Ambient Nonmethane Hydrocarbon Levels Along Colorado’s Northern Front Range: Acute and Chronic Health Risks

Abstract

Oil and gas (O&G) facilities emit air pollutants that are potentially a major health risk for nearby populations. We characterized prenatal through adult health risks for acute (1 h) and chronic (30 year) residential inhalation exposure scenarios to nonmethane hydrocarbons (NMHCs) for these populations. We used ambient air sample results to estimate and compare risks for four residential scenarios. We found that air pollutant concentrations increased with proximity to an O&G facility, as did health risks. Acute hazard indices for neurological (18), hematological (15), and developmental (15) health effects indicate that populations living within 152 m of an O&G facility could experience these health effects from inhalation exposures to benzene and alkanes. Lifetime excess cancer risks exceeded 1 in a million for all scenarios. The cancer risk estimate of 8.3 per 10 000 for populations living within 152 m of an O&G facility exceeded the United States Environmental Protection Agency's 1 in 10 000 upper threshold. These findings indicate that state and federal regulatory policies may not be protective of health for populations residing near O&G facilities. Health risk assessment results can be used for informing policies and studies aimed at reducing and understanding health effects associated with air pollutants emitted from O&G facilities.

Climate and health benefits of increasing renewable energy deployment in the United States*

“…Health impacts of coal mining can make up a substantial portion of the total impacts of coal [39][40][41]. Health impacts related to proximity to natural gas wells were not included here [42][43][44]. Assessing the impacts of stack emissions from power plants, as in our main analysis, substantially underestimates the total benefits from RE, by omitting the benefits of reducing consumption of fossil fuels.…”

Air Monitoring Stations Far Removed From Drilling Activities Do Not Represent Residential Exposures to Marcellus Shale Air Pollutants. Response to the Paper by Hess et al. on Proximity-Based Unconventional Natural Gas Exposure Metrics

“…The epidemiological studies that have used the proximity WA or similar models have all observed the greatest health implications in the densest areas of O&G well activity, generally at residences within 20 km of a well [2,[4][5][6][7][8][9][10][11][12][13][14][15]. McMullin et al (2018) recently evaluated air pollution measured from monitors at distances from O&G wells ranging from 0.1 km to 1.13 km to the closest O&G site and found a number of VOCs, notably benzene, ethylbenzene, and n-nonane [16].…”

Synthesis and health-based evaluation of ambient air monitoring data for the Marcellus Shale region

“…Recent integrative assessments have been conducted for other shale plays (e.g., for the Barnett Shale region in Texas [Bunch et al 2014] and the Niobrara Shale region in Colorado [CDPHE 2017;McMullin et al 2018;McKenzie et al 2018]), but we are not aware of such a broad assessment of air quality data for the Marcellus Shale region, despite a substantial increase in the amount of ambient air monitoring data collected nearby to Marcellus Shale development activities. Given that the available air quality data are currently scattered among different databases and studies, the objective of this assessment was thus to assemble the body of data and provide an integrative screening-level assessment of its implications for air-related public health impacts of OGD activities in the Marcellus Shale region.…”

“…These include both criteria air pollutants (fine particulate matter [PM 2.5 ], nitrogen dioxide [NO 2 ], sulfur dioxide [SO 2 ]), U.S. EPA hazardous air pollutants (HAPs; acetaldehyde, benzene, ethylbenzene, formaldehyde, n-hexane, toluene, and xylenes), and hydrogen sulfide (H 2 S). Some of the few available quantitative risk assessments conducted for shale play regions have reported findings suggesting that these air pollutants may be associated with the greatest potential for human health risks (CDPHE 2017;McKenzie et al 2018McKenzie et al , 2012McMullin et al 2018). We did not include the major natural gas constituents (methane, ethane, propane, butane) in our assessment because they are of low direct toxicity to humans (Goldstein et al 2014;McKee et al 2014).…”