ADVERTISEMENT

Using High-Resolution Metabolomics To Study The Effects Of Air Traffic Pollution

Published by Donghai Liang

Rollins School of Public Health, Emory University, Atlanta, USA

These findings are described in the article entitled Use of high-resolution metabolomics for the identification of metabolic signals associated with traffic-related air pollution, recently published in the journal Environment International (Environment International 120 (2018) 145-154). This work was conducted by Donghai Liang, Tianwei Yu, Chandresh N. Ladva, Douglas I. Walker, Stefanie Ebelt Sarnat, Howard H. Chang, Dean P. Jones, and Jeremy A.Sarnat from Emory University, Jennifer L. Moutinho and Armistead G. Russell from the Georgia Institute of Technology, Rachel Golan from the Ben-Gurion University of the Negev, Megan Niedzwiecki from the Icahn School of Medicine at Mount Sinai, and Howard H. Chang and Roby Greenwald from the Georgia State University School of Public Health. Funding was provided by Health Effects Institute and the HERCULES exposome research center, supported by the National Institute of Environmental Health Sciences of the National Institutes of Health (P30ES019776).

Due to the fast development of urbanization and the increasing number of vehicles on the road, traffic emissions has become one of the major sources for ambient pollution everywhere around the globe. In the United States, where traffic emissions account for around a quarter of the ambient air pollution, more than 45 million residents live within 100 meters of a four-lane highway.

ADVERTISEMENT

Accurately assessing exposures to traffic-related pollution is particularly critical, given the abundance of observational and controlled studies reporting associations between traffic sources and numerous adverse health effects. However, measuring internal, biologically-relevant exposures and corresponding health effects associated with traffic emissions remain very challenging, due to the individual susceptibility, impact of the pre-existing condition, and complexity of numerous endogenous pathways that may mediate the responses. In particular, the specific biological factors and pathways, as well as how they respond upon exposure to traffic pollution mixture are poorly understood.

With the advancement in the omics-based technologies, high-resolution mass spectrometry coupled with liquid chromatography, an analytical platform capable of quantifying thousands of exogenous toxicants and endogenous metabolites, has emerged as a powerful tool to improve internal exposure estimation to complex environmental mixtures. To test whether high-resolution metabolomics can identify specific metabolic indicators of primary traffic pollution with sufficient sensitivity and robust signals, a research team led by scientists from Emory University conducted the Dorm Room Inhalation to Vehicle Emission (DRIVE) study, an intensive 12-week filed study that focused on assessing a complete emission-to-exposure pathway of primary traffic pollution.

Credit: Donghai Liang

During the DRIVE study period, a suite of traffic-related pollutants was measured at multiple ambient and indoor sites at varying distances from a major highway artery. In parallel, 54 college students living in dormitories near (20 m) or far (1.4 km) from the highway contributed weekly plasma and saliva samples. Untargeted Metabolome-Wide Association Study (MWAS) workflow, where metabolic profiles were analyzed without prior knowledge of their chemical identity, was applied to assess associations between metabolic feature intensity (i.e., relative concentration) and levels of traffic-related pollutants. Finally, comprehensive pathway analysis and chemical validation were conducted to identify specific metabolic patterns and to further investigate potentially biologically relevant indicators to primary traffic exposures.

The study reported that 1,291 unique metabolic features were significantly associated with at least one or more traffic indicator, including black carbon, carbon monoxide, nitrogen oxides, and fine particulate matter, after controlling for confounding and false discovery rate. Pathway analysis of metabolic features associated with traffic exposure indicated elicitation of inflammatory and oxidative stress-related pathways, including leukotriene and vitamin E metabolism. In addition, chemical identities of 10 metabolites associated with traffic pollutants were confirmed, including arginine, histidine, ő≥-linolenic acid, and hypoxanthine.

ADVERTISEMENT

The results from this study further support high-resolution metabolomics as a powerful platform for elucidating biologically relevant pathways associated with exposures to key environmental pollutants and sources. Observed response was consistent with endogenous metabolic signaling related to oxidative stress, inflammation, and nucleic acid damage and repair. Collectively, the current findings in this study provide support for the use of untargeted high-resolution metabolomics in the development of metabolic biomarkers of traffic pollution exposure and response. While highly intriguing, these findings warrant replication to solidify their use as novel, specific indicators of exposure and response to this critical source of urban air pollution.

Comments

READ THIS NEXT

Sophisticated Family Planning In Malaria Parasites

Malaria parasites can tell good times from bad times and plan their offspring accordingly. The reproductive strategy these disease-causing parasites […]

Elevated Temperature And Lower Ocean pH May Limit Larval Supply In The Florida Stone Crab

Many coastal watersheds have suffered from decades of urbanization which has diverted stormwater, carrying nutrient pollution, into coastal ocean waters. […]

Pulmonary Artery Catheterization Use And Mortality In Heart Failure Patients  

The current study is the first to show that the use of pulmonary artery catheterization (PAC) declined from 2005 to […]

Vanishing Air-Bubble Layer And Ion Adsorption On Graphene In Aqueous Media

Potential applications of graphene in bioanalytic devices and functional composites have recently attracted wide attention. For these applications, graphene often […]

Can Cultivation Be Part Of A No-Till Farming System?

Farmers in Australia‚Äôs northern grain growing regions embraced no-till farming decades ago to preserve scarce soil moisture, reduce the risk […]

Clustering By Shared Subspaces: A New Framework For Data Analysis

Clustering is a fundamental data analysis technique with applications in engineering, medical and biological sciences, social sciences, and economics. For […]

Properties Of Metalloids For Chemistry Class

Metalloids are also sometimes referred to as semimetals, owing to the fact that metalloids have properties which are in-between metals […]

Science Trends is a popular source of science news and education around the world. We cover everything from solar power cell technology to climate change to cancer research. We help hundreds of thousands of people every month learn about the world we live in and the latest scientific breakthroughs. Want to know more?