Air Pollution

Research Report 193 describes a novel study by Jiu-Chiuan Chen and colleagues examining possible associations between long-term exposure to ambient particulate matter (PM) and changes in the brains of older women in the United States. The study focused on brain volumes and neurocognitive outcomes, specifically mild cognitive impairment and dementia. Dr. Chen used neuroimaging and cognitive outcome data from women enrolled in the Women’s Health Initiative Memory Study and estimated their exposure to ambient PM_2.5 and to diesel PM.

Research Report 191 describes a study by Allison Fryer and colleagues that addressed how exposure to ozone affects the immune and physiological responses in guinea pigs. In her study, Dr. Fryer focused on eosinophils, white blood cells that play an important role in inflammation, allergies, and allergic asthma, and can modify the airway response to ozone inhalation. This study tested a novel hypothesis: that allergic guinea pigs react differently to ozone than normal animals because of newly formed eosinophils that migrate from bone marrow to the lungs.

Research Report 190 describes a study by Frank Gilliland and colleagues that was funded under HEI’s Accountability research program. The investigators collected air quality data and lung function and respiratory symptoms in three cohorts of children who participated in the Children’s Health Study in Southern California. During the 20-year study period, nearly 20 major policy actions were implemented to reduce pollution from transportation and other sources. Gilliland and colleagues evaluated whether the improved air quality was associated with improved lung function and respiratory symptoms in these children.

HEI Research Report 189 describes a study by Dr. Zhengmin Qian conducted in Wuhan, the capital city of Hubei province in China. Wuhan experiences temperature extremes and generally has higher air pollution levels than those seen in the United States and Europe. Dr. Qian examined whether increased exposures to air pollutants (particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone) during vulnerable pregnancy periods were associated with increased rates of preterm birth, low birth weight, or intrauterine growth retardation, using both a cohort and nested case-control design.