State-level drivers of future fine particulate matter mortality in the United States

Future fine particulate matter (PM₂.₅) concentrations and resulting health impacts will be largely determined by factors such as energy use, fuel choices, emission controls, state and national policies, and demographcs. In this study, a human-earth system model is used to estimate PM_2.5 mortality costs (PMMC) due to air pollutant emissions from each US state over the period 2015 to 2050, considering current major air quality and energy regulations. Contributions of various socioeconomic and energy factors to PMMC are quantified using the Logarithmic Mean Divisia Index. National PMMC are estimated to decrease 25% from 2015 to 2050, driven by decreases in energy intensity and PMMC per unit consumption of electric sector coal and transportation liquids. These factors together contribute 68% of the decrease, primarily from technology improvements and air quality regulations. States with greater population and economic growth, but with fewer clean energy resources, are more likely to face significant challenges in reducing future PMMC from their emissions. In contrast, states with larger projected decreases in PMMC have smaller increases in population and per capita GDP, and greater decreases in electric sector coal share and PMMC per unit fuel consumption.

[Emission Inventory and Prediction of Non-road Machineries in the Yangtze River Delta Region, China]

An air pollutant emission inventory of non-road machineries for the Yangtze River Delta (YRD) region was developed, based on local surveys and relative indicator predictions for cities in the region. Population, fuel consumption, and air pollutant emissions of non-road machineries were predicted for the period 2005 to 2025. The population of non-road machineries in the YRD region in 2014 was 8.23×10⁶ units, diesel consumption was about 9.95×10⁶ t, and SO₂, NO_x, CO, VOCs, PM₁₀, and PM_2.5 emissions were 5.5×10³, 4.9×10⁵, 7.6×10⁵, 1.1×10⁵, 2.9×10⁴, and 2.7×10⁴ t, respectively. Agricultural machineries accounted for 93% of the total population, with their CO and VOC emissions contributing 88% and 77% of respective totals. Construction machineries contributed 49% and 35% of NO_x and PM_2.5 emissions. Air pollutant emissions from non-road machineries were mainly concentrated in the middle and northern cities of the YRD region. During the period 2005-2014, the growth rates of population, fuel consumption, and air pollutant emissions of non-road machineries in the YRD region were relatively high. It is estimated that growth will be slowing down in 2020 and 2025. Diesel consumption will increase by 2% and 8% in 2020 and 2025, respectively, compared with 2014 levels. By 2020, SO₂, NO_x, CO, VOCs, PM₁₀, and PM_2.5 emissions will decrease by 97%, 10%, 3%, 10%, 11%, and 11%, respectively; by 2025, these decreases will reach 97%, 16%, 3%, 15%, 21%, and 21%, respectively. It is expected that air pollutant emissions from non-road machineries will continue to decline in future. However, the decreasing trend of NO_x, VOCs, and PM_2.5 emissions from motor vehicles reached 22%, 50%, and 48%, much greater than that of non-road machinery. The emission contributions of non-road machinery will become increasingly significant in future. It is necessary to accelerate the scrappage of old machinery and to further promote emission standards for new machinery to reduce emissions from non-road machineries.