Atmospheric trace metals in Lake Ontario Region

Particles in rural and urban air were collected at two ground sites along the Lake Ontario shoreline in Hamilton Eastport (industrial) and Pt. Petre (ambient). Weather protected filter-based high-flow PM10 and PM2.5 samplers were used. Particulate metal size distribution and abundance depends on the source and prevailing weather conditions. Trace metal content per cubic meter of air (PM10, Pt. Petre January 2005 to April 2006) was As~0.5-1.1, Cd~0.3-11.6, Co~0.06-0.5, Cr~1.5-10.3, Cu~50-230, Fe~50-200, Mn~1.7-6.7, Ni~0.5-3.1, Pb~2.2-7.0, Se~0.4-2.8 and Zn~14-75 ng which can generally represent ambient contributions during that time period. Annual average flux calculated (2004 dry/wet, uniform deposition velocity of 0.2 cm s-1 used for dry deposition) was 23/100, 510/2500 and 170/440 ng/m2/day for Cd, Pb & Se. Captured particulate metals from the Eastport industrial site were found to be 50-100 times ambient level. Results of particle size distribution, particulate metal content, meteorological conditions and other parameters can help to identify potential sources as well as provide better estimates of metal loading by dry/wet deposition in the Great Lakes areas of Ontario.