Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; Department of Civil, Construction and Environmental Engineering, North Carolina State University, Campus Box 7908, Raleigh, NC, 27695-7908, United States.
Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; Environmental Protection Department of HKSAR Government, 33/F, Revenue Tower, 5 Gloucester Road, Wanchai, Hong Kong, China.
Environ Pollut. 2021 Feb 1;270:116280. doi: 10.1016/j.envpol.2020.116280. Epub 2020 Dec 13.
The reduction of NO emissions in a VOC-limited region can lead to an increase of the local O concentration. An evaluation of the net health effects of such pollutant changes is therefore important to ascertain whether the emission control measures effectively improve the overall protection of public health. In this study, we use a short-term health risk (added health risk or AR) model developed for the multi-pollutant air quality health index (AQHI) in Hong Kong to examine the overall health impacts of these pollutant changes. We first investigate AR changes associated with NO and O changes, followed by those associated with changes in all four AQHI pollutants (NO, O, SO, and particulate matter (PM)). Our results show that for the combined health effects of NO and O changes, there is a significant reduction in AR in urban areas with dense traffic, but no statistically significant changes in other less urbanized areas. The increase in estimated AR for higher O concentrations is offset by a decrease in the estimated AR for lower NO concentrations. In areas with dense traffic, the reduction in AR as a result of decreased NO is substantially larger than the increase in AR associated with increased O. When additionally accounting for the change in ambient SO and PM, we found a statistically significant reduction in total AR everywhere in Hong Kong. Our results show that the emission control measures resulting in NO, SO, and PM reductions over the past decade have effectively reduced the AR over Hong Kong, even though these control measures may have partially contributed to an increase in O concentrations. Hence, efforts to reduce NOx, SO, and PM should be continued.
在 VOC 受限地区减少 NO 排放可能会导致局部 O 浓度增加。因此，评估此类污染物变化对净健康影响对于确定排放控制措施是否有效改善公众健康的整体保护非常重要。在这项研究中，我们使用香港多污染物空气质量健康指数 (AQHI) 短期健康风险 (附加健康风险或 AR) 模型来研究这些污染物变化对整体健康的影响。我们首先调查了与 NO 和 O 变化相关的 AR 变化，然后调查了与所有四种 AQHI 污染物（NO、O、SO 和颗粒物 (PM)）变化相关的 AR 变化。我们的结果表明，对于 NO 和 O 变化的综合健康影响，在交通密集的城区，AR 显著降低，但在其他非城市化程度较低的地区，没有统计学意义上的变化。较高 O 浓度引起的估计 AR 增加被较低 NO 浓度引起的估计 AR 减少所抵消。在交通密集的地区，由于 NO 减少而导致的 AR 减少量大大超过由于 O 增加而导致的 AR 增加量。当另外考虑环境 SO 和 PM 的变化时，我们发现香港各地的总 AR 显著减少。我们的结果表明，过去十年中由于减少 NO、SO 和 PM 而采取的排放控制措施有效地降低了香港的 AR，尽管这些控制措施可能部分导致 O 浓度增加。因此，应该继续努力减少氮氧化物、硫氧化物和颗粒物。
