Jones Rena R, Hogrefe Christian, Fitzgerald Edward F, Hwang Syni-An, Özkaynak Halûk, Garcia Valerie C, Lin Shao
a New York State Department of Health , Center for Environmental Health , Albany , NY , USA.
J Air Waste Manag Assoc. 2015 May;65(5):559-69. doi: 10.1080/10962247.2014.1001500.
Despite observed geographic and temporal variation in particulate matter (PM)-related health morbidities, only a small number of epidemiologic studies have evaluated the relation between PM2.5 chemical constituents and respiratory disease. Most assessments are limited by inadequate spatial and temporal resolution of ambient PM measurements and/or by their approaches to examine the role of specific PM components on health outcomes. In a case-crossover analysis using daily average ambient PM2.5 total mass and species estimates derived from the Community Multiscale Air Quality (CMAQ) model and available observations, we examined the association between the chemical components of PM (including elemental and organic carbon, sulfate, nitrate, ammonium, and other remaining) and respiratory hospitalizations in New York State. We evaluated relationships between levels (low, medium, high) of PM constituent mass fractions, and assessed modification of the PM2.5-hospitalization association via models stratified by mass fractions of both primary and secondary PM components. In our results, average daily PM2.5 concentrations in New York State were generally lower than the 24-hr average National Ambient Air Quality Standard (NAAQS). Year-round analyses showed statistically significant positive associations between respiratory hospitalizations and PM2.5 total mass, sulfate, nitrate, and ammonium concentrations at multiple exposure lags (0.5-2.0% per interquartile range [IQR] increase). Primarily in the summer months, the greatest associations with respiratory hospitalizations were observed per IQR increase in the secondary species sulfate and ammonium concentrations at lags of 1-4 days (1.0-2.0%). Although there were subtle differences in associations observed between mass fraction tertiles, there was no strong evidence to support modification of the PM2.5-respiratory disease association by a particular constituent. We conclude that ambient concentrations of PM2.5 and secondary aerosols including sulfate, ammonium, and nitrate were positively associated with respiratory hospitalizations, although patterns varied by season. Exposure to specific fine PM constituents is a plausible risk factor for respiratory hospitalization in New York State.
The association between ambient concentrations of PM2.5 components has been evaluated in only a small number of epidemiologic studies with refined spatial and temporal scale data. In New York State, fine PM and several of its constituents, including sulfate, ammonium, and nitrate, were positively associated with respiratory hospitalizations. Results suggest that PM species relationships and their influence on respiratory endpoints are complex and season dependent. Additional work is needed to better understand the relative toxicity of PM species, and to further explore the role of co-pollutant relationships and exposure prediction error on observed PM-respiratory disease associations.
尽管观察到与颗粒物（PM）相关的健康发病率存在地理和时间差异，但仅有少数流行病学研究评估了PM2.5化学成分与呼吸系统疾病之间的关系。大多数评估受到环境PM测量的时空分辨率不足和/或其检查特定PM成分对健康结果作用的方法的限制。在一项病例交叉分析中，我们使用从社区多尺度空气质量（CMAQ）模型和现有观测数据得出的每日平均环境PM2.5总质量和物种估计值，研究了纽约州PM的化学成分（包括元素碳和有机碳、硫酸盐、硝酸盐、铵以及其他剩余成分）与呼吸系统住院之间的关联。我们评估了PM成分质量分数水平（低、中、高）之间的关系，并通过按一次和二次PM成分质量分数分层的模型评估了PM2.5与住院关联的修正情况。在我们的结果中，纽约州的每日平均PM2.5浓度总体上低于24小时平均国家环境空气质量标准（NAAQS）。全年分析显示，在多个暴露滞后时间（每四分位数间距[IQR]增加0.5 - 2.0%），呼吸系统住院与PM2.5总质量、硫酸盐、硝酸盐和铵浓度之间存在统计学上显著的正相关。主要在夏季，在滞后1 - 4天（1.0 - 2.0%）时，每IQR增加二次物种硫酸盐和铵浓度与呼吸系统住院的关联最为明显。尽管在质量分数三分位数之间观察到的关联存在细微差异，但没有有力证据支持特定成分对PM2.5与呼吸系统疾病关联的修正作用。我们得出结论，尽管模式因季节而异，但环境中PM2.5以及包括硫酸盐、铵和硝酸盐在内的二次气溶胶浓度与呼吸系统住院呈正相关。接触特定的细颗粒物成分是纽约州呼吸系统住院的一个合理风险因素。
仅有少数具有精细时空尺度数据的流行病学研究评估了环境中PM2.5成分浓度之间的关联。在纽约州，细颗粒物及其几种成分，包括硫酸盐、铵和硝酸盐，与呼吸系统住院呈正相关。结果表明，PM物种关系及其对呼吸终点的影响是复杂且依赖季节的。需要开展更多工作以更好地理解PM物种的相对毒性，并进一步探索共污染物关系和暴露预测误差对观察到的PM与呼吸系统疾病关联的作用。
