Project Details:

Humic-metal binding constants database

Systematic compilation of data on complexation of trace metals by humic substances and construction of a database to facilitate its access

BACKGROUND - The significance of natural organic matter (NOM) in determining trace metal speciation in aquatic systems has long been recognised. The polyfunctional and polyelectrolytic nature of these ligands provides an effective buffer for metal ion concentrations and as such is essential for the maintenance of life. However, despite an enormous number of studies, many unresolved aspects remain, e.g. the relative contribution of different types of NOM (e.g. humic-type substances versus biota exudates) to overall metal binding, or the relative degree to which different trace metals are bound by a given NOM type. Furthermore, no systematic compilation of published data exists, thus making any quantitative appraisal difficult.

AIM - We have undertaken the compilation of data published over the past 40 years. It includes collection of data on trace metal binding by different types of NOM. Our long-term aim is the critical analysis and interpretation of all data published for complexation of trace metals by NOM in natural water systems with the objective of providing a robust framework for further research.
The first step is the development of a comprehensive database of published values for humic substances. Since we believe that such a compilation may be useful to any scientist working in the field, independently of the objective of his/her work, the data compiled will be stored in a web-based database.

> project announcement published in Chem. Int. May-June 2009

last update 20090522

• Filella, Montserrat

• Hummel, Wolfgang
• May, Peter
• Puy, Jaume
• Quentel, François