Anemia is associated with long-term exposure to PM2.5 and its components: a large population-based study in Southwest China.

Background: Anemia is linked to PM2.5 (particulate matter with aerodynamic diameters of ⩽2.5 µm) exposure, which can increase the risk of various negative health outcomes. It remains unclear which PM2.5 components are associated with anemia and the respective contribution of each component to this association. Objective: This study aimed at investigating the association between PM2.5 and anemia in the general population and to identify the most critical PM2.5 toxic components in this association. Design: Cross-sectional study. Methods: Our study involved a large cohort of 73,511 individuals aged 30-79 from China's multi-ethnic population. We employed satellite observations and the chemical transport model (GEOS-Chem)to estimate the long-term exposure to PM2.5 and its components. Anemia was defined, according to WHO guidelines, as Hb levels below 130 g/L for men and below 120 g/L for women. Through logistic regression, we investigated the association between PM2.5 components and anemia. By utilizing weighted quantile sum (WQS) analysis, we identified key components and gained insights into their combined impact on anemia. Overall, our study sheds light on the relationship between PM2.5 exposure, its constituents, and the risk of anemia in a large cohort. Results: PM2.5 and three components, nitrate (NIT), organic matter (OM), and soil particles (SOIL), were associated with anemia. Per-standard deviation increase in the 3-year average concentrations of PM2.5 [odds ratio (OR): 1.14, 95% confidence interval (CI): 1.01, 1.28], NIT (1.20, 1.06, 1.35), OM (1.17, 1.04, 1.32), and SOIL (1.22, 1.11, 1.33) were associated with higher odds of anemia. In WQS regression analysis, the WQS index was associated with anemia (OR: 1.29, 95% CI: 1.13, 1.47). SOIL has the highest weight among all PM2.5 components. Conclusions: Long-term exposure to PM2.5 and its constituents is associated with anemia. Moreover, SOIL might be the most critical component of the relationship between PM2.5 and anemia. Our research increases the evidence of the association between PM2.5 and anemia in the general population, and targeted emission control measures should be taken into consideration to mitigate the adverse effects of PM2.5-related anemia.

The role of lipid profile in the relationship between particulate matters and hyperuricemia: A prospective population study.

CONTEXT: Recent studies in specific population subgroups (e.g., pregnant women) have suggested PM exposure increases the risk of hyperuricemia. However, no studies have examined this in the general population. Furthermore, the underlying mechanism through which PM impacts hyperuricemia risk is poorly understood. OBJECTIVE: To assess the association between long-term exposure to PM and risk of hyperuricemia and whether this association is mediated by lipid profile. METHODS: We included 5939 participants in Southwest China from the China Multi-Ethnic Cohort (baseline 2018-2019, follow-up 2020-2021). Long-term PM pollutants (PM1, PM2.5, PM10) exposure for each individual was represented by the three-year average PM levels before the baseline survey. Hyperuricemia at follow-up was defined as the serum uric acid above 7.0 mg/dL in men and 6.0 mg/dL in women. Serum lipids were measured at baseline including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG). The association of PM with hyperuricemia was accessed through logistic regression. The potential mediation effects of serum lipids were evaluated through causal mediation analyses. RESULTS: A total of 837 participants were newly diagnosed with hyperuricemia. The odds ratios of hyperuricemia associated with an interquartile range (IQR) increase in PM1, PM2.5, and PM10 (IQR: 21.10, 25.78, 30.43 µg m-3) were 1.72 (95% CI: 1.23, 2.39), 2.68 (95% CI: 1.59, 4.49), and 1.81 (95% CI: 1.20, 2.72), respectively. The association between PM2.5, PM1, and PM10 on hyperuricemia was mediated by HDL-C (10%) and LDL-C (3%). CONCLUSION: Higher particulate matter exposure was associated with higher hyperuricemia incidence. The decline in HDL-C and rise in LDL-C partially mediated this association. These findings were conducive to scientific research about the underlying mechanism of PM on hyperuricemia.