| 摘要 |
A method for determination of permissible toxic level (PTL) of return water is in introduction of ceriodaphnia Ceriodaphnia affinis Lilljeborg to control and test water, as test water return water is used, from that a set of dilutions is prepared, there ceriodaphnia are exposed during 48 hours without feeding, and at the end of exposition live ceriodaphnia are calculated, with calculation of the percent of the dead ceriodaphnia for control water, return water and dilutions of the return water, with determination of the level of toxicity of the return water through calculation of its average lethal dilution with account of coefficient found experimentally. On the basis of the results obtained for determination of the levels of acute lethal toxicity, real toxic level (RTL) of return water is calculated, that for, for each sample of return water, multiplicity of dilutions calculated, the results of dilution rate obtained are used for calculation of required dilution rate of specific samples of return water (RDRS), the last value of the required dilution rate (RDR) is calculated as arithmetical average of the set of values of the RDRS for specific samples of return water, the result of calculation of the RDR is equal to the RLT of the return water, the value of RTL obtained is used for determination of the RTL of the return water. |
