title: Manganese and lead in children's blood and airborne particulate matter in Durban, South Africa.
abstract: Despite the toxicity and widespread use of manganese (Mn) and lead (Pb) as additives to motor fuels and for other purposes, information regarding human exposure in Africa is very limited. This study investigates the environmental exposures of Mn and Pb in Durban, South Africa, a region that has utilized both metals in gasoline. Airborne metals were sampled as PM(2.5) and PM(10) at three sites, and blood samples were obtained from a population-based sample of 408 school children attending seven schools. In PM(2.5), Mn and Pb concentrations averaged 17±27 ng m(-3) and 77±91 ng m(-3), respectively; Mn concentrations in PM(10) were higher (49±44 ng m(-3)). In blood, Mn concentrations averaged 10.1±3.4 μg L(-1) and 8% of children exceeded 15 μg L(-1), the normal range. Mn concentrations fit a lognormal distribution. Heavier and Indian children had elevated levels. Pb in blood averaged 5.3±2.1 μg dL(-1), and 3.4% of children exceeded 10 μg dL(-1), the guideline level. Pb levels were best fit by a mixed (extreme value) distribution, and boys and children living in industrialized areas of Durban had elevated levels. Although airborne Mn and Pb concentrations were correlated, blood levels were not. A trend analysis shows dramatic decreases of Pb levels in air and children's blood in South Africa, although a sizable fraction of children still exceeds guideline levels. The study's findings suggest that while vehicle exhaust may contribute to exposures of both metals, other sources currently dominate Pb exposures.
authors.affiliation: Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI, USA. stuartb@umich.edu
authors.forename: Stuart
authors.initials: S
authors.lastname: Batterman
authors.forename: Feng-Chiao
authors.initials: FC
authors.lastname: Su
authors.forename: Chunrong
authors.initials: C
authors.lastname: Jia
authors.forename: Rajen N
authors.initials: RN
authors.lastname: Naidoo
authors.forename: Thomas
authors.initials: T
authors.lastname: Robins
authors.forename: Inakshi
authors.initials: I
authors.lastname: Naik
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000097:blood*; D002648:Child; D004781:Environmental Exposure / Q000032:analysis / Q000706:statistics & numerical data; D004784:Environmental Monitoring; D005260:Female; D006801:Humans; D007854:Lead / Q000032:analysis / Q000097:blood*; D008297:Male; D008345:Manganese / Q000032:analysis / Q000097:blood*; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis / Q000378:metabolism*; D013019:South Africa; D001335:Vehicle Emissions / Q000032:analysis
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D001335:Vehicle Emissions; D007854:Lead; D008345:Manganese