Estudo da toxicidade de líquidos iônicos carboxilados frente a Artemia salina

Abstract

Ionic liquids (ILs) are organic salts formed from the combination of a cation and an anion that exhibit unique specific characteristics. They have a melting point of less than 100°C, good ionic conductivity, negligible vapor pressure and high thermal stability. As ILs indicate a great potential for several industrial applications, they have been increasingly studied and inserted in different types of processes, acting as solvents and catalysts. However, since there is a variation in their toxic effects, so that their disposal and use in industrial processes will not cause damage, it is necessary to know about their toxicity. In this work, acid bromide 2-(3-metilimidazolil-1-iletoxi-4-oxobutanóico) e do acid bromide 2-((2-(3-metilimidazolio-1-il)etoxi)carboil)benzoico ionic liquids were produced, and the toxicity of different concentrations (3.1% to 100%) was evaluated for the microcrustacean bioindicator Artemia salina, using the immobility/mortality test. From the synthesis of the ionic liquids, the production yield of 87.0% for acid bromide 2-(3-metilimidazolil-1-iletoxi-4-oxobutanóico) and 86.7% for acid bromide 2-((2-(3-metilimidazolio-1-il)etoxi)carboil)benzoico was verified. After performing the toxicological bioassays, it was concluded that both ionic liquids were toxic to A. salina, resulting in a mortality rate of 100% of the test organisms at all tested concentrations. This toxicity may be due to the low pH of the ILs in the treatment solution (ranging from 3.0 to 6.0) and because they are very viscous at room temperature, making locomotion difficult for the nauplii. Thus, it is suggested further toxicity tests with these ILs, with other bioindicators and biomarkers.