Programa de Pós-Graduação em Ciências Biológicas-Fisiologia, Instituto de Ciências Básicas da Saúde, Departamento de Farmacología, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Ecotoxicol Environ Saf. 2012 Oct;84:319-24. doi: 10.1016/j.ecoenv.2012.08.001. Epub 2012 Aug 19.
The decomposition of solid waste in landfill is responsible for the formation of leachate, a dark liquid with an unpleasant odor; studies investigating its toxicity on mammals are rare. Oxidative stress has been considered as an important biochemical mechanism of the toxicity of several xenobiotics. The aim of this study was to evaluate the effects of landfill leachate on oxidative parameters in striatum, hippocampus and liver homogenates of mice and rats. In order to propose a clean technology for the treatment of leachate, we also investigated the effects of landfill leachate submitted to photoelectrooxidation process (PEO). The homogenates of cerebral structures and liver of Swiss albino mice and Wistar rats were incubated with different concentrations of non-PEO landfill leachate and PEO-treated landfill leachate. After the incubation, the levels of free radicals, determined by 2',7'-dichlorofluorescein diacetate probe, and the lipoperoxidation, quantified by the thiobarbituric acid reactive substances, were evaluated. There was an increase on the levels of free radicals in striatum of both mice and rats when exposed to non-PEO leachate. Moreover, PEO-treated leachate increased the lipoperoxidation in striatum homogenates from rodents. However, both leachates did not alter any of the parameters evaluated in the hippocampus. In the liver, the incubation with leachates induced an augment on levels of free radicals only in samples of mice. In addition, PEO-treated leachate increased the lipoperoxidation indexes in the liver of mice and rats. These results suggest that the landfill leachate can induce an oxidative stress state in the liver and the striatum of rodents. Additionally, the PEO process was unable to efficiently alter the toxic compounds of landfill leachate.
垃圾填埋场中的固体废物分解会产生渗滤液，这是一种恶臭的深色液体；研究哺乳动物对其毒性的研究很少。氧化应激被认为是几种外源性化学物质毒性的重要生化机制。本研究旨在评估垃圾渗滤液对小鼠和大鼠纹状体、海马和肝匀浆氧化参数的影响。为了提出一种处理渗滤液的清洁技术，我们还研究了经光电氧化（PEO）处理的渗滤液的影响。用不同浓度的未经 PEO 处理的垃圾渗滤液和经 PEO 处理的垃圾渗滤液孵育瑞士白化小鼠和 Wistar 大鼠的脑结构和肝匀浆。孵育后，用 2'，7'-二氯荧光素二乙酸探针测定自由基水平，并通过硫代巴比妥酸反应物质定量测定脂质过氧化。当暴露于未经 PEO 处理的渗滤液时，两种动物的纹状体中的自由基水平均增加。此外，经 PEO 处理的渗滤液增加了啮齿动物纹状体匀浆中的脂质过氧化。然而，两种渗滤液均未改变海马中评估的任何参数。在肝脏中，只有在小鼠的样本中，孵育渗滤液才会引起自由基水平的增加。此外，PEO 处理的渗滤液增加了小鼠和大鼠肝脏的脂质过氧化指数。这些结果表明，垃圾渗滤液可诱导啮齿动物的肝脏和纹状体产生氧化应激状态。此外，PEO 工艺无法有效地改变垃圾渗滤液中的有毒化合物。
