Abstract:
Bismuth (Bi) is considered a \"green metal\" as its toxicity has been reported to be lower than other metals, particularly lead. Even though the low presence in the environment, an increase of Bi concentrations in soil and wastewater is predictable due to its enhanced uses for many industrial and medical applications. Therefore, given the little literature on the matter, particularly in plants, information on the effects of Bi on living organisms is needed. In this study, seeds of garden cress (Lepidium sativum L.), a model plant for ecotoxicological assays (OECD), were exposed to increasing Bi concentrations (0 to 485 mg L-1 Bi(NO3)3·5H2O in deionised water) in petri plates. After 72 h, the percent germination index (GI%) revealed no effects at the lowest Bi concentrations, while a slight toxicity occurred at 242 and 485 mg L-1 Bi nitrate. A significant reduction of the root length was observed in Bi-treated seedlings, especially at the highest Bi concentrations. Consistently, the Alkaline Comet Assay revealed a genotoxic effect induced by Bi exposure in garden cress seedlings. A Bi concentration-dependent metal accumulation in plantlets was also observed, with a Bi concentration higher than 1200 mg kg-1 found in plantlets at the highest Bi concentration assayed. The toxicity effects observed in the study were discussed, as contribution to the expansion of knowledge on Bi ecotoxicity and genotoxicity in plants.
摘要:
铋(Bi)被认为是“绿色金属”,因为据报道其毒性低于其他金属,尤其是铅。即使在环境中的低存在,土壤和废水中Bi浓度的增加是可预测的,因为它在许多工业和医疗应用中的用途得到了提高。因此,鉴于关于这件事的文献很少,特别是在植物中,需要有关Bi对生物体影响的信息。在这项研究中,豆瓣菜种子(LepidiumsativumL.),生态毒理学分析的模型植物(OECD),在培养皿中暴露于不断增加的Bi浓度(去离子水中的0至485mgL-1Bi(NO3)3·5H2O)。72小时后,发芽指数百分比(GI%)显示在最低Bi浓度下没有影响,而在242和485mgL-1硝酸铋时发生轻微毒性。在Bi处理的幼苗中观察到根长的显着减少,尤其是在Bi浓度最高的时候.始终如一,碱性彗星试验揭示了田芹幼苗中Bi暴露引起的遗传毒性作用。还观察到小植株中Bi浓度依赖性金属积累,在测定的最高Bi浓度下,小植株中的Bi浓度高于1200mgkg-1。讨论了研究中观察到的毒性效应,有助于扩大植物中Bi生态毒性和遗传毒性的知识。