Current Evidence for the Association between Air Pollution and Parkinson's Disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder, and its global incidence is on the rise. There is increasing interest in understanding the role of air pollution in the development of human disease. Although the precise mechanisms are not understood, several epidemiological studies have reported a positive association between air pollution and the risk of PD. However, the various pollutants studied, endpoints measured, and differences in study design yield conflicting results. This review summarizes recent evidence regarding the relationship between particulate matter, ozone, nitrogen dioxide, sulfur dioxide, and carbon monoxide and PD. Limitations and challenges are also discussed, with suggestions for future work to understand the true effects of air pollution on PD.