Water quality bio-assay is a modern, important and relevant study to determine the safety of water resources in Ukraine. In accordance with the guidelines for the development of standards for maximum discharge of pollutants into water bodies with return waters, approved by the order of the Ministry of Environment for № 173 from 05.03.2021, Resolution of the Cabinet of Ministers of Ukraine №758 from 19.09.2018 “On approval of the Procedure for state water monitoring ”, the level of toxicity should be determined on the basis of bioassay in return waters.
Bioassay is an experimental determination, experimental evaluation of the influence of factors (physical, chemical, physicochemical) or a group of harmful factors on living organisms by recording changes in a biological indicator (physiological, biochemical, cytogenetic, etc.) observed in the experimental test. object (indicator) in comparison with the control in clearly defined (ie, standard laboratory conditions).
Aquatic bio-assay is based on determining changes in the survival and fertility of crustaceans due to the action of toxic substances contained in the test water, compared with these indicators in the control conditions.
The methodology and results of bio-assay are normatively approved both in Ukraine and in the world.
Bio-assay also detects the body’s response to a certain type of contamination. It helps to adjust the MPC calculations of pollutants in wastewater when their dilution in the water body does not provide an acceptable level.
Center Ltd. Ltd. conducts bioassay (acute and chronic research) for toxicity of natural, technical, sewage, sewage, drinking water, water extracts, fish feed, medicines, fertilizers, agricultural products and other substances that may get into the aquatic environment, using as test objects Daphnia magna Straus (Cladocera, Crustacea) in accordance with the requirements of state regulations (DSTU 4173-2003 “Water quality. Determination of acute lethal toxicity to Daphnia magna Straus and Ceriodaphnia affinis Lilljeborg (Cladocera , Crustacea) (ISO 6341: 1996, MOD) and DSTU 4174-2003 “Water quality. Determination of chronic toxicity of chemicals and water to Daphnia magna Straus and Ceriodaphnia affinis Lilljeborg (Cladocera, Crustacea) (ISO 10706: 2000, MOD).
The results of acute research, in accordance with the legislative regulations of Ukraine are the determination of the following standardized parameters on test objects Daphnia magna Straus (Cladocera, Crustacea):
- mortality rate of bioassay;
- lethal concentration (LC)
- average lethal concentration (LC50)
- other additional parameters depending on a subject and the purpose of researches.
Water quality bio-assay can prevent possible effects of toxins on human health and the environment, timely develop measures to reduce and prevent exposure to protect the business entity from possible adverse actions of regulatory authorities, penalties, negative public opinion in the implementation of the planned activities.