Biomonitoring of airborne microplastics and microrubbers in Shiraz, Iran, using lichens and moss

Khodabakhshloo N., Abbasi S., Oleszczuk P. & Turner A.
Environmental Geochemistry and Health
46: 244 [14 p.]
Highlights: Microplastics (MPs) and microrubbers (MRs) determined in lichens and mosses around Shiraz. In lichens, MPs mainly thin fibres up to 1 MP g−1; MRs were 0.1 MP g−1. In mosses, abundances were similar but with a greater fraction of larger, non-fibrous particles. Larger MPs and MRs decreased in abundance with distnce and elevation from Shiraz. Around Shiraz, the common moss, Grimmia critina, would be the most suitable biomonitor. Lichens and mosses have been employed as biomonitors of atmospheric particulate pollutants, like metals and industrial solids, for many decades. Here, we evaluated the potential of nine species of crustose and foliose lichens and a widely distributed moss (Grimmia critina) to act as biomonitors of airborne microplastics (MPs) and microrubbers (MRs). About 200 lichens and 40 mosses were sampled across different altitudinal transects in the vicinity of Shiraz City, southwest Iran, and MPs and MRs were quantified and characterised after sample peroxidation. In most species of lichen, MP and MR abundance overall was  1 g−1 and  0.1 g−1, respectively, and the majority of plastics were fibres of  10 µm in diameter and  1000 µm) and non-fibrous particles among the MPs. In both lichens and moss, there was a greater number of larger MPs and MRs at locations closest to and at the same elevation as Shiraz than at more distant and elevated locations, suggesting an inverse relationship between particle size and distance travelled. Among the lichens, members of the genus Acarospora, with their areolated form, appeared to act as the most suitable biomonitors for MPs and MRs. Overall, however, the wide distribution of the moss, G. crinita, and its ability to intercept and accumulate a broader range of sizes and shapes of MPs and MRs make this species a better choice, at least in the type of environment studied. Keywords: Bryophyte · Fibres · Particulate · Grimmia · Acarospora · Contaminants.
Monday, 24 June 2024 10:06