Prenatal and childhood exposure to pesticides and neurobehavioral development: Review of epidemiological studies

Objectives: Conventional pesticides comprise a diverse group of substances intended to destroy, repel or control organisms identified as pests. Compared to the studies on lead, mercury, and PCBs, few epidemiological studies have assessed the developmental neurotoxicity of pesticides. Materials and Methods: Epidemiological studies focused on the neurobehavioural development of children exposed to pesticides were identified by searching the PubMed, Medline, EBSCO, Agricola and TOXNET databases. Results: The findings of the studies reviewed imply that children's exposure to pesticides may bring about impairments in their neurobehavioral development. Children exposed to organophosphate pesticides (OP), both prenatally and during childhood, may have difficulties performing tasks that involve short-term memory, and may show increased reaction time, impaired mental development or pervasive developmental problems. In newborns, the effects of OP exposure are manifested mainly by an increased number of abnormal reflexes, while in adolescents, by mental and emotional problems. The studies investigating association between exposure to organochlorine pesticides and neurodevelopmental effects show inconsistent results. While some studies report impairments in mental and psychomotor functions, other studies do not confirm the above. Conclusion: The information deriving from epidemiological studies indicate a need to increase awareness among people and children exposed to pesticides about the association between the use of pesticides and neurodevelopmental impairments. Therefore, the principle of prudence should become a rule.