to -0.23%; p = 0.04) in one-to-two-month-old newborns. No other behavioural clusters nor the reflexes cluster were found to be associated with prenatal PM_2.5 exposure. Furthermore, a 5 μg/m³ increment in first-trimester PM_2.5 levels was linked with higher odds of a child experiencing peer problems (Odds Ratio (OR) = 3.89; 95%CI: 1.39 to 10.87; p = 0.01) at ages four to six. Additionally, a 5 μg/m³ increase in second-trimester PM_2.5 concentration was linked to abnormal prosocial behaviour (OR = 0.49; 95%CI: 0.25 to 0.98; p = 0.04) at four to six years old. No associations were found between in utero PM_2.5 exposure and hyperactivity or conduct problems.

Our findings suggest that prenatal exposure to PM may impact neurobehavioural development in newborns and preschool children. We identified sensitive time windows during early-to-mid pregnancy, possibly impacting stage changes in newborns and peer problems and prosocial behaviour in children.