Programa de Pós-Graduação em Ciências Ambientais, Centro de Estudos em Limnologia, Biodiversidade e Etnobiologia do Pantanal, Universidade do Estado de Mato Grosso, Cáceres, Brazil.
Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Barcelona, Spain.
Arch Environ Contam Toxicol. 2023 Jul;85(1):34-45. doi: 10.1007/s00244-023-01009-x. Epub 2023 Jun 24.
Mercury is a global contaminant found in the Amazon; it can be biomagnified in the aquatic trophic chain. The use of piscivorous birds for biomonitoring of mercury contamination is increasing, mainly due to the non-mobility of mercury in bird feathers. We examined the concentrations of total mercury and methylmercury in different tissues of the green kingfisher, Chloroceryle americana collected from the Teles Pires and Juruena Rivers in the southern Brazilian Amazon. We also evaluated total mercury in small Characidae fish (potential C. americana food) in the same areas. The results indicate contamination of the birds with high concentrations, on average two-times higher in the green kingfishers from the Teles Pires River compared to the Juruena River; the same results were found for the fish specimens. Fifty-eight per cent of the feather samples from the Juruena River and 90% from the Teles Pires River had total mercury concentrations above 5 µg/g, a level previously associated with adverse effects related to bird breeding. The methylmercury concentration was lowest in the liver, followed by feathers and highest in muscle. Although Juruena River bird feathers had a lower total mercury concentration, > 96% of the total mercury was methylmercury, the highest amount for specimens from both rivers. Although the concentration of Hg in the muscle of the green kingfisher is higher when compared to the feather and liver, the non-invasive monitoring through analysis of samples of feathers is an efficient biomonitoring tool for evaluation of mercury contamination in tropical birds.
汞是在亚马逊地区发现的一种全球性污染物，它可以在水生营养链中被生物放大。利用食鱼鸟类来监测汞污染的情况正在增加，这主要是由于汞在鸟类羽毛中不易移动。我们检测了来自巴西亚马逊南部 Teles Pires 和 Juruena 河流的绿鱼狗的不同组织中总汞和甲基汞的浓度。我们还评估了同一地区的小型脂鲤科鱼类（绿鱼狗的潜在食物）中的总汞含量。结果表明，这些鸟类受到了高浓度的污染，与来自 Juruena 河的绿鱼狗相比，来自 Teles Pires 河的绿鱼狗体内的汞浓度平均高出两倍；鱼类标本也出现了同样的结果。来自 Juruena 河的 58%的羽毛样本和来自 Teles Pires 河的 90%的羽毛样本的总汞浓度超过了 5μg/g，这一水平以前与鸟类繁殖的不良影响有关。甲基汞的浓度在肝脏中最低，其次是羽毛，在肌肉中最高。尽管 Juruena 河鸟类的羽毛总汞浓度较低，但>96%的总汞为甲基汞，这是两条河流标本中含量最高的。尽管与羽毛和肝脏相比，绿鱼狗肌肉中的汞浓度更高，但通过分析羽毛样本进行非侵入性监测是评估热带鸟类汞污染的有效生物监测工具。
