Veronika Pašková


Toxicity and sub-lethal effects of cyanobacteria on model aquatic organisms


Masaryk University, Faculty of Science,

Research Centre for Toxic Compounds in the Environment (RECETOX)

Brno, Czech Republic, 2010



Cyanobacterial water blooms represent a problem throughout the world due to the eutrophication of
the aquatic environment in particular. The production of wide range of secondary metabolites
including cyanotoxins belongs to consequential problems connected with the occurrence of
cyanobacterial blooms in the surface water. A wide range of aquatic organisms including
invertebrates, fish and amphibian, mammalian or avian species may be exposed to cyanobacterial
metabolites and other compounds via consumption of or dermal contact with water contaminated by
cyanobacteria.

During the last decades, mortalities of wild birds have been associated with the toxic
cyanobacterial blooms worldwide; however these data were mostly based on indirect evidence. The
intention of our research group was to complement field observations published by other workers
with results from laboratory experiments on the model bird Japanese quail (Coturnix coturnix
japonica). We have performed evidence-based avian toxicity test with different doses of
cyanobacterial biomass with controlled levels of cyanotoxins microcystins (MCs) to evaluate the
effective concentration of MCs. In consequent experiments we have set up more relevant
environmental scheme with multiple exposures to cyanobacterial biomass, heavy metal lead and
vaccination to simulate the natural conditions. In both the experiments the sub-lethal parameters
of oxidative stress (lipid peroxidation), detoxification and antioxidative markers (glutathione,
glutathione-S-transferase, glutathione reductase, glutathione peroxidase, catalase, superoxide
dismutase) were measured together with accumulation of MCs, Pb in their tissues. These parameters
were reviewed together with haematological and histopathological parameters examined by our
colleagues from University of Veterinary and Pharmacy and the complex effects of cyanobacterial
biomass on the model birds were summarized.

The aim of the presentation will be the summary of the recently performed experiments and results
and the overview of the future experiments.