Air and Climate Epidemiology Section, Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA, USA.
Bay Area Air Quality Management District, San Francisco, CA, USA.
Sci Total Environ. 2021 Sep 15;787:147507. doi: 10.1016/j.scitotenv.2021.147507. Epub 2021 May 4.
Recent increases in wildfire frequency and severity necessitate better understanding of health effects of wildfire smoke to protect affected populations.
We examined relationships between fine particulate matter (PM) and morbidity during wildfires in California, and whether those relationships differed during the fire compared to a similar non-fire period.
For nine San Francisco Bay Area counties, daily county-level diagnosis-specific counts of emergency department visits (EDVs) and hospitalizations were linked with county-level estimates of daily mean PM during the October 2017 Northern California wildfires and similar October days in 2015, 2016, and 2017. Associations were estimated using Poisson regression.
The median difference between county PM during the fire versus the non-fire period was 23.4 μg/m, with days exceeding 80 μg/m in some counties. Over the entire study period, PM was most consistently linked to EDVs for respiratory disease (RR(lag0) per 23.4 μg/m increase: 1.25, 95% CI: 1.21, 1.30), asthma, chronic lower respiratory disease (CLRD; RR(lag0): 1.18, 95% CI: 1.10, 1.27), and acute myocardial infarction (RR(lag0): 1.14, 95% CI: 1.03, 1.25). Increases in acute upper respiratory infections and decreases in mental/behavioral EDVs were observed but were sensitive to model specification, specifically the inclusion of time-related covariates. Comparing fire and non-fire period EDV associations, we observed indications that PM during the fire was more strongly associated with asthma (RR: 1.46, 95% CI: 1.38, 1.55) compared to non-fire period PM (RR: 0.77, 95% CI: 0.55, 1.08) and the opposite observed for dysrhythmia, with the asthma difference being particularly robust to model choice. For hospitalizations, the most robust PM relationships were positive associations with respiratory, CLRD, and diabetes, and inverse associations with pneumonia. Respiratory and CLRD effect estimates were generally similar or smaller than for EDVs.
Elevated short-term PM levels from wildfire smoke appears to impact respiratory and other health domains.
野火频率和严重程度的增加要求我们更好地了解野火烟雾对健康的影响，以保护受影响人群。
我们研究了加利福尼亚野火期间细颗粒物 (PM) 与发病率之间的关系，以及与类似非火灾时期相比，这些关系在火灾期间是否有所不同。
对于旧金山湾区的九个县，将每日县级特定诊断的急诊就诊 (EDV) 和住院人数与 2017 年 10 月北加州野火期间以及 2015 年、2016 年和 2017 年同期类似 10 月的县级每日平均 PM 进行了关联。使用泊松回归估计关联。
在火灾期间与非火灾期间相比，县 PM 的中位数差异为 23.4μg/m，一些县的 PM 超过 80μg/m。在整个研究期间，PM 与呼吸系统疾病的 EDV 最一致相关 (每增加 23.4μg/m 的 RR(lag0)：1.25，95%CI：1.21，1.30)，哮喘，慢性下呼吸道疾病 (CLRD;RR(lag0):1.18,95%CI:1.10,1.27) 和急性心肌梗死 (RR(lag0):1.14,95%CI:1.03,1.25)。观察到急性上呼吸道感染增加和精神/行为 EDV 减少，但对模型规范敏感，特别是包括时间相关协变量。比较火灾和非火灾期间 EDV 关联，我们观察到指示表明，与非火灾期间 PM 相比，火灾期间 PM 与哮喘的相关性更强 (RR：1.46，95%CI：1.38，1.55)，而心律失常则相反，哮喘差异对模型选择特别稳健。对于住院治疗，与呼吸系统、CLRD 和糖尿病呈正相关，与肺炎呈负相关，与 PM 呈最稳健的关系。呼吸道和 CLRD 的影响估计通常与 EDV 相似或更小。
野火烟雾中短期 PM 水平升高似乎会影响呼吸道和其他健康领域。
