Environmental risk factors for liver cancer and nonalcoholic fatty liver disease
PURPOSE OF REVIEW:
The objective of this review was to summarize recent epidemiologic research examining the associations between environmental exposures and liver cancer and nonalcoholic fatty liver disease (NAFLD).
There were 28 liver cancer studies showing positive associations for exposures to aflatoxin, air pollution, polycyclic aromatic hydrocarbons, asbestos, chimney sweeping occupation, and paints; an inverse association for ultraviolet radiation; and null/inconsistent results for organic solvents, pesticides, perfluorooctanoic acid, nuclear radiation, iron foundry occupation, and brick kiln pollution. There were n=5 NAFLD studies showing positive associations for heavy metals, methyl tertiary-butyl ether, and selenium; and no association with trihalomethanes.
Evidence suggests that particular environmental exposures may be associated with liver cancer and NAFLD. Future liver cancer studies should examine specific histological subtypes and assess historical environmental exposures. Future NAFLD research should examine incident, biopsy-confirmed cases and the potential role of obesity and/or diabetes in studies of environmental factors and NAFLD.
1. Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.