Ionic liquids (ILs) are acknowledged as green chemicals and favorable substitutes for volatile organic solvents, which are currently used. However, previous studies have shown that these compounds had toxicological impacts on aquatic organisms. To investigate the effects of 1-hexyl-3- methylimidazolium bromide ionic liquid ([C6mim]Br) on embryonic development and reproduction in water flea (Daphnia magna), a series of exposure experiments were conducted, including acute toxicity, maternal exposure, and chronic exposure tests. In acute toxicity experiment, D. magna neonates exhibited developmental abnormalities in the shell spine and the second antennae in a concentration-dependent manner after exposure to [C6mim]Br. The results in maternal exposure test also revealed a certain embryo-toxicity in response to [C6mim]Br in D. magna. However, the toxicity was lower than that conveyed by direct acute exposure, this indicated that the IL could act directly on organism. During the 21 days chronic exposure, the 1.6 mg/L exposure caused marked drop in the survival, molts and the number of the first brood of D. magna. Meanwhile, the total number of offspring was significantly declined in 1.6 mg/L concentration treatment groups, whereas increased in 0.2 mg/L groups. Generally, abnormalities in the offspring were significantly increased across all of the treatment groups in contrast to the control. No effect on sex differentiation was found during the experiments. These findings suggested that [C6mim]Br could affect embryonic development and reproduction in D. magna, and provided references for further study on the mechanisms underlying toxicological effects of ILs and the assessment of their potential environmental risks.

中文翻译：

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1-己基-3-甲基咪唑鎓溴化物对大型蚤的胚胎发育和繁殖的影响。

离子液体（ILs）被公认为是绿色化学品，是目前使用的挥发性有机溶剂的有利替代品。但是，以前的研究表明这些化合物对水生生物具有毒理学影响。为了研究1-己基-3-甲基咪唑鎓溴化物离子液体（[C6mim] Br）对水蚤（Daphnia magna）胚胎发育和繁殖的影响，进行了一系列暴露实验，包括急性毒性，母体暴露和慢性暴露测试。在急性毒性实验中，暴露于[C6mim] Br的新生小D虾在壳棘和第二触角中呈发育异常，呈浓度依赖性。孕产妇接触试验的结果还表明，对D. magna中的[C6mim] Br有一定的胚胎毒性。然而，毒性低于直接急性暴露所传递的毒性，这表明IL可以直接作用于生物体。在21天的长期接触中，1.6 mg / L的接触导致D. magna的存活率，蜕皮和第一个亲代数显着下降。同时，在1.6 mg / L浓度的治疗组中，后代总数显着下降，而在0.2 mg / L的治疗组中，后代总数明显增加。一般而言，与对照组相比，所有治疗组的后代异常率均显着增加。实验期间未发现对性别分化的影响。这些发现表明[C6mim] Br可能会影响D. magna的胚胎发育和繁殖，