Psychiatrists have not been attentive to the huge and expanding capacity of neurotoxic substances to induce symptoms of emotional and behavioral dysfunction. The psychiatric implications of exposure to heavy metals, volatile solvents, pesticides and behavioral teratogens is reviewed. Case histories reflect the risk of misdiagnosing psychotoxic episodes and the futility of standard interventions. The variability of behavioral responses to psychotoxic agents challenges a psychiatric nomenclature based on specific disease categories. Psychiatrists should routinely inquire about exposure to toxic substances. The issues raised will result in confrontation with social and economic forces usually ignored by clinicians.