Oil and gas emissions, health research suggests pollution standards are inadequate

April 11-- Apr. 11--A paper published this month suggests recent air quality study models and pollution level recommendations are inadequate to gather appropriate data to inform policy or explain unhealthy symptoms in people living near active oil and gas development.

The paper in the Annual Review of Public Health was written by California and New York researchers and included analysis of 37 peer-reviewed journal articles on oil and gas emissions published between 2012 and February 2018, several of which studied extraction site data measured on Colorado'sFront Range. Data observed in seven other states and Poland also was reviewed.

Because recommended safe limits for individual air pollutants are usually set by accounting for health risks caused by exposure to just one substance at a time, standards might need to become more stringent to protect people against impacts that are possibly worsened and expedited by contact with and ingestion of multiple substances simultaneously and over time, which is possible near drilling, the paper states.

"We don't have much research on what happens when you're exposed to a cocktail of pollutants," said Diane Garcia-Gonzales, an author of the paper and researcher at the University of California, Los Angeles Institute of Environment and Sustainability.

"I think using the methods that we've used in the past to understand impact, which is basing ambient air quality concentrations of a single pollutant and comparing it to a health-based standard, would be inadequate and misleading to describe health effects potentially associated with extraction," she said. "I think there is something bigger going on."

Fracking not most risky stage?

The paper also concluded that hazardous air pollutants -- for which there are no regulatory standards, but only recommended thresholds to avoid exposure to, according to a Colorado researcher -- are associated at possibly dangerous levels with the production phase of oil and gas development, and not just the fracking stage, as commonly thought.

"Hydraulic fracturing has received the greatest attention for its potential impact to human and environmental health," the paper stated. "In the context of hazardous air pollutants, however, we did not find evidence to support the common assumption that the discrete hydraulic fracturing phase itself is associated with the highest risk of exposure."

Instead, the paper said, the production phase of oil and gas, or the actual harvesting of underground minerals, involves the largest number of air pollutants that could be emitted and has the potential to spew the highest concentrations and most varied mixtures of pollutants over the longest time period -- wells can remain productive for years.

Even the storage phase for energy mined and wastewater once used to access it has a chance of exposing people to harmful contaminants, the paper stated.

"Our review of the literature further suggests that exposure risks can be much higher if production equipment is co-located with condensate storage and wastewater impoundments," the paper stated.

Pollutants together might speed signs of symptoms

It also noted there is a spatial correlation between people's unhealthy symptoms and oil and gas development sites, even though pollutant concentrations captured near operations often measure below health benchmarks.

The reason for that is unclear, the paper stated, but it suggested current sampling methods for pollutants near oil and gas sites might "fail to capture the episodic peak emission events characteristic of upstream oil and natural gas" development, and that "prevailing health benchmarks are inadequate to identify exposures to chronic, low levels of pollutants, multiple chemical exposures or from multiple exposure pathways."

That means plans for measuring extraction-caused pollution and associated health effects haven't fully accounted for emissions volumes from oil and gas varying day to day, and even hour to hour, and that pollutants might actually be harmful in amounts below the recommended safe levels when other contaminants also are being emitted near people, or through multiple mediums, such as through the soil, groundwater and air.

So how can science that could guide regulations and recommendations for healthy living catch up to consider these factors?

Colorado School of Public Health Assistant Research Professor Lisa McKenzie -- who led a controversial study published last year that found cancer risk for people living within 500 feet of oil and gas operations significantly exceeds California limits -- said catch-up could be a lengthy and costly process.

That's because there are some substances emitted at oil and gas sites for which there are currently no reference exposure levels officials recommend to avoid, she said.

"Getting reference exposure levels for the chemicals we don't have them for right now would take doing laboratory experiments with animals," McKenzie said. "Those take time and are quite expensive."

But trying to quantify the variance of emissions for contaminants with established levels that affect human health should be undertaken in the meantime, she said.

"I would think one place to start is to actually do more monitoring around these sites to know what the ambient concentrations in the air are and how they're varying, and how often they do exceed these recommended exposure levels that we have," McKenzie said.

Sam Lounsberry: 303-473-1322, slounsberry@prairiemountainmedia.com and twitter.com/samlounz.

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