Isotopic composition of sulphates from meteoric precipitation as an indicator of pollutant origin in Wrocław (SW Poland)†

†Revised version of a paper presented at the 9th. Symposium of the European Society for Isotope Research (ESIR), 23 to 28 June 2007, Cluj-Napoca, Romania.

Abstract

This paper describes the results of isotopic analyses of (i) hydrogen and oxygen in water (δ D and δ¹⁸O) and (ii) sulphur and oxygen in sulphates (δ³⁴S_sulphate and δ¹⁸O_sulphate) from atmospheric precipitation collected within a one-year period between 25 May 2004 and 25 May 2005 in Wrocław (SW Poland). The resulting equation of Local Meteoric Water Line for Wrocław is δ D=6.373×δ¹⁸O−0.047, (r ²=0.97, n=32). The δ³⁴S_sulphate varies from 1.1 to 4.2‰ (with an average of 2.5‰), δ¹⁸O_sulphate varies from 9.0 to 16.7‰ (with an average of 13.8‰) and δ¹⁸O varies from−0.8 to−16.3‰ (with an average of−8.2‰). The above results indicate two main sources of sulphates in Wrocław precipitation: (i) low-temperature secondary sulphates forming in situ in Wrocław from the atmospheric SO₂ as well as precipitation water (heterogeneous and homogeneous pathways oxidation) and (ii) high-temperature primary sulphates forming in rapid high-temperature hydratation of SO in an immediate proximity of industrial chimneys. We hypothesise that the secondary low-temperature type of sulphates is probably formed from the local sulphur and oxygen reservoirs, whereas the primary high-temperature type is allochthonous and it is probably transported from industrial areas located outside of Wrocław.

†Revised version of a paper presented at the 9th. Symposium of the European Society for Isotope Research (ESIR), 23 to 28 June 2007, Cluj-Napoca, Romania.

Keywords:

• atmosphere
• oxygen-18
• pollutants
• precipitation
• sulphates
• sulphur-34
• Wrocław

Acknowledgements

The meteorological data were obtained from the Meteorological Observatory of Wrocław (Section for Meteorology and Climatology, University of Wrocław). Great thanks are due to Wojciech Drzewicki for his substantial help in laboratory works, Dušan Golobočanin for statistical remarks and Prof. Stanisław Hałas for help in measurements of sulphur isotopic ratios. Great thanks are due to Dominika Lewicka-Szczebak for language correction and scientific consultancy. The manuscript has benefited a lot from the critical comments of two anonymous reviewers. The study was supported by the Polish Ministry of Education and Science, grant No. 3T09D08628 and University of Wrocław grants No. 1017/S/ING/05-IX, 2022/W/ING/05-49, 2022/W/ING/05-12.

Notes

†Revised version of a paper presented at the 9th. Symposium of the European Society for Isotope Research (ESIR), 23 to 28 June 2007, Cluj-Napoca, Romania.