Toxic cyanobacteria at Nakuru sewage oxidation ponds – A potential threat to wildlife

摘要: Abstract Phytoplankton composition and biomass, microcystin content were determined on diverse dates between November 2001 June 2006 in the final oxidation pond of Nakuru town sewage treatment plant. The ponds as well rivulet that drains same are important water sources for some wildlife park. phytoplankton studied mostly comprised coccoid green alga species. However, occasionally cyanobacteria or euglenoids dominant. Among cyanobacteria, Microcystis sp. made periodic appearance phytoplankton, was dominant species occasions. Total biomass varied widely from 48 to 135 mg L −1 (wet weight) while ranged undetectable levels 130 mg L . Most due one a few Detectable cyanotoxin concentrations (sum microcystins) up 551.08 μg mg dry weight (DW) 0.28 μg mg DW total recorded samples collected different dates. Microcystin did not appear correspond suggesting toxin production is possibly triggered by environmental changes proportion toxic strains. An occasional presence microcystins suggests species, which regularly use drinking potentially exposed intoxication. A close monitoring necessary accurately quantify potential impact cyanotoxins these