Measuring environmental quality: an index of pollution

This paper develops an index of pollution based on the epidemiological dose -response function associated with each pollutant, and the welfare losses d ue to exposure to pollution. The probability of damage is translated into w elfare losses, which provides the common metric required for aggregation. I sopollution surfaces may then be used to compare environmental quality over time and space. An Air Pollution Index (API) is computed using 1997 data f or the criteria pollutants under the Clean Air Act (CAA). The results are c ompared with the EPA's Pollutant Standards Index (PSI). Two significant dif ferences emerge: unlike the PSI, the API facilitates a detailed ranking of regions by air quality and API values may contradict PSI results. Some regi ons with PSI values of 100-200 are considered less polluted under the propo sed methodology than those with PSI values between 50 and 100. The key reas on for the difference is that PSI values are determined entirely by the gas with the highest relative concentration whereas the API value is based on the ambient concentrations of all pollutants. (C) 2000 Elsevier Science B.V . All rights reserved.