Rural particulate matter in Alberta, Canada

Characteristics of particulate matter in rural Alberta locations were examined and compared with those in cities. Mean PM2.5 and PM10 concentrations at remote rural Albzrtalocations are 3.2 and 8.8 mu g m(-3), respectively. However, PM2.5 and PM10, concentrations at rural locations within 100km of regional industrial and urban sources are 7.9 and 16.8 mu gm(-3), respectively. The mean PM2.5 to PM10 ratio in remote rural Alberta is about 0.4, similar to that observed in the cities. However, the ratio is about 0.5 in the rural locations influenced by regional sources. The PM2.5 values at remote rural locations are about one-third of those observed in urban centres in Alberta. PM2.5, concentrations in remote rural areas seem to constitute a "regional background" for Alberta. Sulphate content in PM2.5, at remote rural locations varies from 0.3 to 1.4 mu gm(-3). A mean PM2.5 sulphate content of 22% in rural Alberta is in the same range as that observed at nonurban sites in the northwestern United States. (C) 2000 Elsevier Science Ltd. All rights reserved.