Journal of Korean Society on Water Environment (한국물환경학회지)

Korean Society on Water Environment (한국물환경학회)
권호 표지

The Theory and Application of Diffusive Gradient in Thin Film Probe for the Evaluation of Concentration and Bioavailability of Inorganic Contaminants in Aquatic Environments

박막분산탐침(diffusive gradient in thin film probe)의 수중 생물학적 이용가능한 중금속 측정 적용

  • Hong, Yongseok (Daegu University, College of Engineering, Department of Environmental Engineering)
  • 홍용석 (대구대학교 공과대학 환경공학과)
  • Published : 2013.09.30
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Abstract

This review paper summarizes the theory, application, and potential drawbacks of diffusive gradient in thin film (DGT) probe which is a widely used in-situ passive sampling technique for monitoring inorganic contaminants in aquatic environments. The DGT probe employs a series of layers including a filter membrane, a diffusive hydrogel, and an ionic exchange resin gel in a plastic unit. The filter side is exposed to an aquatic environment after which dissolved inorganic contaminants, such as heavy metals and nuclides, diffuse through the hydrogel and are accumulated in the resin gel. After retrieval, the contaminants in the resin gel are extracted by strong acid or base and the concentrations are determined by analytical instruments. Then aqueous concentrations of the inorganic contaminants can be estimated from a mathematical equation. The DGT has also been used to monitor nutrients, such as ${PO_4}^{3-}$, in lakes, streams, and estuaries, which might be helpful in assessing eutrophic potential in aquatic environments. DGT is a robust in-situ passive sampling techniques for investigating bioavailability, toxicity, and speciation of inorganic contaminants in aquatic environments, and can be an effective monitoring tool for risk assessment.

Keywords

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