Environmental pollution and risk of psychotic disorders: A review of the science to date.

Environmental pollution is a global problem with diverse and substantial public health implications. Although many environmental (i.e., non-genetic) risk factors for schizophrenia and other psychotic disorders have been identified, there has been comparatively little research on pollution as a possible risk factor. This is despite the fact that gene-by-environment interactions and epigenetic mechanisms are now recognized as likely facets of the etiology of schizophrenia, and the fact that pollution could potentially mediate the association between urban birth/upbringing and elevated risk. We conducted a review of the literature to date in order to summarize and synthesize work in this area. We identified 13 research reports and 16 review articles. Based on the extant knowledge in this area and what is known about the pathophysiology of schizophrenia, it is feasible that exposure to xenobiotic heavy metals such as lead and cadmium, constituents of air pollution such as particulate matter and nitrogen and sulfur oxides, organic solvents, and other constituents of environmental pollution could be component causes. Further research-from the cellular to epidemiological levels-is clearly needed. If causation is proven, enhancements of policy intended to reduce human exposure to environmental pollution could reduce the burden of schizophrenia and possibly other mental illnesses.