BLOOD LEAD LEVELS IN NORANDA CHILDREN FOLLOWING REMOVAL OF SMELTER-CONTAMINATED YARD SOIL

In 1979, children two to five years of age living in Rouyn-Noranda, QC , in an urban district located within 1 km from a copper smelter had m ean (geometric) blood lead levels (BLL) of 21 mug/dL. Afterwards, stac k emissions were lowered. In 1989 mean (geom.) BLL were reduced to 11 mug/dL; 50% of the district children had BLL less than 10 mug/dL. In 1 990-91, a $3 million top soil removal operation took place; residentia l lots having more than 500 ppm soil lead were decontaminated. In 1991 , BLL were reduced to 7 mug/dL; 75% of the children had less than 10 m ug/dL. Geographic analysis of the 1991 results showed that children wi th the highest BLL lived nearest to the smelter, where atmospheric dus tfall to the ground reached 36 mg/m2/month. Follow-up pediatric blood lead campaigns are planned in 1993 and 1995, to evaluate the effects o f an ongoing program for further reduction of atmospheric smelter emis sions.