[Health Impact Analysis of Fine Particulate Pollution from Vehicles in the Beijing-Tianjin-Hebei Region].

Vehicle exhaust emissions are posing an increasingly adverse impact on urban air quality. The emission characteristics analysis and health effect assessment of specific air pollution sources can provide scientific evidence for environmental air quality management. The characteristics and health effects of PM2.5 emissions from vehicles and economic losses caused by them in the Beijing-Tianjin-Hebei Region were analyzed from 2010 to 2020. From 2010 to 2020, PM2.5 emissions from vehicles in the Beijing-Tianjin-Hebei Region showed an annual increase at first, followed by a slow decrease. According to the emission sharing ratios of different vehicle types, heavy-duty trucks and buses were the main contributors to PM2.5, with a total contribution rate of over 65.27%. The emission characteristics of vehicle pollutants varied in different cities. The contribution rate of pollutants in Beijing decreased significantly, and the emission reduction in other cities was also dramatic. The evaluation results of the impact of PM2.5 emissions from vehicles on human health showed that the number of health endpoints in the Beijing-Tianjin-Hebei Region was on the rise. In 2020, PM2.5 pollution caused approximately 34337 premature deaths (95% CI:9025-57209), 45500 hospitalizations (95% CI:10800-80200), 282300 outpatients (95% CI:140500-416300), and 439000 people to fall ill (95% CI:160300-679200). Beijing had the largest number of patients that presented different health endpoints. The total health and economic losses caused by PM2.5 emissions from vehicles in 2010, 2015, and 2020 were 27.742 billion yuan (95% CI:8.616-44.643 billion yuan), 90.608 billion yuan (95% CI:28.476-144.050 billion yuan), and 129.965 billion yuan (95% CI:40.829-205.245 billion yuan), respectively. In addition, due to the differences in vehicle ownership, PM2.5 concentrations, population, and economic losses per case of health outcome, the health effects and economic losses varied in different cities within the region. Among these cities, Beijing, Tianjin, Baoding, and Tangshan were at higher health risks and suffered more economic losses. The results of this study will help reduce the adverse effects on health and economic losses caused by pollution discharge and provide scientific evidence for environmental protection authorities to implement targeted pollution prevention and control.

[Application of Pu isotope tracing technique in soil erosion research]. / PuåŒä½ç´ ç¤ºè¸ªæŠ€æœ¯åœ¨åœŸå£¤ä¾µèš€ç ”ç©¶ä¸­çš„åº”ç”¨.

As an essential form of material migration on the surface of the earth, soil erosion is one of the primary causes of soil fertility reduction and environmental degradation. Quantifying soil erosion rate is the precondition and foundation for regional soil erosion control. The Pu isotopes produced by atmospheric nuclear tests have a long half-life after settling into the soil and could be easily adsorbed by clay minerals and organic matter. In recent years, Pu isotopes have become principal trace elements in the quantitative studies of soil erosion rate, especially with the development of mass spectrometry technique. The measurement time of Pu isotopes has been shortened, and the sensitivity of Pu isotopes has been improved, both of which help improve the radionuclide tracing technology for soil erosion. Here, we summarized the distribution characteristics as well as the adsorption and migration behavior of Pu isotopes in soil. We described the basic principles for the application of Pu isotopes in tracing soil erosion, and elaborated the research progress concerning relevant applications. Moreover, we compared the applicability of Pu isotope and 137Cs tracing techniques in soil erosion research and proposed research directions in the future. This review would provide a reference for the scientific applications of Pu isotope tracing technique in soil erosion research.