Trends of Airborne Particulate Lead in Ontario: 1971–1979

Review and recommendations on a lead in soil guideline

“…The MOE Air Quality Criterion for a 24-hour sample is 5.0 ug/m^, while the Air Quality Criterion for a^O -^ay geometric mean concentration is 2 ug/m^ (Heidorn and Rohac, 1984).…”

“…In order to determine ambient airborne lead concentrations in Ontario, the Province of Ontario established air lead monitoring in 1969, and has subsequently expanded these efforts to establish an Ontario Lead Monitoring Network. Data collected between 1972 and 1982 indicate that airborne lead concentrations in Ontario decreased by 79% over this period, primarily as a result of decreased lead emissions from automobiles (Heidorn and Rohac, 1984). A summary of air lead data collected between 1983 and 1986 in Ontario indicates that rural areas of Ontario had annual geometric mean air lead concentrations ranging from 0.1 to 0.2 ug/m^, that urban areas of Ontario unaffected by point-source lead emissions had annual geometric mean air lead levels ranging from 0.1 to 0.3 ug/m^, and that annual geometric mean air lead levels in the vicinity of industrial point sources of lead ranged from 0.2 to 2.1 ug/m^ (Kurtz, 1987).…”