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This study aimed to investigate the association between long-term exposure to fine particulate matter (PM 2.5) and its constituents (black carbon (BC), ammonium (NH 4 +), nitrate (NO 3 −), organic matter (OM), inorganic sulfate (SO 4 2−)) and incident female breast cancer in Beijing, China. Data from a prospective cohort comprising 85,504 women enrolled in the National Urban Cancer Screening Program in Beijing (2013–2019) and the Tracking Air Pollution in China dataset are used. Monthly exposures were aggregated to calculate 5-year average concentrations to indicate long-term exposure. Cox models and mixture exposure models (weighted quantile sum, quantile-based g-computation, and explanatory machine learning model) were employed to analyze the associations. Findings indicated increased levels of PM 2.5 and its constituents were associated with higher breast cancer risk, with hazard ratios per 1-μg/m3 increase of 1.02 (95% confidence interval (CI): 1.01, 1.03), 1.39 (95% CI: 1.16, 1.65), 1.28 (95% CI: 1.12, 1.46), 1.15 (95% CI: 1.05, 1.24), 1.05 (95% CI: 1.02, 1.08), and 1.15 (95% CI: 1.07, 1.23) for PM 2.5 , BC, NH 4 +, NO 3 −, OM, and SO 4 2−, respectively. Exposure-response curves demonstrated a monotonic risk increase without an evident threshold. Mixture exposure models highlighted BC and SO 4 2− as key factors, underscoring the importance of reducing emissions of these pollutants. [Display omitted] • Long-term exposure to PM 2.5 and its constituents was linked to higher female breast cancer risk in Beijing. • Key pollutants black carbon (BC) and sulfate (SO 4 2−) were identified as significant contributors to breast cancer risk. • Effective control measures are crucial in mitigating pollutants to reduce the risk of female breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: It is recognized that information on both quantity and composition of residential waste is important for the effective planning of household waste handling infrastructure. In this paper, we present the results of a survey on household waste generation and composition in Beijing, China. Sample communities were selected by the integration of five indices including family population, income, age, and education. Wastes were sampled on a daily basis from 113 households in six different districts of Beijing City for ten days. The results showed that the generation rate of household wastes was 0.23kg/pers/day. The bulk density was approximately 221kg/m3, and the moisture content was approximately 50%. Household waste consisted of kitchen waste, paper/cardboard, plastics, textiles, metals, glass and other wastes, the proportion of each waste was approximately 69.3%, 10.3%, 9.8%, 1.3%, 0.8%, 0.6% and 2.7%, respectively. An evaluation of the relationship between daily per capita generation of household waste and socio-economic factors indicated that household size and income both showed a negative relationship with household waste generation (kg/pers/day). As for the effect of education, families with a secondary educational level produced fewer household wastes (kg/pers/day) than those with a primary or advanced educational level. [Copyright &y& Elsevier]