Instituto de Geología Aplicada, Universidad de Castilla-La Mancha, 13400 Ciudad Real, Spain.
Independent Researcher, C/Madrid 18, Puertollano, 13500 Ciudad Real, Spain.
Int J Environ Res Public Health. 2021 May 13;18(10):5191. doi: 10.3390/ijerph18105191.
The biomonitoring of atmospheric mercury (Hg) is an important topic in the recent scientific literature given the cost-benefit advantage of obtaining indirect measurements of gaseous Hg using biological tissues. Lichens, mosses, and trees are the most commonly used organisms, with many standardized methods for some of them used across European countries by scientists and pollution regulators. Most of the species used the uptake of gaseous Hg (plant leaves), or a mixture of gaseous and particulate Hg (mosses and lichens), but no method is capable of differentiating between main atmospheric Hg phases (particulate and gaseous), essential in a risk assessment. The purpose of this work was to evaluate different uptake patterns of biological tissues in terms of atmospheric Hg compounds. To accomplish this, the feasibility of two plant tissues from a tree commonly found in urban environments has been evaluated for the biomonitoring of gaseous Hg species in a Hg mining environment. Sampling included leaves and barks from and particulate matter from the atmosphere of the urban area around Almadén (south-central Spain), while analytical determinations included data for total Hg concentrations in biological and geological samples, Hg speciation data and total gaseous Hg (TGM). The results allowed us to identify the main Hg compounds in leaves and bark tissues and in atmospheric particulate matter, finding that leaves bioaccumulated only gaseous Hg (Hg and Hg), preferably during daylight hours, whereas the barks accumulated a combination of TGM and particulate bound Hg (PBM) during the day and at night. Subsequent merging of the atmospheric Hg speciation data obtained from leaves and barks allowed indicative maps of the main sources of TGM and PBM emissions to be obtained, thereby perfectly delimiting the main TGM and PBM sources in the urban area around Almadén. This method complements TGM biomonitoring systems already tested with other urban trees, adding the detection of PBM emission sources and, therefore, biomonitoring all Hg species present in the atmosphere. Scenarios other than mining sites should be evaluated to determine the utility of this method for Hg biospeciation in the atmosphere.
大气汞（Hg）的生物监测是近期科学文献中的一个重要议题，因为利用生物组织间接测量气态 Hg 具有成本效益优势。地衣、苔藓和树木是最常用的生物体，欧洲国家的科学家和污染监管机构已经针对其中一些生物体制定了许多标准化方法。大多数使用的物种是通过植物叶片吸收气态 Hg（植物叶片），或通过混合气态和颗粒态 Hg（苔藓和地衣）来吸收，但没有一种方法能够区分大气 Hg 的主要相（颗粒态和气态），这在风险评估中至关重要。本工作的目的是评估生物组织在大气 Hg 化合物方面的不同吸收模式。为此，评估了一种常见于城市环境中的树木的两种植物组织，用于在汞矿区监测气态 Hg 物种。采样包括来自 和大气中的颗粒物，而分析测定包括生物和地质样本中的总 Hg 浓度、Hg 形态数据和总气态 Hg（TGM）数据。结果使我们能够确定叶片和树皮组织以及大气颗粒物中的主要 Hg 化合物，发现叶片仅生物积累气态 Hg（Hg 和 Hg），最好在白天进行，而树皮在白天和夜间积累 TGM 和颗粒结合 Hg（PBM）的混合物。随后将从叶片和树皮中获得的大气 Hg 形态数据进行合并，从而可以获得 TGM 和 PBM 排放的主要来源指示性地图，从而完美地确定了阿尔马登周围城市地区的主要 TGM 和 PBM 来源。这种方法补充了已经用其他城市树木进行测试的 TGM 生物监测系统，增加了对 PBM 排放源的检测，因此可以对大气中存在的所有 Hg 物种进行生物监测。应该评估除矿区以外的其他场景，以确定该方法在大气 Hg 生物形态分析中的效用。
