Exposure to certain chemicals in the environment may contribute to the risk of developing
cancer. Although
cancer risk from environmental chemical exposure among general populations is considered low compared to that in occupational settings, many people may nevertheless be chronically exposed to relatively low levels of environmental chemicals which vary by such various factors as residential area, lifestyle, and dietary habits. It is therefore necessary to assess population-specific exposure levels and examine their association with
cancer risk. Here, we reviewed epidemiological evidence on
cancer risk and exposure to dichlorodiphenyltrichloroethane (
DDT),
hexachlorocyclohexane (HCH),
polychlorinated biphenyls (
PCBs),
per- and polyfluoroalkyl substances (PFASs),
cadmium,
arsenic, and acrylamide. Japanese are widely exposed to these chemicals, mainly through the diet, and an association with increased
cancer risk is suspected. Epidemiological evidence from Japanese studies to date does not support a positive association between blood concentrations of
DDT, HCH,
PCBs, and PFASs and risk of breast or
prostate cancer. We established assessment methods for dietary intake of
cadmium,
arsenic, and acrylamide using a food frequency questionnaire. Overall, dietary intakes of
cadmium,
arsenic, and acrylamide were not significantly associated with increased risk of total
cancer and major
cancer sites in the Japan Public Health Center-based Prospective Study. However, statistically significant positive associations were observed between dietary
cadmium intake and risk of
estrogen receptor-positive
breast cancer among postmenopausal women, and dietary
arsenic intake and risk of
lung cancer among male smokers. In addition, studies using
biomarkers as exposure assessment revealed statistically significant positive associations between urinary
cadmium concentration and risk of
breast cancer, and between ratio of
hemoglobin adducts of acrylamide and
glycidamide and risk of
breast cancer. Epidemiological studies of general populations in Japan are limited and further evidence is required. In particular, studies of the association of organochlorine and organofluorine compounds with risk of
cancer sites other than breast and
prostate cancer are warranted, as are large prospective studies of the association between
biomarkers of exposure and risk of
cancer.