Environmental Geochemistry and Health

, Volume 33, Issue 5, pp 477–493

Assessing Cd, Pb, Zn human bioaccessibility in smelter-contaminated agricultural topsoils (northern France)

  • Aurélie Pelfrêne
  • Christophe Waterlot
  • Muriel Mazzuca
  • Catherine Nisse
  • Géraldine Bidar
  • Francis Douay
Original Paper


The extractability of Cd, Pb, and Zn was investigated in contaminated agricultural topsoils located in an area highly affected by the past atmospheric emissions of two smelters in northern France in order to assess their mobility and human bioaccessibility. The determination of Cd, Pb, and Zn bioaccessibility (Unified Barge Method, in vitro test) was made to evaluate the absolute trace element (TE) bioavailability. The results highlighted differences in bioaccessibility between Cd, Pb, and Zn (Cd > Pb > Zn). The mean values of the bioaccessible fractions of Cd, Pb, and Zn during the gastric phase were 82, 55, and 33%, respectively, of the pseudototal concentrations, whereas during the gastrointestinal phase, the bioaccessible fractions of metals decreased to 45, 20, and 10%, respectively. Stepwise multiple regression analysis showed that human bioaccessibility was affected by various physicochemical parameters (i.e., sand, carbonates, organic matter, assimilated P, free Al oxides, and pseudototal Fe contents). Sequential extractions were performed as an indication of the TE availability in these soils. Cadmium occurred in the more available fractions, Pb was mostly present as bound by oxides, and a significant contribution to the pseudototal Zn concentration was defined as the unavailable residual form related to the crystalline structures of minerals. The concepts of bioavailability and bioaccessibility are important for quantifying the risks associated with exposure to environmental pollutants and providing more realistic information for human health.


Trace elements Contaminated soil Bioaccessibility In vitro digestion Sequential extractions 


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© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Aurélie Pelfrêne
    • 1
    • 2
  • Christophe Waterlot
    • 1
    • 2
  • Muriel Mazzuca
    • 1
    • 3
  • Catherine Nisse
    • 1
    • 3
    • 4
  • Géraldine Bidar
    • 1
    • 2
  • Francis Douay
    • 1
    • 2
  1. 1.Univ Lille Nord de FranceLilleFrance
  2. 2.Groupe ISA, Equipe Sols et Environnement, Laboratoire Génie Civil et géoEnvironnement Lille Nord de France, EA 4515Lille CedexFrance
  3. 3.UDSL, EA 4483, Impact de l’Environnement Chimique sur la Santé HumaineLilleFrance
  4. 4.CHULille, Service de Pathologie Professionnelle et EnvironnementLilleFrance

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