PM2.5 constituents and mortality from a spectrum of causes in Guangzhou, China

As the major constituents of PM2.5, carbonaceous constituents and inorganic ions have attracted emerging attentions on their health risks, particularly on cardiorespiratory diseases. However, evidences on the risks of PM2.5 constituents on other diseases (eg. nervous disease, genitourinary disease, neoplasms and endocrine disease) remain scarce. In our study, we firstly calculated residuals of PM2.5 constituents regressed on PM2.5 to remove the confounding effect of PM2.5. Then, generalized additive model (GAM) was used to assess impacts of residuals of PM2.5 constituents on mortality from 36 diseases (10 broad categories and 26 subcategories) during 2011–2015 in Guangzhou, China. Results of constituent-residual models showed that only EC, OC and NO3- were significantly associated with all-cause mortality, with per IQR change in corresponding constituent residuals related to percentage changes of 1.69% (95% CI: 0.42, 2.97), 1.94% (95% CI: 0.37, 3.54) and 2.59% (95% CI: 1.02, 4.18) at lag 03 days. All these pollutants were significantly associated with elevated mortality risk of cardiovascular disease, but only EC was significantly associated with respiratory mortality, and NO3- with endocrine disease and neoplasm. For more specific causes, the highest effect estimates of EC and NO3-were both observed on mortality from other form of heart disease, and OC on intentional self-harm, with estimates of 11.45% (95% CI: 2.74, 20.91), 12.59% (95% CI: 1.41, 25.02) and 18.01% (95% CI: 2.14, 36.36), respectively. Our findings highlighted that stricter emission control measures are still warranted to reduce air pollution level and protect the public health. The association between PM2.5 and its constituents and cause-specific mortality. [Display omitted] •We explored independent effects of PM2.5 constituents on mortality from 36 diseases.•EC, OC andNO3- were significantly associated with cardiovascular mortality.•EC was significantly associated with respiratory mortality.•NO3- was significantly associated with deaths of endocrine disease and neoplasm.