Comparative toxicities of five herbicides on nauplii of Artemia franciscana as an ecotoxicity bioindicator

Artemia is one of the most important test organisms available for ecotoxicity test. In this study the toxicity of five widely used herbicides formulations including: Paraquat, 2,4-dichlorophenoxy acetic acid (2,4-D), Trifluralin, Glyphosite and Atrazin were compared using ecotoxicity bioindicator, Artemia franciscana. Acute toxicity (48 h LC50) of five herbicides were determined via OECD standard method. Artemia were hatched via standard method and 12 h old nauplii were used for toxicity evaluation of herbicides. Naupliis  exposed to Serial concentrations (more than 6 in triplicates) of each herbicid.  Mortalities at 12, 24, 36 and 48 hours after exposure were recorded and the LC50 were calculated using Probit software. Results showed that the mortality rate increased along with increasing the exposure time in all herbicide toxicity assays. Besides 48 hours LC50 value of Paraquat, 2,4-D, Trifluralin, Glyphosite and Atarzine calculated at 15.67, 12.93, 11.87, 164.31 and 61.34 mg/L in A. franciscana respectively. Glyphosate showed significantly lesser lethality and toxicity while Trifluralin and 2,4-D showed the highest toxicity in  A. franciscana among the examined herbicides. Then for sustainable agricultural activity, especially in areas that runoff water flow to aquatic  ecosystems, it is highly recommended to use environmental friendly herbicides like glyphosate as an alternative to highly toxic herbicides like trifluralin, Paraquat and 2,4-D. To the best of our knowledge, this work is the first study comparing the toxicity of highly used herbicides using  ecotoxicity bioindicator, Artemia franciscana.