Speciation in Metal Toxicity and Metal-Based Therapeutics

Speciation in Metal Toxicity and Metal-Based Therapeutics

Metallic elements, ions and compounds produce varying degrees of toxicity in organisms with which they come into contact. Metal speciation is critical to understanding these adverse effects; the adjectives "heavy" and "toxic" are not helpful in describing the biological properties of individual elements, but detailed chemical structures are. As a broad generalization, the metallic form of an el...

Metal-Based Therapeutics for Leishmaniasis

Speciation Studies and Toxicity Assessment of Complex Heavy Metal Mixtures

The MicrotoxTM bioassay and polarographic techniques were used together to identify specific oxidation states and toxicity of metals. The bioassay is based on light reduction by bioluminescent bacteria upon exposure to toxicants. In polarography, a mercury drop substrate’s potential is changed, and the substance of interest is electrochemically reduced. Reduction current is proportional to its ...

Metal and proton toxicity to lake zooplankton: a chemical speciation based modelling approach.

The WHAM-FTOX model quantifies the combined toxic effects of protons and metal cations towards aquatic organisms through the toxicity function (FTOX), a linear combination of the products of organism-bound cation and a toxic potency coefficient for each cation. We describe the application of the model to predict an observable ecological field variable, species richness of pelagic lake crustacea...

Metal speciation in environmental and biological systems.

Metal ions form complexes with naturally occurring complexing agents or ligands released from industrial activity. The metal complexes are thereby mobilized and transported in environmental and biological systems. The impact of such metal complexes depends on the metal complex species that are kinetically and thermodynamically stable in these homogeneous and heterogeneous systems. The distribut...