Impact of microplastic exposure on emotional and behavioral development in school-aged children: the moderating role of diet

At present, the impact of microplastic (MP) exposure on children’s emotional and behavioral development remains unclear. Moreover, empirical research on the potential interaction between MP exposure and dietary patterns is particularly scarce, which constitutes a key research gap in this field. A total of 1234 10-year-old children were enrolled in this cross-sectional study. Laser Direct Infrared spectroscopy was utilized to quantify and identify the types and abundances of MPs in urine samples. We used a multiple linear regression model to analyze the effects of MP exposure and dietary adherence on children’s emotional and behavioral development, and further conducted a stratified analysis based on dietary adherence. The study revealed that the detection rate of MPs among 10-year-old school-aged children reached 91.41%, with a median abundance of 250 particles/mL. In boys, urinary polytetrafluoroethylene (PTFE) abundance was positively correlated with T-scores for Rule-Breaking Behavior (β = 0.165; 95%CI: 0.026,0.305) and Externalizing Problems (β = 0.249; 95%CI: 0.001,0.496). Higher Mediterranean diet adherence was significantly associated with lower Total Problems scores (β = −0.383; 95%CI: −0.620, −0.146). Significant negative associations were also observed for Withdrawn/Depressed, Thought Problems, Attention Problems, Internalizing Problems, and Externalizing Problems. These associations were more pronounced in girls. Stratified analyses showed that in the low or moderate adherence group, polyamide (PA) was significantly positively associated with Total Problems (β = 0.244; 95% CI: 0.015, 0.473). Significant positive associations were also observed for Anxious/Depressed (β = 0.126; 95% CI: 0.007, 0.245), Social Problems (β = 0.199; 95% CI: 0.071, 0.326), Rule-Breaking Behavior (β = 0.156; 95% CI: 0.041, 0.271), and Externalizing Problems (β = 0.246; 95% CI: 0.036, 0.455). These associations were more pronounced in boys. In conclusion, MP exposure was associated with sex-specific differences in children’s emotional and behavioral development, and higher adherence to the Mediterranean diet was associated with a reduced magnitude of these adverse associations.