Relative Contributions of PM_2.5Chemical Constituents to Acute Arterial Vasoconstriction in Humans

Abstract

Studies have shown associations between acute ambient particulate matter (PM) levels and increases in morbidity and mortality from cardiovascular diseases. We have previously reported in 24 healthy adults that exposure to concentrated ambient particles plus ozone (CAP + O(3)) caused a mean decrease of 0.09 mm in brachial artery diameter (BAD), which was significantly larger than a mean increase of 0.01 mm among the same individuals exposed to filtered air (FA). Our current objective is to examine the relationship between total and constituent PM(2.5) mass concentrations and the acute vascular response. We have analyzed both ambient and exposure filters from the brachial artery study for major chemical constituents, allowing us to compare the strength of the associations between each constituent and an individual's arterial response. We determined gravimetric PM(2.5) mass concentration and inorganic ion content from exposure filters. Twenty-three-hour ambient PM(2.5) filters collected from the same site and on the same day were used to estimate exposure concentrations of trace elements and organic and elemental carbon. We performed linear regression analyses on the levels of measured or estimated PM constituents using each subject's FA exposure as a control. We found, from our regression analyses, a significant negative association between both the organic and elemental carbon concentrations and the difference in the postexposure change in the BAD (Delta BAD) between and CAP + O(3) and FA exposure days. An understanding of the PM constituents most responsible for adverse health outcomes is critical for efforts to develop pollution abatement strategies that maximize benefits to public health.

Particulate Matter Air Pollution and Cardiovascular Disease

“…The magnitude of response was associated with the concentration of organic carbon within PM 2.5 . 405 Recent follow-up studies redemonstrated an acute prohypertensive response during the inhalation of CAP in 2 separate cities. 390 The PM 2.5 mass during exposure and decreases in several HRV metrics were associated with the magnitude of the short-lived diastolic BP elevation.…”

Particulate Pollution and Endothelial Function

“…It is conceivable that traffic-related sources and subfractions may still play an important role in modulating vessel wall responses. 5 How might PM modulate endothelial function? Loss of endothelium-derived nitric oxide ( · NO) plays a central role in the pathogenesis of diseases such as smoking-related vascular disease, atherosclerosis, hypertension, and diabetes.…”

A Study on the Source Profile Development for Diesel and Gasoline-Powered Vehicles

“…자동차에서 배출되는 오염물질들은 급성 및 만성 심혈관질환과 호흡기질환을 포함하여 인체에 악영향 을 미치고 있다 (Urch et al, 2004;Garshick et al, 2003;Brunekreef et al, 1997 (Jerrett et al, 2005;Sun et al, 2005;Somers et al, 2004;Pope et al, 2002;Burnett et al, 1995;Dockery et al, 1993). 디젤자동차나 가솔린자동차에서 배출되는 미세먼 지가 도시대기 중에서 차지하는 비율이 상당히 높은 것으로 알려져 있다 (Kang et al, 2008).…”