Associations between personal exposures to VOCs and alterations in cardiovascular physiology: Detroit Exposure and Aerosol Research Study (DEARS)
- DOI
- Language of the publication
- English
- Date
- 2015-01-06
- Type
- Article
- Author(s)
- Shin, Hwashin Hyun
- Jones, Paul
- Brook, Robert
- Bard, Rob
- Oliver, Karen
- Williams, Ron
- Publisher
- Elsevier
Abstract
Background An adult cohort consisting of 63 participants engaged in the US EPA's recent Detroit Exposure and Aerosol Research Study (DEARS) and a University of Michigan cardiovascular sub-study conducted during summer and winter periods over 3 years between 2004 and 2007 (5 seasons in total). Through all participants' wearing of a monitoring vest, personal exposures to various air pollutants were measured. Purpose The study objective was to identify the association between personal exposure to volatile organic compounds (VOCs) and six cardiovascular health endpoints in an adult non-smoking cohort of the DEARS. Methods Twenty five VOCs were collected using the DEARS exposure vest incorporating advanced passive diffusion tube. Six cardiovascular health endpoints including systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), brachial artery diameter (BAD), brachial artery flow-mediated dilatation (FMD) and nitroglycerin-mediated arterial dilatation (NMD) were collected by novel, in-home clinical examinations. To reduce the number of personal VOCs highly correlated to each other, a principal component analysis was conducted. Accounting for more individual variations in association between personal VOCs and cardiovascular health endpoints, a linear mixed model was employed, where cohort subjects were not necessarily to have the same linear association. Results Applying the principal component analysis, 3 out of 12 components were retained, which appeared to involve a petroleum source (1st component), a 1-3 butadiene source (2nd component), and an ambient (Freon) source (3rd component). Petroleum related VOCs were associated with increases in FMD and showed mixed relationships with NMD (lag 0–1 day increased NMD, lag 2 days decreased NMD). Butadiene related VOCs decreased DBP but increased HR and BAD. Freon (ambient background) related VOCs increased HR. Conclusions We observed mixed and variable results in this first study to evaluate the relationships between personal exposures to VOCs of different origin on cardiovascular physiology. In sum, the findings suggest that VOCs may have rapid impacts upon the human cardiovascular system; however, understanding the health implications and the mechanisms responsible is beyond the scope of this investigation.
Plain language summary
Volatile organic compounds (VOCs) are found in indoor and outdoor air. They arise from multiple sources and have a wide range of potential health effects. Identifying their contribution to air pollution related illness in non-occupational settings is complicated by difficulties in identifying sources and in accurately evaluating exposure. In addition, statistical analyses show the concentrations of the different chemicals to be highly related to one another, limiting the potential to use epidemiological analyses to associate specific pollutants with health effects. The Detroit Exposure and Aerosol Research Study (DEARS) has proven to be a valuable source of data useful in defining the variation in urban air pollution with time and location. It has examined how humans are exposed to various pollutants in many situations, and studied the impact of these exposures sources upon observable health effects. This study made use of DEARS data on personal exposure of 63 non-smoking subjects to 25 VOCs, and related this data to measurements of six indicators of cardiovascular health (systolic and diastolic blood pressure, heart rate, brachial artery diameter, brachial artery flow-mediated dilatation and nitroglycerin-mediated arterial dilatation). Using statistical methods, the VOCs were combined into three uncorrelated groups, which were then used to relate to health endpoints. While the three groups of VOCs were associated with some of the six cardiovascular health outcomes, they may operate via different biological mechanisms, which remain unknown. These results suggest that VOCs may have rapid impacts upon the human cardiovascular system; however, understanding the health implications and the mechanisms responsible require additional investigations. These results broaden the understanding of the relationship between air pollution and cardiovascular disease, will be useful in assessments of the health impacts of air pollution, and provide a new methodology for additional studies that relate VOC exposure to health. This study was led by the US Environmental Protection Agency and involved scientists from Queen's University and the University of Michigan, in addition to Health Canada.
Subject
- Health,
- Health and safety