Avian Ecophysiology Unit, Department of Vertebrate Ecology & Zoology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
Institute of Biology, Pedagogical University of Krakow, Podchorążych 2, 30-084 Krakow, Poland.
Sci Total Environ. 2020 Mar 25;710:136292. doi: 10.1016/j.scitotenv.2019.136292. Epub 2019 Dec 26.
Lead is one of the non-essential metals that can become a serious environmental threat to the human population and wildlife causing various toxic impairments and pathologies. Waterfowl are especially sensitive to lead exposure as they stay in areas with a high risk of lead pollution due to hunting and fishing pressures. This study aims to determine recent blood lead levels in 45 live mute swans in the southern Baltic, in the Gulf of Gdańsk and to test the hypothesis that birds with elevated lead levels have a higher physiological stress. Mean concentration of lead in blood was 0.239 μg/g (range 0.028-0.675 μg/g). Almost half of the individuals examined in this study had increased blood Pb levels above the threshold level (0.23 μg/g), however none of them showed behavioural signs of Pb poisoning. Although the dominant food of mute swans staying at municipal beaches is bread delivered by people, which has low lead levels, lead was found in all blood samples taken from mute swans. In the study area, another possible source of lead poisoning, other than from ammunition, is connected with various anthropogenic activities, such as municipal sewage works. Moreover, poor diet results in greater susceptibility to absorption of lead and this may have an additional influence on elevated lead levels in blood of these birds. The Pb level was increased with heterophils to lymphocytes (H/L) ratio, which is used as a measure of longer-term physiological stress. The mean lead level in blood was higher in young birds than in adults, which may be a consequence of adults forcing them to take less calorific food from water plants containing elevated levels of lead in the area studied. However, it is difficult to disentangle this from other factors that may influence sensitivity to lead poisoning.
铅是一种非必需的金属，它可能对人类和野生动物的环境造成严重威胁，导致各种有毒损害和病变。水禽对铅暴露特别敏感，因为它们由于狩猎和捕鱼的压力而留在高铅污染风险的区域。本研究旨在确定波罗的海南部、格但斯克湾的 45 只活默氏䴙䴘的近期血液铅水平，并检验鸟类中铅含量升高与更高生理压力相关的假设。血液中铅的平均浓度为 0.239μg/g（范围为 0.028-0.675μg/g）。在本研究中检查的近一半个体的血液 Pb 水平升高超过了阈值（0.23μg/g），但它们均未表现出铅中毒的行为迹象。尽管栖息在市政海滩上的默氏䴙䴘的主要食物是人们投喂的面包，其铅含量较低，但从默氏䴙䴘采集的所有血液样本中都发现了铅。在研究区域，除弹药外，另一个可能导致铅中毒的来源与各种人为活动有关，例如城市污水处理厂。此外，不良的饮食会导致对铅的吸收更容易，这可能会对这些鸟类血液中的铅含量升高产生额外影响。血液中铅的含量与异嗜性白细胞与淋巴细胞（H/L）比值升高有关，该比值可作为长期生理压力的衡量标准。幼鸟的血液铅水平高于成鸟，这可能是因为成鸟迫使它们从水中植物中摄取较少的热量，而这些植物在研究区域中含有较高水平的铅。但是，很难将其与可能影响铅中毒敏感性的其他因素区分开来。
