Environmental Monitoring and Assessment

, Volume 184, Issue 5, pp 3027–3042 | Cite as

Metal speciation studies in the aquifer sediments of Semria Ojhapatti, Bhojpur District, Bihar

  • Alok Kumar
  • A. L. Ramanathan
  • Shashi Prabha
  • Rajesh Kumar Ranjan
  • Shyam Ranjan
  • Gurmeet Singh


The pollution of aquifer sediments by heavy metals has assumed serious concern due to their toxicity and accumulative behavior. Changes in environmental conditions can strongly influence the behavior of both essential and toxic elements by altering the forms in which they occur and therefore quantification of the different forms of metal is more meaningful than total metal concentrations. In this study, fractionation of metal ions in aquifer sediments of Semria Ojhapatti area, Bhojpur district, Bihar has been studied to determine the ecotoxic potential of metal ions. The investigations suggest that iron, copper, and arsenic have a tendency to remain associated in the following order residual > reducible > acid-soluble > oxidizable; manganese and zinc have tendency to be associated as residual > acid-soluble > reducible > oxidizable. The risk assessment code reveals that manganese and zinc occur in significant concentration in acid-soluble fraction and therefore comes under the high risk category and can easily enter the food chain. Most of the iron, copper, and arsenic occur as immobile fraction (i.e. residual) followed by its presence in reducible fraction and would pose threat to the water quality due to changing redox conditions. The metal enrichment factor in the study area shows moderate to significant metal enrichment in the aquifer sediments which may pose a real threat in near future. The geo-accumulation index of metals also shows that the metals lie in the range of strongly contaminated (for iron at shallow depths) to moderately contaminated to uncontaminated values.


Aquifer Sediments Metal fractionation Risk assessment code Enrichment factor 



The authors acknowledge Jawaharlal Nehru University, New Delhi for the necessary infrastructure to carry out the research work, the Council of Scientific and Industrial Research, Government of India for providing financial assistance in the form of CSIR-JRF scholarship, and the Swedish International Development Cooperation Agency (SIDA) for the field work assistance.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Alok Kumar
    • 1
  • A. L. Ramanathan
    • 1
  • Shashi Prabha
    • 1
  • Rajesh Kumar Ranjan
    • 1
    • 2
  • Shyam Ranjan
    • 1
    • 3
  • Gurmeet Singh
    • 1
    • 4
  1. 1.Biogeochemistry, Hydrogeochemistry and Glaciology Laboratory, School of Environmental SciencesJawaharlal Nehru UniversityNew DelhiIndia
  2. 2.School of Earth, Biological and Environmental SciencesCentral University of BiharPatnaIndia
  3. 3.Climate and Environmental Physics, Physics InstituteUniversity of BernBernSwitzerland
  4. 4.Environmental Science DivisionIndian Agricultural Research Institute, PUSANew DelhiIndia

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