I am not an expert on pollution at airports but have spent considerable time on gaseous pollutants in hospitals
The minimum safe levels are not based on evidence of risk. Most started by being plucked from the air, but politicians who are not responsible for the cost of compliance have reduced maximum permitted levels with little scientific basis
Proving or demonstrating cause and effect between pollutants and cancer is even more problematical. Cancer clusters are common and statistically do not demonstrate causation. We spent seven years looking at the relation between anaesthetic waste gases and abortion in nurses and despite the thousands of anaesthetics, hundreds of hospitals and many nurses proved nothing.
So I very much doubt you will demonstrate several people got cancer in one location due to an environmental pollutant. There may be claims to this effect, but as to proof.......
That is not to say that these contaminants may not put people at risk of various medical illnesses.
Interested in any other views