A study released Thursday by local researchers finds people living in Allegheny County have a substantially higher risk of getting cancer due to simply breathing the air over the course of their life time than those who live in 20 other counties in the area.
The report from the Heinz Endowments-supported Breath Project based its findings on publicly available data looking at the predicted levels of more than 200 toxic air pollutants.
“Some of them are very, very low concentrations, therefore it's not really feasible or does not really make that much sense to monitor all of these,” said Drew Michanowicz, lead study author. “Therefore, all of these estimates are based on emissions models.”
The federal government looks at all of the pollution permits in an area, applies climate, geography and other models and then comes up with an estimate of how much of each pollutant should be in any zip code or census tract. Those numbers are then pushed through laboratory setting-based models to determine the level of risk associated with breathing the air for 70 years.
Michanowicz said recent studies out of Carnegie Mellon University validated the models by taking actual air samples from downtown Pittsburgh, Oakland and South Fayette Township and comparing them to the expected levels.
Those studies found the federal government in general was close but its models slightly underestimated the impacts of large stationary sources, such as a coke plant, and slightly overestimated the impact of small moveable sources such as trucks.
The study looked at the data if diesel pollution was removed from the equation because such pollution is higher in all metropolitan areas compared to rural areas. Those numbers show Allegheny County still has 5 of the top 7 census tracks when it comes to cancer risk.
“Now we have to try and get the public to understand this in a reasonable way, to have a reasonable conversation with people that are involved in a policy and regulatory kind of thing,” Michanowicz said.
The report also found the highest risks are for those living in the southeastern corner of Allegheny County, the neighborhoods downwind from Neville Island and those downwind from downtown Pittsburgh.