The mortality associated with exposure to PM2.5 and NO2 has long been described, but few studies have used causal modeling methods that can help moving from statistical association to causal inference. Researchers at the Harvard/MIT ACE Center used three different methods to estimate the causal effect of local pollution on mortality in 135 US cities. Read More
Tag: PM2.5
Air pollution and chronic bronchitis
Air pollution exposure was found to be associated with chronic bronchitis (chronic cough and sputum production) in a recent study by researchers at the University of Washington. The study was conducted on the large Sisters Study cohort (about 50,000 participants), limiting analysis to never-smokers, and using exposure models to PM10, PM2.5, and NO2 developed for Read More
Summertime air quality and climate oscillations
Long-period atmospheric oscillations can have effects on summertime air quality in the Eastern US, based on two studies from Harvard researchers, and these effects can be relevant to air quality management. The first analysis shows that summertime air quality in the eastern US depends on the sea-surface temperature in the North Atlantic Ocean. Researchers used observations Read More
Indoor effects of wildfires
Wildfire events can significantly increase indoor PM2.5 and VOCs, based on work by researchers at Washington State University. In a detailed analysis of air exchanges between indoor and ambient air, during and outside of wildfire events, researchers examined the indoor and outdoor concentrations of fine particles, ozone, and a number of VOCs in two test Read More
Short-term exposure to air pollution: mortality without threshold
Short-term exposure to PM2.5 and ozone were significantly associate with mortality risk without evidence of a threshold, in a study on the entire Medicare population. Researchers at the Harvard/MIT ACE center examined all-cause mortality risk associated with same-day and prior day exposure to PM2.5 and ozone (adjusting for simultaneous exposure) in a case-crossover design applied Read More
Factors in PM2.5 mortality
Numerous factors affect the association between PM2.5 and mortality, including individual and neighborhood socioeconomic status, PM composition and temperature. In a study of 13 million Medicare beneficiaries (older than 65) conducted in the SouthEastern US, researchers at the Harvard ACE Center examined exposures using a hybrid spatio-temporal model that represented more accurately rural populations and Read More
Air pollution and HDL cholesterol
Exposure to black carbon and PM2.5 was found to be associated with lower measures of desirable HDL cholesterol in a paper based on the Multi-ethnic Study of Atherosclerosis (MESA) cohort. As a part of the MESA Air study led by the University of Washington, investigators examined the association of PM2.5 and black carbon exposures with Read More
Wildfires and respiratory hospitalization
Exposure to wildfire-specific PM2.5 was associated with increased respiratory hospitalization. In a study with the Medicare population in the Western United States, researchers from the Harvard Clean Air Research Center estimated exposures to wildfire-specific PM2.5 using a global chemical transport model, between 2004 and 2009. About 5 million Medicare participants were exposed to at least Read More
PM2.5 effects below standards
Exposure to PM2.5 at level near or below existing National Ambient Air Quality Standards was associated with increased hospital admissions in a population of Medicare enrollees. Analyzing records of 32,119 people in 5,138 ZIP codes in the Medicare Current Beneficiary Survey between 2002 and 2010, researchers part of the Harvard ACE Center found that average Read More
Indoor air and “smart homes”
Human behavior inside a home strongly affects indoor air quality, based on a study in sensors-rich “smart homes” environments. Researchers at Washington State University measured air pollutants (PM, ozone, CO2, and 13 organic compounds) inside two home fitted with a variety of sensors to detect human presence and activities, such as motion, ambient light, window Read More