Abstract:
Most of the electric and electronic waste is not recycled and the release of its components into the environment is expected, including the rare-earth element Lanthanum (La), which has already been reported in the aquatic systems. Furthermore, considering climate change factors such as the predicted increase in temperature, the susceptibility of aquatic organisms to these rare elements may be modified. In light of this, the present study aimed to evaluate the relevance of temperature on La-derived effects in the mussel Mytilus galloprovincialis. Several biomarkers and La bioaccumulation were assessed in organisms exposed to 0 (control) and 10 μg/L of La at two distinct temperatures (17 and 22 °C) for 28 days. Results showed that temperature did not influence La bioaccumulation in mussels. However, exposure to La resulted in a decreased metabolic capacity and an enhancement of biotransformation enzymes activity, as a possible defense behavior of mussels to avoid La accumulation and toxicity. Nevertheless, antioxidant defenses were also inhibited leading to increased lipid peroxidation (LPO) levels. Warming alone seemed to cause a metabolic shutdown seen as reduced enzyme activities and protein carbonylation (PC) levels. Simultaneous La exposure and temperature rise caused combined effects on mussels, as they accused metabolic depression, biotransformation defenses activation, antioxidant capacity reduction, and higher cellular damage. Overall, this study highlights the need to perform environmental risk assessment studies, by considering emerging contaminants exposures at relevant concentrations, both at present and forecasted climate change scenarios.
摘要:
大部分的电气和电子废物没有被回收利用,其成分预计会释放到环境中,包括稀土元素镧(La),这在水生系统中已经有报道。此外,考虑到气候变化因素,如预测的温度升高,水生生物对这些稀有元素的敏感性可能会改变。鉴于此,本研究旨在评估温度对贻贝中La衍生作用的相关性。在两个不同温度(17和22°C)下暴露于0(对照)和10μg/LLa的生物体中评估了几种生物标志物和La的生物积累。结果表明,温度不影响贻贝中La的生物积累。然而,暴露于La导致代谢能力降低和生物转化酶活性增强,作为贻贝的一种可能的防御行为,以避免La的积累和毒性。然而,抗氧化剂防御也被抑制,导致脂质过氧化(LPO)水平增加。仅变暖似乎会导致代谢中断,这被视为酶活性和蛋白质羰基化(PC)水平降低。La同时暴露和温度升高会对贻贝产生综合影响,当他们指责代谢抑郁症时,生物转化防御激活,抗氧化能力降低,和更高的细胞损伤。总的来说,这项研究强调了进行环境风险评估研究的必要性,通过考虑在相关浓度下出现的污染物暴露,目前和预测的气候变化情景。