Respiratory hospitalizations in association with fine PM and its components in New York State
Creators: name: Jones, Rena R.
name: Hogrefe, Christian
name: Fitzgerald, Edward F.
name: Syni-An Hwang
name: Halûk Özkaynak
name: Garcia, Valerie C.
name: Lin, Shao
Publisher: name: Taylor & Francis
Year: 2015
Subjects: Cancer
Biological Sciences
Chemistry
Earth and Environmental Sciences
Biotechnology
Medicine

description: ABSTRACT<b>Background:</b> Despite observed geographic and temporal variation in PM-related health morbidities, only a small number of epidemiologic studies have evaluated the relation between PM<sub>2.5</sub> 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.<b>Methods:</b> In a case-crossover analysis using daily average ambient PM<sub>2.5</sub> 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 PM<sub>2.5</sub>- hospitalization association via models stratified by mass fractions of both primary and secondary PM components.<b>Results:</b> Average daily PM<sub>2.5</sub> concentrations in New York State were generally lower than the National Ambient Air Quality (NAAQS) 24-hour average concentration standard. Year-round analyses showed statistically significant positive associations between respiratory hospitalizations and PM<sub>2.5</sub> total mass, sulfate, nitrate, and ammonium concentrations at multiple exposure lags (0.5-2% per IQR increase). Primarily in the summer months, the greatest risks of 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 PM<sub>2.5</sub>-respiratory disease association by a particular constituent.<b>Conclusions:</b> Ambient concentrations of PM<sub>2.5</sub> 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. IMPLICATIONSThe association between ambient concentrations of PM<sub>2.5</sub> 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.