Departamento de Biologia & CESAM, Universidade de Aveiro, 3810-193 Aveiro, Portugal.
Dipartimento di Scienze Veterinarie, Università di Pisa, Italy; Consorzio per il Centro Interuniversitario di Biologia Marina ed Ecologia Applicata "G. Bacci" (CIBM), Livorno, Italy.
Sci Total Environ. 2020 Jul 1;724:138143. doi: 10.1016/j.scitotenv.2020.138143. Epub 2020 Mar 23.
Ocean acidification and warming are among the man-induced factors that most likely impact aquatic wildlife worldwide. Besides effects caused by temperature rise and lowered pH conditions, chemicals of current use can also adversely affect aquatic organisms. Both climate change and emerging pollutants, including toxic impacts in marine invertebrates, have been investigated in recent years. However, less information is available on the combined effects of these physical and chemical stressors that, in nature, occur simultaneously. Thus, this study contrasts the effects caused by the antimicrobial agent and plastic additive, Triclosan (TCS) in the related clams Ruditapes philippinarum (invasive) and Ruditapes decussatus (native) and evaluates if the impacts are influenced by combined temperature and pH modifications. Organisms were acclimated for 30 days at two conditions (control: 17 °C; pH 8.1 and climate change scenario: 21 °C, pH 7.7) in the absence of the drug (experimental period I) followed by a 7 days exposure under the same water physical parameters but either in absence (unexposed) or presence of TCS at 1 μg/L (experimental period II). Biochemical responses covering metabolic, oxidative defences and damage-related biomarkers were contrasted in clams at the end of experimental period II. The overall picture showed a well-marked antioxidant activation and higher TCS bioaccumulation of the drug under the forecasted climate scenario despite a reduction on respiration rate and unaltered metabolism in the exposed clams. Since clams are highly consumed shellfish, the consequences for higher tissue bioaccumulation of anthropogenic chemicals to final consumers should be alerted not only at present conditions but more significantly under predicted climatic conditions for humans but also for other components of the marine trophic chain.
海洋酸化和变暖是人为因素中最有可能影响全球水生野生动物的两个因素。除了温度升高和 pH 值降低带来的影响外，目前使用的化学物质也会对水生生物产生不利影响。近年来，人们一直在研究气候变化和新兴污染物，包括对海洋无脊椎动物的毒性影响。然而，关于这些物理和化学胁迫因素同时发生的综合影响的信息较少。因此，本研究对比了抗菌剂和塑料添加剂三氯生（TCS）在相关贻贝菲律宾蛤仔（入侵种）和褶牡蛎（本地种）中引起的影响，并评估了这些影响是否受到温度和 pH 值联合变化的影响。在实验期间 I，将生物体在两种条件下（对照：17°C；pH 8.1 和气候变化情景：21°C，pH 7.7）适应 30 天，然后在相同的水物理参数下暴露 7 天，但药物不存在（未暴露）或存在 1μg/L 的 TCS（实验期间 II）。在实验期间 II 结束时，对比了贻贝的代谢、氧化防御和与损伤相关的生物标志物等生化反应。总体情况表明，尽管暴露组的呼吸速率降低，代谢未改变，但在预测的气候情景下，抗氧化剂的激活和药物 TCS 的生物积累更为明显。由于贻贝是高消费的贝类，因此不仅要在当前条件下，而且要在预测的人类气候条件下，对最终消费者体内更高的人为化学物质组织生物积累的后果保持警惕，还要对海洋食物链的其他组成部分保持警惕。
