Unraveling the ecotoxicity of deep eutectic solvents using the mixture toxicity theory.

This study evaluates the ecotoxicological profile of DES based on [N1111]Cl, [N2222]Cl and [N3333]Cl as hydrogen bond acceptors (HBA) combined with hydrogen-bond donors (HBD) vis. ethylene glycol and 1-propanol, through the Microtox® Acute Toxicity Test. CA and IA with deviations describing synergism/antagonism, dose-ratio and dose-level effects were fitted to the toxicity data. Neither the starting materials nor DES were found hazardous to Aliivibrio fischeri, in this specific case agreeing with the claimed "green character" of DES. Among the starting materials, ethylene glycol was the least toxic, whereas [N3333]Cl was the most toxic (30 min-EC50 = 96.49 g L-1 and 0.5456 g L-1, respectively). DES toxicity followed the same trend as observed for the salts: [N1111]Cl-based DES < [N2222]Cl-based DES < [N3333]Cl-based DES. The IA model, with specific deviations, adjusted better in 5 out of 6 DES. Antagonism was observed for [N1111]Cl-based DES, and synergism for [N3333]Cl-based DES and for 1-propanol:[N2222]Cl. The application of the mixture toxicity models represents a breakthrough in the problematic of assessing the toxicity of the countless number of DES that can be created with the same starting materials, since they provide the expected toxicity of any virtual combination between HBA and HBD.
PMID: 30195169 [PubMed - indexed for MEDLINE]

Source: Chemosphere - November 9, 2018 Category: Chemistry Authors: Macário IPE, Jesus F, Pereira JL, Ventura SPM, Gonçalves AMM, Coutinho JAP, Gonçalves FJM Tags: Chemosphere Source Type: research