Review of toxicity of cyanobacteria in Slovakia

Although the dominance of cyanobacterial species forming water blooms in Sl ovakia has been well documented for many years, the toxicity of their popul ations has not been monitored. The results of analysis of hepatotoxic micro cystins identified and quantified by HPLC with diode array detector are rep orted, as well as a rapid clean-up method based on centrifugal ultrafiltrat ion of crude cyanobacterial extract, which can replace conventional time co nsuming solid-phase extractions. The toxicity of cyanobacterial biomass was confirmed by bioassay using the crustacean species Thamnocephalus platyuru s. Level of microcystin-LR, ranged from 0 up to 1445.5 mug/g d.w. Variabili ty in microcystin contents within different localities was noticed. Not onl y common bloom-forming species (Microcystis flos-aquae, M. aeruginosa, Plan ktothrix agardhii or Anabacna circinalis), but also Cylindrospermopsis raci borskii and Raphidiopsis mediterranca were identified to be dominant specie s in some cyanobacterial blooms in W Slovakia. Blooms dominated by cyanobac teria were observed in lakes, fishponds, and water reservoirs. Increased at tention should be paid to the effects of cyanobacterial toxins on human hea lth and health of aquatic ecosystems in general.