title: New Insights from Zinc and Copper Isotopic Compositions into the Sources of Atmospheric Particulate Matter from Two Major European Cities.
abstract: This study reports spatial and temporal variability of Zn and Cu isotopes in atmospheric particulate matter (PM) collected in two major European cities with contrasting atmospheric pollution, Barcelona and London. We demonstrate that nontraditional stable isotopes identify source contributions of Zn and Cu and can play a major role in future air quality studies. In Barcelona, samples of fine PM were collected at street level at sites with variable traffic density. The isotopic signatures ranged between -0.13 ± 0.09 and -0.51 ± 0.05‰ for δ(66)ZnIRMM and between +0.04 ± 0.20 and +0.33 ± 0.15‰ for δ(65)CuAE633. Copper isotope signatures similar to those of Cu sulfides and Cu/Sb ratios within the range typically found in brake wear suggest that nonexhaust emissions from vehicles are dominant. Negative Zn isotopic signatures characteristic for gaseous emissions from smelting and combustion and large enrichments of Zn and Cd suggest contribution from metallurgical industries. In London, samples of coarse PM collected on the top of a building over 18 months display isotope signatures ranging between +0.03 ± 0.04 and +0.49 ± 0.02‰ for δ(66)ZnIRMM and between +0.37 ± 0.17 and +0.97 ± 0.21‰ for δ(65)CuAE633. Heavy Cu isotope signatures (up to +0.97 ± 0.21‰) and higher enrichments and Cu/Sb ratios during winter time indicate important contribution from fossil fuel combustion. The positive δ(66)ZnIRMM signatures are in good agreement with signatures characteristic for ore concentrates used for the production of tires and galvanized materials, suggesting nonexhaust emissions from vehicles as the main source of Zn pollution.
authors: Department of Earth Science and Engineering, Imperial College London , London, SW7 2AZ, United Kingdom.
authors: R Ochoa
authors: RO
authors: Gonzalez
authors: Imaging and Analysis Centre, Natural History Museum , London, SW7 5BD, United Kingdom.
authors: S
authors: S
authors: Strekopytov
authors: Institute of Environmental Assessment and Water Research , Barcelona, 08034, Spain.
authors: F
authors: F
authors: Amato
authors: Institute of Environmental Assessment and Water Research , Barcelona, 08034, Spain.
authors: X
authors: X
authors: Querol
authors: Institute of Environmental Assessment and Water Research , Barcelona, 08034, Spain.
authors: C
authors: C
authors: Reche
authors: Department of Earth Science and Engineering, Imperial College London , London, SW7 2AZ, United Kingdom.
authors: D
authors: D
authors: Weiss
mesh_terms: D000393:Air Pollutants; D002947:Cities; D003300:Copper; D004784:Environmental Monitoring; D052638:Particulate Matter; D015032:Zinc
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D003300:Copper; D015032:Zinc