Air pollution and the epigenome: A model relationship for the exploration of toxicoepigenetics

- The relationship (associative or causal) between air pollution, the epigenome, and health effects remains to be characterized.
- Most studies use peripheral leukocytes as a surrogate, but their epigenetic relationship with affected tissues is unclear.
- The roles of >130 epigenetic modifications in air pollution epigenetics remain relatively unexplored.
- New approaches (e.g. CRISPR-dCas9-targeting) can determine the roles of epigenetic changes in exposure effects.
- This review discusses cross-field perspectives to increasing the application of epigenetic data in air pollution research.

The field of toxicoepigenetics is rapidly emerging to provide new insights into the relationship between environmental factors, the epigenome, and public health. Toxicoepigenetic data have the potential to revolutionize our understanding of environmental exposure effects and susceptibility. Studies in recent years have demonstrated that exposure to air pollution alters epigenetic modification states; however, continued advancement of the field is limited by the intrinsic complexity of the epigenome and inherent limitations of different types of studies (epidemiological, clinical, and in vitro) that are used in toxicoepigenetics. Overcoming these challenges will require a concerted and collaborative effort between molecular and cellular biologists, toxicologists, epidemiologists, and risk assessors to develop a thorough and practical understanding of the relationship between air pollution exposure, the epigenome, and health effects. Here we review the current state of air pollution epigenetics and discuss perspectives on the necessary steps to move the field forward to determine the role that the epigenome plays in air pollution exposure effects and susceptibility.