Background: Exposure to pollution is a significant risk to human health. However few studies have attempted to identify the types of policy interventions that can effectively reduce the health risks of pollution exposure.

Objectives: The study objective was to conduct a realist review of policy interventions conducted or aimed at reducing chemical exposures in humans or the environment where exposure was measured.

Methods: A literature search identified published articles that assessed policy interventions using exposure data. Two coders independently extracted data from the studies, assessing methods, context, details of interventions, outcomes, and risks of bias. Data were analyzed iteratively and manually to identify the most effective and transferrable types of interventions. The reasons for variability in the success of different interventions were explored.

Results: The review found that regulatory interventions that eliminate point sources of pollution were most effective in reducing exposure to environmental hazards. Regular monitoring to provide environmental and human exposure data may also be needed in order to assess compliance with the regulatory standards. Educational and economic interventions were less successful.

Conclusions: Although regulatory interventions appear to be the most effective, our findings are limited by the details on implementation provided in the included studies. Information on contextual factors that influence implementation would assist with future reviews and could help identify other effective interventions.