Demography and life cycle of Daphnia Magna, subjected to the toxicity of andiroba oil used as a natural repelente

Abstract

Daphnia magna is a common model organism used in toxicological testing because it is widely distributed in aquatic environments, has a short life cycle and is easy to rear in the laboratory. For the cultivation of cladocerans and for experiments, natural water and algae of the species Chlorella sorokiniana was used as diet. For Daphnia culture, modified EPA medium was used. And the general experimental conditions were: 50 mL transparent bottles, in a 1:1 ratio, of medium water and test substance, in treatments and control with medium water, where each test bottle received 10 neonates (<24 h) from the test organism, Daphnia magna. Calculations related to demographic analysis were determined, such as average lifespan, life expectancy, gross reproduction rate, net reproduction rate, generation time and intrinsic population growth rate. In general, the toxicity of andiroba oil promoted mortality in Daphnia magna compared to the control, regardless of any concentration tested. The fertility patterns of D. magna showed a decrease in the production of neonates with increasing andiroba oil concentration. The results of the experiment indicated that andiroba oil had toxic effects on Daphnia magna, being important to evaluate the safety of this chemical product, contributing significantly to the understanding of the risks associated with its use.