CE3C-Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Bloco C2, Piso 5, 1749-016 Lisboa, Portugal; TECNATOX Group, Chemical Engineering Department, Universitat Rovira i Virgili, C/ Països Catalans, n° 26, 43007 Tarragona, Spain.
CE3C-Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Bloco C2, Piso 5, 1749-016 Lisboa, Portugal; Centre for Natural Resources and the Environment, Instituto Superior Técnico, Universidade de Lisboa (CERENA-IST-UL), Portugal.
Sci Total Environ. 2015 Mar 1;508:95-100. doi: 10.1016/j.scitotenv.2014.11.065. Epub 2014 Nov 29.
Lichens are one of the most useful environmental biomonitors, due to their ability to clearly reflect atmospheric deposition of pollutants. Dioxin and furan (PCDD/F) emissions have been reported to be decreasing in North European countries as a consequence of European regulations. This reduction has been perceptible across several environmental matrices, but it hasn't yet been shown in lichens as typical biomonitors of atmospheric pollution. In this work we compared concentrations of PCDD/Fs in two lichen species collected in a Mediterranean area with mixed land-uses, encompassing urban, industrial and natural areas, in 2009 and 2011 with the ones obtained in the same species collected in the same region in 2000. We found that PCDD/F concentrations in both lichen species have decreased approximately 70% since 2000 whereas industrial emissions have only decreased 25% for the same period. This substantial greater reduction observed in lichens may be due to several causes; after excluding fires as a possible explanation, we point out that possible causes could not only be the overall decrease in industrial emissions but also other causes such as traffic reduction and/or increase efficiency in the use of fuels. Capsule: PCDD/F concentrations in lichens have decreased 70% over the last decade, whereas industrial emissions have only decreased 25%.
地衣是最有用的环境生物监测器之一，因为它们能够清晰反映大气中污染物的沉积情况。据报道，随着欧洲法规的实施，北欧国家二恶英和呋喃（PCDD/F）的排放量有所减少。这种减少在多种环境基质中都很明显，但在作为大气污染典型生物监测器的地衣中尚未体现出来。在这项工作中，我们比较了在 2009 年和 2011 年收集的两种混合土地利用的地中海地区地衣中的 PCDD/F 浓度，这些土地利用包括城市、工业和自然地区，以及在 2000 年同一地区收集的同一物种中的 PCDD/F 浓度。我们发现，自 2000 年以来，两种地衣物种中的 PCDD/F 浓度都下降了约 70%，而同期工业排放量仅下降了 25%。与工业排放相比，地衣中观察到的这种明显更大的减少可能有几个原因；在排除火灾作为可能的解释后，我们指出，可能的原因不仅是工业排放的总体减少，还有其他原因，如交通减少和/或燃料使用效率提高。结论：在过去十年中，地衣中的 PCDD/F 浓度下降了 70%，而工业排放量仅下降了 25%。
