Toxicity and Accumulation of Lead with Respect to Algae and Cyanobacteria: A Review

Lead is a relatively minor element of the earth's crust but widely distributed in low concentrations in uncontaminated sedimentary rocks and soils. The average content of lead on soil is about 10 mg/kg; the background levels of lead in freshwaters and freshwater sediments are estimated to be below 3 μg/l and 40 μg/g, respectively. Lead is commonly found in water plant tissues but its essentiality has never been proved. The present paper is aimed at summarizing literature data concerning occurrence of lead in water environments and its toxicity and bioaccumulation with respect to algae and cyanobacteria. The data concerning mode of toxic action of lead, factors affecting toxicity and accumulation, concentration factors of lead in algae and cyanobacteria and lead content in various algal and cyanobacterian species are given.