Archives of Environmental Contamination and Toxicology

, 57:477

Effect of pH, EDTA, and Anions on Heavy Metal Toxicity Toward a Bioluminescent Cyanobacterial Bioreporter

  • Ismael Rodea-Palomares
  • Coral González-García
  • Francisco Leganés
  • Francisca Fernández-Piñas
Article

DOI: 10.1007/s00244-008-9280-9

Cite this article as:
Rodea-Palomares, I., González-García, C., Leganés, F. et al. Arch Environ Contam Toxicol (2009) 57: 477. doi:10.1007/s00244-008-9280-9

Abstract

The bioavailability and therefore toxicity of a metal depends on the chemical species present in a particular environment. We evaluated the effect of a series of factors that could potentially modify metal speciation on the toxicity of Hg, Cu, Zn, and Cd toward a recombinant strain of the freshwater cyanobacterium Anabaena sp. PCC 7120 with cloned lux operon of luminescent terrestrial bacterium Photorhabdus luminescens. The strain, denoted as Anabaena CPB4337, showed a high constitutive luminescence with no need to add exogenous aldehyde. The tested factors were pH, EDTA (as organic ligand), and anions PO43–, CO32–, and Cl. Chemical modeling and correlation analyses were used to predict metal speciation and link it with toxicity. In general, metal toxicity significantly correlated to the predicted metal free-ion concentration, although Zn–EDTA complexes and certain Hg chloro-complexes could also exhibit some toxicity to cyanobacteria. An interesting feature of metal toxicity to strain Anabaena CPB4337 was that low amounts of PO43– and CO32– increased metal toxicity; this effect could not be related to significant changes in metal speciation and could be attributed to a modulating effect of these anions on metal/uptake toxicity. The combination of toxicity studies that take into account a range of factors that might modulate metal toxicity with chemical modeling to predict changes in metal speciation might be useful for interpreting complex toxicity data. Finally, this cyanobacterial bioreporter, due to its ecological relevance as a primary producer, could be used as a tool for toxicity assessment in freshwater environments.

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Ismael Rodea-Palomares
    • 1
  • Coral González-García
    • 1
    • 2
  • Francisco Leganés
    • 1
  • Francisca Fernández-Piñas
    • 1
  1. 1.Departamento de Biología, Facultad de CienciasUniversidad Autónoma de MadridMadridSpain
  2. 2.Instituto de Salud Carlos IIICentro Nacional de MicrobiologíaMadridSpain