Toxicological research suggests that coarse particles (PM10–2.5) are inflammatory, but responses are complex and may be best summarized by multiple inflammatory markers. Few human studies have investigated associations with PM10–2.5 and, of those, none have explored long-term exposures. Here we examine long-term associations with inflammation and coagulation in the Multi-Ethnic Study of Atherosclerosis.
Participants included 3,295 adults (45–84 years of age) from three metropolitan areas. Site-specific spatial models were used to estimate 5-year concentrations of PM10–2.5 mass and copper, zinc, phosphorus, silicon, and endotoxin found in PM10–2.5. Outcomes included interleukin-6, C-reactive protein, fibrinogen, total homocysteine, D-dimer, factor VIII, plasmin–antiplasmin complex, and inflammation and coagulation scores. We used multivariable regression with multiply imputed data to estimate associations while controlling for potential confounders, including co-pollutants such as fine particulate matter.
Some limited evidence was found of relationships between inflammation and coagulation and PM10–2.5. Endotoxin was the PM10–2.5 component most strongly associated with inflammation, with an interquartile range (IQR) increase (0.08 EU/m3) associated with 0.15 (95% CI: 0.01, 0.28; p = 0.03) and 0.08 (95% CI: –0.07, 0.23; p = 0.28) higher inflammation scores before and after control for city, respectively. Copper was the component with the strongest association with coagulation, with a 4-ng/m3 increase associated with 0.19 (95% CI: 0.08, 0.30; p = 0.0008) and 0.12 (95% CI: –0.05, 0.30; p = 0.16) unit higher coagulation scores before and after city adjustment, respectively.
Our cross-sectional analysis provided some evidence that long-term PM10–2.5 exposure was associated with inflammation and coagulation, but associations were modest and depended on particle composition.
Adar SD, D’Souza J, Mendelsohn-Victor K, Jacobs DR Jr, Cushman M, Sheppard L, Thorne PS, Burke GL, Daviglus ML, Szpiro AA, Diez Roux AV, Kaufman JD, Larson TV. 2015. Markers of inflammation and coagulation after long-term exposure to coarse particulate matter: a cross-sectional analysis from the Multi-Ethnic Study of Atherosclerosis. Environ Health Perspect 123:541–548; http://dx.doi.org/10.1289/ehp.1308069