2nd International UNIDOKAP Black Sea Symposium, Samsun, Turkey, 28 - 30 November 2018, vol.1, pp.28-32
The only chemical analysis of pollutants in ecosystems is not correct in proving the toxicological effects
of biota. Besides the chemical structure of the pollutants; ecological and toxicological effects and an
integrated study are required. Only through an integrated study can the ecotoxicological effects of
contaminating ecosystems such as sediments be accurately determined. For this reason, biological and
toxicological methods should be applied along with chemical methods for ecotoxicological studies.
Contamination in the aquatic environment disturbs the self-cleaning capacity of aquatic ecosystems,
reaching dangerous dimensions. Therefore, aquatic organisms are used for the determination of the
danger coming from the water. Organisms can be considered as a means of integrating sampling because
they live in balance with the environment surrounding them. Organisms can provide an understanding
of the nature of the relationship between contaminants in the organism and the resulting biological
effects of pollutants. In this study, a toxicity test was conducted with Daphnia magna (Straus, 1820;
Cladocera, Daphniidae), a bioindicator species commonly used in ecotoxicology.
Four different concentrations of samples were prepared from sediments of Seydişehir as 0.025 mg ml-1,
0.05 mg ml-1, 0.1 mg ml-1 and 0.2 mg ml-1, and 5 pcs of D. magna neonate were added to them. Observed
for 48 hours after the required ambient conditions were met.
D. magna were monitored at 12, 24, and 48-hour intervals, and the number of organisms living and
dying after 48 hours was determined. It was observed that the vital activities of the organisms continued
at the 12 and 24-hour controls after the test started. Acute toxicity of D. magna was determined at
Seyhişehir sediment sample after 48 hours and LC50 (lethal concentration) was found to be 0,101 mg
ml-1.
Keywords: Daphnia magna, ecotoxicology, sediment.