resumo
The design of environmentally friendlier solvents has gained increasing relevance in the last decade. Deep eutectic solvents (DES) have recently emerged, with advantages like low-cost and putative lower environmental impact. However, information about DES toxicity is still scarce. This work aims to contribute to profiling the ecotoxicity of DES based on cholinium chloride ([Chol]Cl). Six DES were addressed, combining [Chol]Cl (as hydrogen bond acceptor HBA) with ethylene glycol, glycerol, 1,2-propanediol, propionic acid, 1-propanol, and urea as hydrogen bond donors (HBD), in different molar ratios. The Microtox (R). Acute Toxicity Test, was used for assessing their toxicity towards the marine bacteria Allivibrio fischeri. Because the dissociation of DES in water is expected, analysis appraising the mixtures toxicity theory should be considered, which is a step forward in this field. This analysis suggested that [Chol]Cl and all HBD with the exception of propionic acid:[Chol]Cl 1:2 and 4:1 behave antagonistically, which is contrary to what has been suggested previously. The most extreme cases are Urea: [Chol]Cl and 1-Propanol:[Chol]Cl, with EC50 values higher than their starting materials dosed singly, configuring very promising and biocompatible alternative solvents. Toxicity was found to be dependent on DES composition, as well as on molar proportions of the starting materials.
palavras-chave
AQUEOUS BIPHASIC SYSTEMS; CLASSIFYING ENVIRONMENTAL-POLLUTANTS; TOXICITY; CHLORIDE; MIXTURES; WATER; BIODEGRADABILITY; CYTOTOXICITY; EXTRACTION; ALCOHOLS
categoria
Environmental Sciences & Ecology; Toxicology
autores
Macario, IPE; Ventura, SPM; Pereira, JL; Goncalves, AMM; Coutinho, JAP; Goncalves, FJM
nossos autores
Inês Adriana Patrunilho Efe Macário
Estudante de doutoramento
Sónia Patrícia Marques Ventura
Professor AuxiliarProjectos
CICECO - Aveiro Institute of Materials (UID/CTM/50011/2013)
Projeto de Investigação Exploratória: Sónia Patricia Marques Ventura (IF/00402/2015)
agradecimentos
Thanks are due for the financial support to CESAM (ref. FCT UID/AMB//50017/2013) by FCT - Portuguese Foundation for Science and Technology/MCTES - Ministry of Science (MEC), Portugal, with the co-funding by the FEDER, Europe, within the PT2020 Partnership Agreement and Compete 2020. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. The authors also thank FCT for the project PTDC/ATP-EAM/5331/2014, the doctoral grant of IPE Macario (SFRH/BD/123850/2016) and post-doctoral grants of AMM Gonsalves and JL Pereira (SFRH/BPD/97210/2013, SFRH/BPD/101971/2014), respectively. SPM Ventura acknowledges FCT for the contract IF/00402/2015 under the Investigador FCT 2015 program.