After the phasing out of leaded gasoline, Pb emissions to the atmosphere dramatically decreased, and other sources became more significant. The contribution of unleaded gasoline has not been sufficiently recognized; therefore, we evaluated the impact of Pb from unleaded gasoline in a relatively pristine area in Subarctic NE Norway. The influence of different endmembers (Ni slag and concentrate from the Nikel smelter in Russia, PM10filters, and traffic) on the overall Pb emissions was determined using various environmental samples (snow, lichens, and topsoils) and Pb isotope tracing. We found a strong relationship between Pb in snow and the Ni smelter. However, lichen samples and most of the topsoils were contaminated by Pb originating from the current use of unleaded gasoline originating from Russia. Historical leaded and recent unleaded gasoline are fully distinguishable using Pb isotopes, as unleaded gasoline is characterized by a low radiogenic composition (206Pb/207Pb = 1.098 and208Pb/206Pb = 2.060) and remains an unneglectable source of Pb in the region.
- MeSH
- atmosféra chemie MeSH
- benzin analýza MeSH
- izotopy analýza MeSH
- látky znečišťující životní prostředí analýza MeSH
- lišejníky chemie MeSH
- monitorování životního prostředí * MeSH
- olovo analýza MeSH
- sníh chemie MeSH
- výfukové emise vozidel analýza MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Norsko MeSH
- Rusko MeSH
The use of Ni and Cu isotopes for tracing contamination sources in the environment remains a challenging task due to the limited information about the influence of various biogeochemical processes influencing stable isotope fractionation. This work focuses on a relatively simple system in north-east Norway with two possible endmembers (smelter-bedrock) and various environmental samples (snow, soil, lichens, PM10). In general, the whole area is enriched in heavy Ni and Cu isotopes highlighting the impact of the smelting activity. However, the environmental samples exhibit a large range of δ(60)Ni (-0.01 ± 0.03‰ to 1.71 ± 0.02‰) and δ(65)Cu (-0.06 ± 0.06‰ to -3.94 ± 0.3‰) values which exceeds the range of δ(60)Ni and δ(65)Cu values determined in the smelter, i.e. in feeding material and slag (δ(60)Ni from 0.56 ± 0.06‰ to 1.00 ± 0.06‰ and δ(65)Cu from -1.67 ± 0.04‰ to -1.68 ± 0.15‰). The shift toward heavier Ni and Cu δ values was the most significant in organic rich topsoil samples in the case of Ni (δ(60)Ni up to 1.71 ± 0.02‰) and in lichens and snow in the case of Cu (δ(65)Cu up to -0.06 ± 0.06‰ and -0.24 ± 0.04‰, respectively). These data suggest an important biological and biochemical fractionation (microorganisms and/or metal uptake by higher plants, organo-complexation etc.) of Ni and Cu isotopes, which should be quantified separately for each process and taken into account when using the stable isotopes for tracing contamination in the environment.
