成都市气温与PM2.5和O3交互作用对疾病死亡人数的影响研究

利用成都市2014~2016年逐日呼吸系统疾病和心脑血管疾病死亡资料、同期气象资料和PM_2.5日均浓度和每日臭氧最大8h平均浓度（O₃）资料，采用分布滞后模型以及广义相加模型中的独立效应模型、非参数二元响应模型和温度分层模型探究了成都市气温、PM_2.5和O₃单效应，以及气温与PM_2.5（或O₃）交互作用对当地呼吸和心脑血管疾病死亡人数的影响.单效应分析结果表明，气温与两种疾病死亡人数的累计暴露-反应关系均呈反“J”型分布，最适温度在22.2℃，该温度对应的疾病死亡人数最少；累积滞后1d的PM_2.5（或O₃）对应的健康风险最大，此时，PM_2.5和O₃浓度每升高10μg/m³，呼吸系统疾病死亡风险分别增加0.58%和0.54%，心脑血管疾病死亡风险分别增加0.35%和0.66%.分季节研究结果表明，PM_2.5对两种疾病死亡影响的健康风险冬季最高，而O₃的健康风险在秋季最显著.交互作用的研究结果表明，高温与高浓度的PM_2.5（或O₃）对疾病死亡的影响存在协同放大效应，当气温高于22.2℃时，PM_2.5和O₃浓度每升高10μg/m³，对应的呼吸系统疾病死亡风险分别增加2.30%和1.14%，心脑血管疾病死亡风险分别增加1.09%和1.03%.研究结果提示O₃对人群健康的影响也不容忽视，应该引起足够的重视.

Interaction effects between ambient temperature and PM2.5 and O3 on mortality in Chengdu

Daily death data of respiratory and cardiovascular diseases during 2014~2016, meteorological data and daily average particulate matter with aerodynamic less than 2.5 (PM_2.5) and daily ozone 8h maximum concentration (O₃) during the same time period in Chengdu were collected. Distributed Lag Non-linear Model (DLNM) and three semi-parametric Generalized Additive Models (GAMs), including an independent model, a nonparametric bivariate response surface model, and a stratification parametric model, were adopted to explore the adverse health effects of temperature, air pollutants (PM_2.5 and O₃) and the synergistic effects between temperature and PM_2.5(or O₃) on respiratory and cardiovascular system diseases, respectively. The results of single-effect studies showed that the exposure-response relationships between ambient temperature and respiratory and cardiovascular diseases both exhibited inverse "J" type and the most comfortable temperature were 22.2℃, which corresponding to the least mortality. The health risks were strongest between the current and previous day (lag01) average concentrations of PM_2.5 and O₃. Per 10 μg/m³ increment in PM_2.5 and O₃ were associated with 0.58% and 0.54% increase in respiratory mortality and 0.35% and 0.66% increases in cardiovascular mortality, respectively. The combined effects between the temperature and different air pollutant on human health suggested that the mortality reach the maximum when high temperature and high mass concentrations of PM_2.5 (or O₃) coexisted. Furthermore, the results of seasonal study showed that PM_2.5 had the highest health risk on mortality in winter and O₃ had the most significant health risk in autumn. Furthermore, the results of interaction study showed that there was a synergistic amplification effect between high temperature and high concentration of PM_2.5 (or O₃) on mortality. Under high temperature, per 10 μg/m³ increment in PM_2.5 and O₃ were associated with 2.30% and 1.14% increase in respiratory mortality and 1.09% and 1.03% increases in cardiovascular mortality, respectively. We should also pay more attention to the adverse effect of O₃ on human health in the future.