Department of Earth Science, University of Florence, Via G. La Pira 4, 50121, Florence, Italy.
Department of Earth Science, University of Pisa, Via Santa Maria 53, 56126, Pisa, Italy.
Environ Sci Pollut Res Int. 2023 Dec;30(59):124232-124244. doi: 10.1007/s11356-023-31105-3. Epub 2023 Nov 24.
Biomonitoring studies are often employed to track airborne pollutants both in outdoor and indoor environments. In this study, the mercury (Hg) sorption by three biomonitors, i.e., Pinus nigra bark, Pseudovernia furfuracea lichen, and Hypnum cupressiforme moss, was investigated in controlled (indoor) conditions. In comparison to outdoor environments, controlled conditions offer the opportunity to investigate more in detail the variables (humidity, temperature, pollutants speciation, etc.) that control Hg uptake. The biomonitors were exposed in two distinct periods of the year for 2 and 12 months respectively, in the halls of the Central Italian Herbarium (Natural History Museum of the University of Florence, Italy), which are polluted by Hg, due to past plant sample treatments. The Hg sorption trend was monitored every 3 weeks by recording: (i) the Hg content in the substrata, (ii) gaseous elemental mercury (GEM) concentrations in the exposition halls, (iii) temperature, (iv) humidity, and (v) particulate matter (PM) concentrations. At the end of the experiment, Hg concentrations in the biomonitors range from 1130 ± 201 to 293 ± 45 μg kg (max-min) in barks, from 3470 ± 571 to 648 ± 40 μg kg in lichens, and from 3052 ± 483 to 750 ± 127 μg kg in mosses. All the biomonitors showed the highest Hg accumulation after the first 3 weeks of exposure. Mercury concentrations increased over time showing a continuous accumulation during the experiments. The biomonitors demonstrated different Hg accumulation trends in response to GEM concentrations and to the different climatic conditions (temperature and humidity) of the Herbarium halls. Barks strictly reflected the gaseous Hg pollution, while lichen and moss accumulation was also influenced by the climatic conditions of the indoor environment. Mercury bound to PM seemed to provide a negligible contribution to the biomonitors final uptake.
生物监测研究常用于追踪户外和室内环境中的空气污染物。本研究采用三种生物监测器（黑松树皮、假木贼地衣和垂枝藓），在控制（室内）条件下研究了它们对汞（Hg）的吸附作用。与户外环境相比，控制条件可以更详细地研究控制 Hg 吸收的变量（湿度、温度、污染物形态等）。生物监测器在意大利佛罗伦萨大学自然历史博物馆（意大利中央植物标本馆）的展厅中分别暴露了两个不同的时间段：2 个月和 12 个月，这些展厅受到 Hg 的污染，因为过去对植物样本进行了处理。每隔 3 周监测一次 Hg 吸附趋势，记录以下内容：（i）基质中的 Hg 含量，（ii）展厅中气态元素汞（GEM）的浓度，（iii）温度，（iv）湿度和（v）颗粒物（PM）浓度。实验结束时，生物监测器中的 Hg 浓度范围为：树皮中 1130±201 至 293±45μgkg（最大值-最小值），地衣中 3470±571 至 648±40μgkg，苔藓中 3052±483 至 750±127μgkg。所有生物监测器在暴露的前 3 周后表现出最高的 Hg 积累。Hg 浓度随时间增加，在实验过程中持续积累。生物监测器对 GEM 浓度和植物标本馆展厅的不同气候条件（温度和湿度）表现出不同的 Hg 积累趋势。树皮严格反映了气态 Hg 污染，而地衣和苔藓的积累也受到室内环境气候条件的影响。与 PM 结合的 Hg 似乎对生物监测器的最终吸收贡献可以忽略不计。
