Microbial diversity in heavy-metal polluted waters

Abstract

Indigenious water microflora as well as the presence of metal- and xenobiotic biotransforming bacteria were investigated in waters near the KCM Pb-Zn smelter, South Bulgaria. Content of As, Hg, Cd, Mn, Pb, Cu and Zn exceeded in times the maximum permission standart. Absence of some microbial groups demonstrated a change in the microbial community structure in the region. Ecotoxicology test ISO/DIS 10712.2 displayed toxic environmental effect of the polluted waters, especially one of them which demonstrated 72% ofn ecotoxicity. More than 20 ecologically relevant new bacteria were cultured. Three of them demonstrated tolerance to Cd, Cu and Mn and five- a tolerance to 2,4-dichlorphenoxyacetic acid. Our result revealed that the heavy metal pollutions reduced the microbial diversity in the studied waters, are ecotoxic as well as that some of newly isolated bacteria possess a capacity for a clean-up biotechnologies in the region. © 2005 Taylor and Francis Group, LLC.