Toxicity of ionic liquids on the growth, reproductive ability, and ATPase activity of earthworm

To evaluate the toxicity of the ionic liquid 1-methyl-3-octylimidazolium bromide ([C8mim]Br) to Eisenia foetida, effects of [C8mim]Br on the growth, reproductive ability, and adenosine triphosphatase (ATPase) activity of earthworms were determined under laboratory conditions using artificial soil as substrate. The results showed that [C8mim]Br in high concentrations significantly inhibited the growth of the earthworms. These effects were enhanced with prolonged exposure to and increasing concentration of [C8mim]Br. E. foetida’s reproductive ability was significantly inhibited after 42 d of subchronic exposure to [C8mim]Br at a concentration ≥5 mg kg−1 artificial soil (dry weight). During acute exposure, a high concentration of [C8mim]Br ≥40 mg kg−1 artificial soil (dry weight) inhibited the activities of Na+–K+–ATPase and Mg++–ATPase after 3 and 7 d of exposure. After 42 d of subchronic exposure, the activity of both ATPases was inhibited in groups exposed to ≥5 mg [C8mim]Br kg−1 artificial soil (dry weight). These results indicate that treatment with the ionic liquid [C8mim]Br affects the growth, reproductive ability, and ATPase activity of earthworms E. foetida.