Northern Curonian Lagoon in the Southeast Baltic Sea, data set limits: 55 16 - 55 44N; 21 01 - 21 17E (55 55 21 21) Lithuanian territorial waters and economic zone, data set limits: 55 19 - 56 02N; 19 14 - 21 05E (pataisyti)

Bioassay and contaminant biological impact

Spectrophotometers

The aim of the experiment was to determine the influence of petroleum hydrocarbons and the dispersing agent 'Simple green' on organisms in fresh and sea water using TOXKIT microbiotests and to define which toxic substance - the petroleum hydrocarbons or the dispersing agents are more harmful for water biota. In order to achieve the results bioresearches with microbiotests (Daphtoxkit FTM (Daphnia magna), Thamnotoxkit FTM (Thamnocephalus platyurus), Artoxkit MTM (Artemia salina), which analyse the influence of the dispersing agents and the petroleum hydrocarbons on organisms, were performed, the sensibility of the test - organisms was analysed and determined, and the toxicity of the investigated substances was evaluated. After the bioresearches with the mentioned microbiotests was performed, the toxicity of the investigated substances for test organisms was determined: LC50 (LC50 - lethal concentration) of the emulsion on the test organism D. magma 48 h LC50 =0.3 mg/l; the LC50 of the dispersing agent 'Simple Green' on: D. magna - 24 h LC50=109.4 mg/l and 48 h LC50=75.7 mg/l; on Th.platyurus - 24 h LC50=108.3 mg/l, A. salina - 24 h LC50=843.4 mg/l and 48 h LC50=702.4 mg/l; LC50 of the dispersing agent 'Simple Green' in the mixture of the emulsion: D. magna - 48 h LC50=164 mg/l 'Simple Green', Th.platyurus - 24 h LC50=183 mg/l 'Simple Green', A. salina - 24 h LC50=698 mg/l 'Simple Green' and 48 h LC50=440 mg/l 'Simple Green'. The LC50 of petroleum hydrocarbons and the dispergent agent 'Simple Green' on water organisms is different though there is no doubt about their toxicity. After the evaluation of the effects produced by the dispersing agent, the emulsion and the mixture of the emulsion and the dispersing agent 'Simple green' those substances according to the toxicity can be lined up this way: Emulsion > the mixture of the emulsion and the dispersing agent 'Simple Green' > the dispersing agent. In conclusion, it is possible to state that the oil and its products are more toxic than modern dispersing agents. However, it is necessary to perform repeated analyses in order to receive more precise information.

Riepsaite M. (2002) The evaluation of the toxicity of the petroleum hydrocarbons and dispersant 'Simple Green' using Toxkit microbiotests. // Proceeding. Center of Marine Research. 51 p. (in Lithuanian), ; Riepsaite M. (2003) Toxicity of the petroleum hydrocarbons and some oil dispersants. // Graduation dissertation. The Klaipeda University, Lithuania, 65 p. (in Lithuanian),

Department of Marine Research of the Environmental Protection Agency
Taikos Av. 26
Klaipeda

LT-91149
Lithuania