Mortality and indicators of traffic-related air pollution

There is increasing evidence linking long-term fine particulate matter (PM 2.5 ) exposure to negative health effects. However, the relative influence of each component of PM 2.5 on health risk is poorly understood. In a cohort study in the contiguous United States between 2000 and 2017, we examined the effect of long-term exposure to PM 2.5 main components and allcause mortality in older adults who had to be at least 65 years old and enrolled in Medicare. We estimated the yearly mean concentrations of six key PM 2.5 compounds, including black carbon (BC), organic matter (OM), soil dust (DUST), nitrate (NO 3 − ), sulfate (SO 4 2−), and ammonium (NH 4 + ), using two independently sourced well-validated prediction models. We applied Cox proportional hazard models to evaluate the hazard ratios for mortality and penalized splines for assessing potential nonlinear concentration−response associations. Results suggested that increased exposure to PM 2.5 mass and its six main constituents were significantly linked to elevated all-cause mortality. All components showed linear concentration−response relationships in the low exposure concentration ranges. Our research indicates that long-term exposure to PM 2.5 mass and its essential compounds are strongly connected to increased mortality risk. Reductions of fossil fuel burning may yield significant air quality and public health benefit.

Section: ■ Discussionmentioning

confidence: 99%

National Cohort Study of Long-Term Exposure to PM_2.5 Components and Mortality in Medicare American Older Adults

Hao

Wang

Zhu

et al. 2023

“…Exposure to traffic-related air pollution (TRAP) has been associated with increased morbidity and mortality. Health effects including wheeze, cough, sputum production, other asthmarelated symptoms, 1−7 impaired lung function, 8,9 increased heart rate variability, 5,10 and increased mortality 11,12 have been reported. Recently there have been reports of lower birth weight in the offspring of mothers heavily exposed to TRAP.…”

Section: ■ Introductionmentioning

confidence: 99%

Redistribution of Traffic Related Air Pollution Associated with a New Road Tunnel

Cowie

Rose

Gillett

et al. 2012

The aim of this study was to assess the effect of a new road tunnel on the concentration and distribution of traffic-related air pollution (TRAP), specifically nitrogen dioxide (NO(2)) and particulate matter (PM), and to determine its relationship to change in traffic flow. We used continuously recorded data from four monitoring stations at nonroadside locations within the study area and three regional monitors outside the area. The four monitors in the study area were in background locations where smaller pollutant changes were expected compared with changes near the bypassed main road. We also deployed passive samplers to assess finer spatial variability in NO(2) including application of a land use regression model (LUR). The study was conducted from 2006 to 2008. Analysis of the continuously recorded data showed that the tunnel intervention did not lead to consistent reductions in NO(2) or PM over the wider study area. However, there were significant decreases in NO(2), NO(x), and PM(10) in the eastern section of the study area. Analysis of passive sampler data indicated that the greatest reductions in NO(2) concentrations occurred within 100 m of the bypassed main road. The LUR model also demonstrated that changes in NO(2) were most marked adjacent to the bypassed main road. These findings support the use of methods that highlight fine spatial variability in TRAP and demonstrate the utility of traffic interventions in reducing air pollution exposures for populations living close to main roads.

“…Living near heavily trafficked roadways poses severe health risks. Epidemiological studies have associated living near roadways with a wide range of diseases and adverse health indicators including low birth weight, 1 preterm birth, 2 breast cancer, 3 childhood central nervous system tumors, 4 childhood leukemia, 5 asthma, 6 reduced lung function, 7 myocardial infarction, 8 atherosclerosis, 9 Parkinson's disease, 10 autism spectrum disorder (ASD), 11,12 dementia, 13,14 and Alzheimer's disease (AD). 15,16 As populations worldwide are increasingly concentrated in urban areas, the number of people exposed to traffic-related air pollution (TRAP) increases with concomitant concern for the health effects associated with such exposures.…”

Section: ■ Introductionmentioning

confidence: 99%

Emulating Near-Roadway Exposure to Traffic-Related Air Pollution via Real-Time Emissions from a Major Freeway Tunnel System

Bein

Wallis

Silverman

et al. 2022

Epidemiological and toxicological studies continue to demonstrate correlative and causal relationships between exposure to traffic-related air pollution and various metrics of adverse pulmonary, cardiovascular, and neurological health effects. The key challenge for in vivo studies is replicating real-world, near-roadway exposure dynamics in laboratory animal models that mimic true human exposures. The advantage of animal models is the accelerated time scales to show statistically significant physiological and/or behavioral response. This work describes a novel exposure facility adjacent to a major freeway tunnel system that provides a platform for real-time chronic exposure studies. The primary conclusion is that particulate matter (PM) concentrations at this facility are routinely well below the National Ambient Air Quality Standards (NAAQS), but studies completed to date still demonstrate significant neurological and cardiovascular effects. Internal combustion engines produce large numbers of ultrafine particles that contribute negligible mass to the atmosphere relative to NAAQS regulated PM2.5 but have high surface area and mobility in the body. It is posited here that current federal and state air quality standards are thus insufficient to fully protect human health, most notably the developing and aging brain, due to regulatory gaps for ultrafine particles.