Using soil properties to predict in vivo bioavailability of lead in soils

M. A.Ayanka Wijayawardena, Ravi Naidu, Mallavarapu Megharaj, Dane Lamb, Palanisami Thavamani, Tim Kuchel

Research output: Contribution to journalArticlepeer-review

25 Citations (Scopus)


Soil plays a significant role in controlling the potential bioavailability of contaminants in the environment. In this study, eleven soils were used to investigate the relationship between soil properties and relative bioavailability (RB) of lead (Pb). To minimise the effect of source of Pb on in vivo bioavailability, uncontaminated study soils were spiked with 1500mg Pb/kg soil and aged for 10-12months prior to investigating the relationships between soil properties and in vivo RB of Pb using swine model. The biological responses to oral administration of Pb in aqueous phase or as spiked soils were compared by applying a two-compartment pharmacokinetic model to blood Pb concentration. The study revealed that RB of Pb from aged soils ranged from 30±9% to 83±7%. The very different RB of Pb in these soils was attributed to variations in the soils' physico-chemical properties. This was established using sorption studies showing: firstly, Freundlich partition coefficients that ranged from 21 to 234; and secondly, a strongly significant (R2=0.94, P<0.001) exponential relationship between RB and Freundlich partition coefficient (Kd). This simple exponential model can be used to predict relative bioavailability of Pb in contaminated soils. To the best of our knowledge, this is the first such model derived using sorption partition coefficient to predict the relative bioavailability of Pb.

Original languageEnglish
Pages (from-to)422-428
Number of pages7
Publication statusPublished or Issued - 1 Nov 2015


  • In vivo
  • Relative bioavailability
  • Soil properties
  • Sorption
  • Swine

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Chemistry(all)
  • Pollution
  • Public Health, Environmental and Occupational Health
  • Health, Toxicology and Mutagenesis

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