SOIL LEAD LEVELS IN A SMALL TOWN ENVIRONMENT - A CASE-STUDY FROM MT-PLEASANT, MICHIGAN

Few studies are made on the potential soil Pb burden for a small city in a rural environment. Data obtained by atomic absorption spectrophotometry suggest a somewhat weak significant positive relationship (r = 0.27) between increased traffic volume and roadside soil Pb content. Median soil Pb levels along the most heavily travelled roads are 320-mu-g g-1 while background concentrations are 200-mu-g g-1. No significant relationship is found between predominant wind direction and soil Pb content. Zones where cars idle have only slightly elevated Pb levels. Older homes have soil Pb values exceeding 1000-mu-g g-1; a significant positive relationship (r = 0.59) exists between increasing soil Pb and home age. Schools, which are mainly located away from heavily travelled roads and typically of brick construction, have soil Pb concentrations at background levels. In general, the small city Pb burden is lower than in major urban areas. However, soils around older homes and in special locales, such as salvage yards, have Pb levels comparable to major urban areas.