Changes in the biological parameters of freshwater shell Ceriodaphnia dubia Richard, 1894 under the action of lead nitrate

Fomicheva E. M., Bolshakova V. B.

The effect of lead at a concentration of 0.02 mg/l on the population indicators of Ceriodaphnia dubia depending on the age of individuals at the time of exposure to a medium with a toxicant and its effect on a number of generations of crustaceans was studied. The results of the study showed that the nature of the toxic effect, expressed in a statistically significant change in prolificacy, varies depending on the age at which the toxic effect begins on the crustaceans. When 1-day-old crustaceans are placed in a toxicant solution, a statistically significant decrease in the total number of offspring and the average number of litters per female is observed compared to the control. In the case of using mature individuals, the effect of hormesis was observed, which manifested itself in a statistically significant increase in the total number of offspring in the experiment. When studying the effect of lead on a number of generations of ceriodaphnia, an increase in the inhibitory effect was revealed, which is expressed in a statistically significant decrease in the lifespan of crustaceans and the number of offspring in subsequent generations of crustaceans.

Keywords:toxic effect, lead nitrate, Ceriodaphnia dubia, prolificacy, survival, heavy metals, hormesis, biotesting.