title: The aquatic impact of ionic liquids on freshwater organisms.
abstract: Ionic liquids (ILs), also known as liquid electrolytes, are powerful solvents with a wide variety of academic and industrial applications. Bioassays with aquatic organisms constitute an effective tool for the evaluation of ILs' toxicity, as well as for the prediction and identification of possible moieties that act as toxicophores. In this work, the acute toxicity of six ILs and two commonly used organic solvents was evaluated using freshwater organisms: Daphnia magna, Raphidocelis subcapitata and Hydra attenuata. The bioassays were performed by exposing the organisms to increasing concentrations of the ILs and observing D. magna immobilization, R. subcapitata growth inhibition, and the morphological or mortality effects in H. attenuata. The results demonstrate that the tested organisms are not equally susceptible to the ILs, e.g., bmpyr [BF4] was the least toxic compound for R. subcapitata, N1,1 [N1,1,1OOH] for D. magna and emim [Tf2N] for H. attenuata. This highlights the importance of applying a battery of assays in toxicological analysis. Additionally, Hydra proved to be the most tolerant species to the tested ILs. According to their hazard rankings, the tested ILs are considered practically harmless or moderately toxic, except (Hex)3(TDec)P [Cl], which was classified as highly toxic. The ILs were revealed to be more harmful to aquatic systems than the tested organic solvents, reaffirming the need to analyze carefully the (eco)toxicological impact of these compounds. The present study provides additional data in the evaluation of the potential hazard and the impact of ILs in the environment.
authors.affiliation: LAQV, Requimte, Departamento de Ciências Químicas, Laboratório de Química Aplicada, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto, Portugal. Electronic address: dcf20107@ff.up.pt.
authors.forename: Susana P F
authors.initials: SP
authors.lastname: Costa
authors.affiliation: LAQV, Requimte, Departamento de Ciências Químicas, Laboratório de Química Aplicada, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto, Portugal. Electronic address: ppinto@ff.up.pt.
authors.forename: Paula C A G
authors.initials: PC
authors.lastname: Pinto
authors.affiliation: LAQV, Requimte, Departamento de Ciências Químicas, Laboratório de Química Aplicada, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto, Portugal. Electronic address: lsaraiva@ff.up.pt.
authors.forename: M Lúcia M F S
authors.initials: ML
authors.lastname: Saraiva
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Caixa Postal 96, Avenida Centenário, 303, SP, Brazil. Electronic address: frprocha@cena.usp.br.
authors.forename: Fábio R P
authors.initials: FR
authors.lastname: Rocha
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Caixa Postal 96, Avenida Centenário, 303, SP, Brazil. Electronic address: joyceribeiro123@gmail.com.
authors.forename: Joyce R P
authors.initials: JR
authors.lastname: Santos
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Caixa Postal 96, Avenida Centenário, 303, SP, Brazil. Electronic address: monteiro@cena.usp.br.
authors.forename: Regina T R
authors.initials: RT
authors.lastname: Monteiro
mesh_terms: D000818:Animals; D059001:Aquatic Organisms / Q000187:drug effects*; D000460:Chlorophyta / Q000187:drug effects / Q000254:growth & development; D003621:Daphnia / Q000187:drug effects / Q000254:growth & development; D004784:Environmental Monitoring / Q000379:methods*; D005618:Fresh Water / Q000737:chemistry; D006829:Hydra / Q000187:drug effects / Q000254:growth & development; D052578:Ionic Liquids / Q000032:analysis / Q000737:chemistry / Q000633:toxicity*; D015394:Molecular Structure; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D052578:Ionic Liquids; D014874:Water Pollutants, Chemical
keywords: Daphnia magna; Hydra attenuata; Ionic liquids; Raphidocelis subcapitata; Toxicity