Ecotoxicologial assessment of cetylpyridinium chloride and 1-(2-hydroxyethyl)-3-methylimidazolium chloride

• Autor(a) principal: Pacheco, Elisabete José de Sousa
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.22/13947
• topic: Ecotoxicity; Ionic liquids; Cetylpyridinium chloride; C. vulgaris; D. magna; A. salina; L. sativa; A. cepa

Ionic liquids (ILs) are salts that are stable over their melting temperature and are made exclusively of ions (one organic cation and one organic or inorganic anion). This chemical class has received considerable interest due to their unique and tuneable properties. The growing interest in ILs predicts an increase of their manufacture and use at industrial scale, which may result in the increased release of these compounds into the environment. In the past years, ILs have been used as a greener alternative to hazardous conventional solvents, although few data regarding the toxicity and ecotoxicity of ILs is available. In the present work, we assessed the ecotoxicological profile of one imidazolium based IL, 1-(2-hydroxyethyl)-3-methylimidazolium chloride ([C2OHMIM][Cl]), and one pyridinium based IL, cetylpyridinium chloride ([C16Pyr][Cl]). The ecotoxicological evaluation was performed using a battery of test organisms from different ecosystems and from different trophic levels: Chlorella vulgaris, Daphnia magna, Artemia salina, Lactuca sativa and Allium cepa. [C16Pyr][Cl] demonstrated to be more toxic to all the test organisms than [C2OHMIM][Cl]. [C16Pyr][Cl] EC50 values varied between 0.0000205 and 35.404 mM. [C2OHMIM][Cl] EC50 values varied between 3.635 and 111.97 mM. [C16Pyr][Cl] hazard classification varied from relatively harmless for A. cepa to super toxic to D. magna. [C2OHMIM][Cl] hazard classification varied from relatively harmless for all test systems to practically nontoxic to D. magna. It was also shown that D. magna demonstrated the highest sensitivity for both ILs. The present results showed to be useful to understand ILs toxicity profile and to provide additional information for the design of safer compounds.