“The lack of quality exposure data is the “Achilles’ heel” of research on the health impacts of air pollution, King’s College London Professor Frank Kelly said last week.”
“The lack of quality exposure data is the “Achilles’ heel” of research on the health impacts of air pollution, King’s College London Professor Frank Kelly said last week.”
The love canal incident had exposure measurement problems too. When the State of New York State did a predicted versus observed analysis of those living at Love Canal using careful calculations of exposures, all the observed numbers of the various cancers studied fell within the one stand deviation error bars of the background rates. According to the New York Study, nobody was hurt by Love Canal.
All EPA exposure risks use computed ground level concentrations. The concentrations are computed by use of dispersion models coupled with estimated emissions from air pollution sources. The models are conservative, by approximately a factor of 4. The models calculations are rarely compared to ground level measurements, even in the areas that actual monitoring occurs. The monitors are used solely for comparison of existing levels to air quality regulations.
Exposures are estimated by calculating estimated ground level concentrations to census tract estimates of the population density in areas. No one verifies the accuracy of either estimate. No one factors in the duration of actual exposure. The entire process is a computation.