Department of Civil and Environmental, Universidad de la Costa, Calle 58 #55-66, 080002, Barranquilla, Colombia; Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV/EHU, P.O. Box 644, 48080, Bilbao, Basque Country, Spain.
Department of Didactic of Mathematics, Experimental and Social Sciences, Faculty of Education and Sport, University of the Basque Country UPV/EHU, 01006, Vitoria-Gasteiz, Basque Country, Spain.
Chemosphere. 2022 Dec;309(Pt 2):136743. doi: 10.1016/j.chemosphere.2022.136743. Epub 2022 Oct 6.
Over the last decades, the concern about air pollution has increased significantly, especially in urban areas. Active sampling of air pollutants requires specific instrumentation not always available in all the laboratories. Passive sampling has a lower cost than active alternatives but still requires efforts to cover extensive areas. The use of biological systems as passive samplers might be a solution that provides information about air pollution to assist decision-makers in environmental health and urban planning. This study aims to employ subaerial biofilms (SABs) growing naturally on façades of historical and recent constructions as natural passive biomonitors of atmospheric heavy metals pollution. Concretely, SABs spontaneously growing on constructions located in a tropical climate, like the one of the city of Barranquilla (Colombia), have been used to develop the methodological approach here presented as an alternative to SABS grown under laboratory conditions. After a proper identification of the biocolonizers in the SAB through taxonomic and morphological observations, the study of the particulate matter accumulated on the SABs of five constructions was conducted under a multi-analytical approach based mainly on elemental imaging studies by micro Energy Dispersive X-ray fluorescence spectrometry (μ-EDXRF) and Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectrometry (SEM-EDS) techniques, trying to reduce the time needed and associated costs. This methodology allowed to discriminate metals that are part of the original structure of the SABs, from those coming from the anthropogenic emissions. The whole methodology applied assisted the identification of the main metallic particles that could be associated with nearby anthropogenic sources of emission such as Zn, Fe, Mn, Ni and Ti by SEM-EDS and by μ-EDXRF Ba, Sb, Sn, Cl and Br apart others; revealing that it could be used as a good alternative for a rapid screening of the atmospheric heavy metals pollution.
在过去的几十年里，人们对空气污染的担忧显著增加，尤其是在城市地区。空气污染物的主动采样需要特定的仪器，而这些仪器并非在所有实验室都能获得。被动采样的成本低于主动采样，但仍需要努力覆盖广泛的区域。利用生物系统作为被动采样器可能是一种解决方案，可以提供有关空气污染的信息，以帮助决策者在环境健康和城市规划方面做出决策。本研究旨在利用自然生长在历史和现代建筑外墙上的气生生物膜（SABs）作为大气重金属污染的天然被动生物监测器。具体来说，我们使用了在热带气候（如哥伦比亚巴兰基亚市）中自然生长在建筑物上的 SABs，来开发这里提出的方法，作为在实验室条件下生长的 SABs 的替代方法。在通过分类学和形态学观察对 SAB 中的生物殖民者进行适当识别后，我们对五座建筑物的 SAB 上积累的颗粒物进行了多分析研究，主要基于微能量色散 X 射线荧光光谱（μ-EDXRF）和扫描电子显微镜结合能量色散 X 射线光谱（SEM-EDS）技术的元素成像研究，试图减少所需的时间和相关成本。该方法能够区分作为 SAB 原始结构一部分的金属，以及来自人为排放的金属。应用的整个方法有助于识别可能与附近人为排放源相关的主要金属颗粒，如 SEM-EDS 和 μ-EDXRF 中的 Zn、Fe、Mn、Ni 和 Ti 以及 Ba、Sb、Sn、Cl 和 Br 等，这表明它可以作为快速筛选大气重金属污染的良好替代方法。
