CYST-BASED ECOTOXICOLOGICAL TESTS USING ANOSTRACANS - COMPARISON OF 2SPECIES OF STREPTOCEPHALUS

Cyst-based ecotoxicological tests are simple and low-cost methods for assessing acute toxicity. Nevertheless, only a few comparative studies on their sensitivity are known. In the present study, the suitability of the use of two freshwater Anostracan species, Streptocephalus rubr icaudatus and S. texanus, was assessed. The impact of 16 priority poll utants (4 heavy metals, 11 organic, and 1 organometallic compounds) on these two species, as well as on Artemia salina (Artoxkit M), Daphnia magna (International Organization for Standardization 6341), and S. p roboscideus (Streptoxkit F) was assessed. For indicative comparison, b ioassays using Brachionus calyciflorus (Rotoxkit F) and Photobacterium phosphoreum (Microtox) were also performed. For heavy metals (K2Cr2O7 , Cd2+, Zn2+, Cu2+), the sensitivity of the two studied Streptocephalu s species was slightly higher than that of D. magna. It was significan tly more elevated than for the marine A. salina. For organic and organ ometallic micropollutants [phenol, 3,5-dichlorophenol, pentachlorophen ol (PCP), hydroquinone, linear alkylbenzene sulfonate, sodium dodecyl sulfate, tributylphosphate, dimethylphthalate, atrazine, lindane, mala thion, tributyltin chloride (TBT-Cl)], the sensitivity of the 4 anostr acan species was of the same order of magnitude as that of D. magna. A rtemia salina was slightly less sensitive to some organic compounds (P CP, hydroquinone, TBT-Cl). The sensitivity of S. rubricaudatus to orga nic solvents was low. On the other hand, this anostracan was quite sen sitive to NaCl. Thus, its use is restricted to freshwater samples. The evaluation of global practicability of these two tests confirms that cyst-based freshwater anostracans may be used to perform low-cost test s at a sensitivity comparable to that of D. magna (24 h immobilization test). (C) 1994 by John Wiley & Sons, Inc.