Assessing chemical toxicity of ionic liquids on Vibrio fischeri: Correlation with structure and composition

Abstract

One of the most important properties of the ionic liquids (ILs) is their non-volatility. However, they are wide soluble in water. For this reason, they can be released to aquatic ecosystems and to contribute to water pollution. Nevertheless, toxicological data related to ionic liquids is scarce in literature because of the great number of possible ionic liquids synthesized. The present work reports the toxicity of twenty-nine imidazolium-, pyridinium- and ammonium-based ionic liquids towards the luminescent bacteria Vibrio fischeri. Some of the effects analyzed on the toxicity have been the type of anion, the length of the alkyl chain of the cation, the cation core and the presence of a functionalized side chain in the cation. These results have showed that the main influence on the toxicity of the ILs is the alkyl chain length. A Quantitative Structure-Activity Relationships (QSAR) method has been used to validate our results obtaining a very good agreement.