Ionic Liquids Lose their Green Stripes

Despite being heralded as the green alternative to noxious, toxic, inflammable volatile organic compounds, room temperature ionic liquids are slowly losing their green stripes. In a paper published in the journal Green Chemistry (2006, 8, 238-240), Italian researchers report the acute toxicity of these compounds to zebra fish.

Luigi Intorre of the University of Pisa and colleagues, explain that although interest in ionic liquids because of claimed environmental safety is on the increase, these very good non-volatile solvents, could have harmful effects on certain ecosystems nevertheless.

The team has assessed the acute toxicity towards zebrafish of several ionic liquids with different anions and cations and found that toxic effects depended on the specific structure of the ionic liquid. However, the overall effect is potentially fatal harm to the fish’s gills.

This publication comes in the wake of earlier revelations that ionic liquids, although purportedly non-volatile, can indeed be distilled, according to a C&EN report.

Having said all that, ionic liquids still present a potentially “greener” alternative, if handled and disposed of safely, than many of the volatile organic solvents used in industry.

Research Blogging IconPretti, C., Chiappe, C., Pieraccini, D., Gregori, M., Abramo, F., Monni, G., & Intorre, L. (2006). Acute toxicity of ionic liquids to the zebrafish (Danio rerio) Green Chemistry, 8 (3) DOI: 10.1039/b511554j