Proposed Reductions in Ozone NAAQS - Good Science or Perpetuation of Dogma on Health Consequences of Low-Level Air Pollution?

摘要

While much debate continues regarding the level at which adverse health effects occur and the relationship between monitored O_3 concentrations and mortality/hospitalization reported in epidemiology studies, EPA has presumed that adverse effects occur at O_3 concentrations as low as 60 ppb and that O_3 causes the reported deaths/hospitalization for the sake of estimating risks and risk reductions associated with meeting alternative standards in the recently released Risk and Exposure Assessment (REA)11. However, the total risk and the reductions in risk associated with meeting the alternative standards between 60 and 70 ppb estimated in the REA are relatively small. This indicates that the existing O_3 NAAQS of 75 ppb is protective of public health and little if any benefit is to be gained by lowering the standard, particularly in light of the weak evidence for the health thresholds evaluated.