Prenatal mercury exposure is associated with a higher risk of ADHD in children, while fish consumption during pregnancy is associated with a lower risk. Exposure to organophosphate pesticides also affects neural systems and may contribute to ADHD symptoms.
Sagiv SK, Thurston SW, Bellinger DC, Amarasiriwardena C, Korrick SA. Prenatal Exposure to Mercury and Fish Consumption During Pregnancy and Attention-Deficit/Hyperactivity Disorder–Related Behavior in Children. Archives of Pediatrics & Adolescent Medicine, 2012
Maryse F. Bouchard, David C. Bellinger, Robert O. Wright, and Marc G. Weisskopf. Attention-Deficit/Hyperactivity Disorder and Urinary Metabolites of Organophosphate Pesticides. Pediatrics, 2010