Toxicological effect of essential oils of plants against Artemia salina

The present study was carried out with the objective of assessing the acute toxicity of four essential plant oils against the brine shrimp lethality bioassay. The essential oils were dissolved in dimethyl sulfoxide (DMSO) at 1 % and concentrations at 0.01; 0.05; 0.25; 1.25; 6.25 and 31.25 µg/ml were prepared which were added in microcells of 96 dishes containing from 10 to 15 nauplii of Artemia salina in saline solution with a total volume of 150 µL. Each concentration was replicated 8 times. Two controls were used, one with saline water solution containing 38 g of coarse salt/l and the other with DMSO 1 % solvent dissolved in the saline solution. Samples were maintained with light and at environmental temperature. Larvae death on exposing them to contact for 24 h was counted. The Lethal Concentration 50 (LC50) was determined by the Probit method using the statistical package SPSS, version 22. All essential oils tested manifested a high acute toxicity at low dosages. These showed high lethality and its results followed by order of toxicity were: Cymbopogon citratus (LC50= 1.212 µg/ml) >Lippia rotundifolia (LC50= 1.256 µg/ml) >Lippia origanoides (LC50= 1.267 µg/ml) >Cymbopogon citratus Lemon-Grass© (LC50= 1.284 µg/ml). It is concluded that given the lethality exhibited by the essential oils of Cympogogon citratus Lemon-Grass©, C.citratus, Lippia origanoides and Lippia rotundifolia against the Artemia salina micro-crustaceous can be considered promissory essential oils for its use for the control of harmful organisms. Other more specific studies are recommended for demonstrating its biological activity.