DEQ led a groundbreaking study to estimate levels of toxic air pollutants and their associated risk in the Portland area; and draw together local governments, affected communities and businesses through an advisory committee to provide recommendations to reduce health risk. The Portland Air Toxics Solutions study ran from 2009-2012. It estimated ambient concentrations of 19 air toxic air pollutants and their associated risk in the Portland Metropolitan area for the year 2017.
Emissions from urban sources (i.e., manufacturers, paint and solvent facilities, gas stations, and residential wood burning) based on the 2005 emissions inventory were projected to the year 2017, taking into account changing economic conditions and population growth. DEQ inputted the projected 2017 emissions, population, and weather into the dispersion model Calpuff to estimate the ambient concentrations of these 19 air toxics, their associated risk, and the sources driving the risk.
The PATS model indicated that gasoline & diesel engines and residential wood burning would be the main source of air toxics health risk across the Portland Metropolitan in 2017. Areas close to industrial facilities using heavy metals also showed heightened health risk. The environmental justice analysis further demonstrated that disproportionate impacts from toxic air pollutants occurred for minority and low-income populations in the Portland Metropolitan area.