Comparing the risks of environmental carcinogenic chemicals in Japan using the loss of happy life expectancy indicator

In this study, we aimed to use the loss of happy life expectancy (LHpLE), an indicator that enables risk assessment considering wellbeing, to compare the risks of environmental carcinogenic chemicals in Japan. First, we surveyed Japanese people to determine their emotional happiness by age and sex and evaluated whether cancer incidence reduced emotional happiness. Questionnaires were administered to a general population panel and a panel of patients with cancer in 2022, recruiting a predetermined number of responses of 5000 and 850, respectively. Second, using the survey data, LHpLE was calculated for radon, arsenic, and fine particulate matter (aerodynamic diameter <2.5 μm; PM 2.5 ) and compared to psychological distress, considering increased mortality and decreased emotional happiness due to these risks. We discovered no significant decrease in emotional happiness due to cancer incidence and no significant associations between emotional happiness and cancer type, history, or stage. LHpLE was calculated to be 6.4 × 10 −3 years for radon, 2.6 × 10 −3 years for arsenic, 1.1 × 10 −2 years (2012 exposure) and 8.6 × 10 −4 years (2020 exposure) for PM 2.5 , and 9.7 × 10 −1 years for psychological distress. The fraction of losses caused by these carcinogenic chemicals to HpLE exceeded 10 −5 , suggesting that risk reduction for these chemicals is important in environmental policies. The LHpLE indicator allows for comparing different types of risks, such as environmental chemicals and psychological distress. This is the first study to compare chemical risks using the LHpLE indicator.