The oil and gas sector got some good news earlier this spring when the province released a comprehensive human health risk assessment of industry activities in northeast B.C.
The study, commissioned two years earlier in response to concerns raised by residents in the Fort St. John region, found the adverse effects from exposure to an array of "chemicals of potential concern" weren't significant.
"Overall, long-term inhalation exposures to the COPC were predicted to be associated with a low potential for adverse health effects," concluded Intrinsik Environmental Sciences Inc., which did the study for the B.C. Ministry of Health.
The report must have come as a relief to people who live in the northeast, where more than 18,000 gas wells have been drilled to date, and where more wells are planned.
But there is now reason to think the air isn't quite as safe as it seemed in March when the Intrinsik report came out.
A new study by two U.S. universities has found the impact of natural-gas extraction on the levels of polycyclic aromatic hydrocarbons (PAHs) in the air is a health concern.
A team from Oregon State University and the University of Cincinnati worked with rural landowners in Carroll County, Ohio, to record air quality over several weeks at 23 locations outside city limits and away from potential PAH sources such as roads, airports and chimneys.
What they found was surprising and, given the explosion of natural-gas wells in northeast British Columbia, of some concern.
Out there in rural Carroll County, where there are only about 400 gas wells, the researchers found PAH levels higher than in downtown Chicago.
"Air pollution from fracking operations may pose an under-recognized health hazard to people living near them," the study's co-author, Kim Anderson, an environmental chemist with Oregon State University's College of Agricultural Sciences, said in a statement.
The study found PAH levels were consistently higher closer to gas wells and for the worst-case scenario – exposure 24 hours a day over 25 years – the pollutants were at levels greater than the Environmental Protection Agency considers safe for cancer.
"This work suggests that natural-gas extraction may be contributing significantly to PAHs in the air, at levels that are relevant to human health," states the study.
The research notes that natural-gas extraction techniques aren't the same everywhere, however, meaning it is "possible that these differences could impact PAH emissions, and thus that these results may not be directly applicable to other regions."
When the B.C. Ministry of Health was asked to comment on the U.S. study, which appears to contradict the provincial findings, the government seized on that qualifying statement as a possible explanation.
"This [U.S.] study focused on air samples collected from sites in Carroll County in Ohio, not B.C.," stated the ministry in an e-mail. "The [U.S.] study does state that its findings may not be pertinent to other gas-producing areas because PAH emissions are influenced by extraction techniques and by underlying geology."
The ministry also said protecting the health of British Columbians "is one of our government's top priorities," and air quality is being monitored throughout the province.
But B.C. hasn't done the PAH study that was done in the U.S. and provincial officials are assuming leaky gas wells in the northeast somehow are less of a cancer risk than leaky gas wells in Ohio.
Calvin Sandborn, legal director for the University of Victoria Environmental Law Centre, doesn't think that's wise and says the U.S. findings should be ringing alarm bells in B.C.
"This is objective science," he said of the U.S. research. "I just wish these people had done the health study for the province instead of Intrinsik. If I was a resident in northeast British Columbia, I'd like to see these people from Oregon State University and the University of Cincinnati doing a study here."
If nothing else, the U.S. findings should persuade the Ministry of Health that it needs to do more research. Passive air samplers, set up near gas wells in northeast B.C. and monitored by residents as they were in Ohio, would be a good start.
Mark Hume