A study led by the University of California-Irvine found higher levels of air pollutants in a rural area near Canada's largest oil, gas and tar sand processing areas than in some of the most polluted cities in the world. Men living in this rural area also show higher rates of cancers known to be linked to the contaminants.
In a recent online issue of Atmospheric Environment, scientists from the University of California-Irvine (UCI) and the University of Michigan describe how they found high levels of airborne pollutants, including the carcinogens 1,3-butadiene and benzene, downwind of Canada's industrial heartland in Alberta.
When they examined health records going back 10 years, they found higher levels of leukemia and non-Hodgkins lymphoma in men living near the pollution plumes than in neighboring areas not close to the pollution.
Although they do not claim that the pollutants they documented were the cause of the cancers in the men, they nonetheless call for a reduction in pollution levels as a protective measure for the industrial workers and people living nearby.
Lead author and chemist at UCI, Isobel Simpson, says:
"Our study was designed to test what kinds of concentrations could be encountered on the ground during a random visit downwind of various facilities. We're seeing elevated levels of carcinogens and other gases in the same area where we're seeing excess cancers known to be caused by these chemicals."
"You can study it and study it, but at some point you just have to say, 'Let's reduce it.'"
Her sentiments are echoed by co-author Stuart Batterman, professor of environmental health sciences at the University of Michigan.
"These levels, found over a broad area, are clearly associated with industrial emissions," he says. "They also are evidence of major regulatory gaps in monitoring and controlling such emissions and in public health surveillance."
High levels of volatile compounds
The scientists took 1-minute outdoor air samples at random times in 2008, 2010 and 2012, in Fort Saskatchewan. This rural area is downwind of Alberta's so-called Industrial Heartland, the site of major refineries, chemical plants and tar sands processors belonging to BP, Shell, Dow and others.
All the samples showed similar results, including levels 6,000 higher than normal for some dangerous volatile organic compounds.
To their surprise, they found the Canadian samples had higher levels of some chemicals than some of the world's most heavily polluted cities. When compared with air samples taken in Mexico City in the 1990s and in today's Houston-Galveston area - known to have high pollution - researchers found Alberta's samples contained more contaminants.
Simpson adds that it appears in some cases the companies responsible for the Alberta emissions are not reporting them all. For instance, the high levels of 1,3-butadiene could only have come from one plant, but that company had not reported any such emissions.