title: Post 17th-century changes of European PAH emissions recorded in high-altitude Alpine snow and ice.
abstract: The occurrence of organic pollutants in European Alpine snow/ice has been reconstructed over the past three centuries using a new online extraction method for polycyclic aromatic hydrocarbons (PAH) followed by liquid chromatographic determination. The meltwater flow from a continuous ice core melting system was split into two aliquots, with one aliquot directed to an inductively coupled plasma quadrupole mass spectrometer for continuous trace elements determinations and the second introduced into a solid phase C18 (SPE) cartridge for semicontinuous PAH extraction. The depth resolution for PAH extractions ranged from 40 to 70 cm, and corresponds to 0.7-5 years per sample. The concentrations of 11 PAH were determined in dated snow/ice samples to reconstruct the atmospheric concentration of these compounds in Europe for the last 300 years. The PAH pattern is dominated by phenanthrene (Phe), fluoranthene (Fla), and pyrene (Pyr), which represent 60-80% of the total PAH mass. Before 1875 the sum of PAH concentration (SigmaPAH) was very low with total mean concentrations less than 2 ng/kg and 0.08 ng/kg for the heavier compounds (SigmaPAH*, more than four aromatic rings). During the first phase of the industrial revolution (1770-1830) the PAH deposition showed a weak increase which became much greater from the start of the second phase of the industrial revolution at the end of 19th Century. In the 1920s, economic recession in Europe decreased PAH emissions until the 1930s when they increased again and reached a maximum concentration of 32 ng/kg from 1945 to 1955. From 1955 to 1975 the PAH concentrations decreased significantly, reflecting improvements in emission controls especially from major point sources, while from 1975 to 2003 they rose to levels equivalent to those in 1910. The Fla/(Fla+Pyr) ratio is often used for source assignment and here indicates an increase in the relative contribution of gasoline and diesel combustion with respect to coal and wood burning from 1860 to the 1980s. This trend was reversed during the last two decades.
authors.affiliation: Department of Environmental Sciences, University Ca' Foscari of Venice, Dorsoduro 2137, 30123 Venice, Italy.
authors.forename: Jacopo
authors.initials: J
authors.lastname: Gabrieli
authors.forename: Paul
authors.initials: P
authors.lastname: Vallelonga
authors.forename: Giulio
authors.initials: G
authors.lastname: Cozzi
authors.forename: Paolo
authors.initials: P
authors.lastname: Gabrielli
authors.forename: Andrea
authors.initials: A
authors.lastname: Gambaro
authors.forename: Michael
authors.initials: M
authors.lastname: Sigl
authors.forename: Fabio
authors.initials: F
authors.lastname: Decet
authors.forename: Margit
authors.initials: M
authors.lastname: Schwikowski
authors.forename: Heinz
authors.initials: H
authors.lastname: Gäggeler
authors.forename: Claude
authors.initials: C
authors.lastname: Boutron
authors.forename: Paolo
authors.initials: P
authors.lastname: Cescon
authors.forename: Carlo
authors.initials: C
authors.lastname: Barbante
mesh_terms: D000393:Air Pollutants / Q000032:analysis; D000531:Altitude; D002845:Chromatography / Q000379:methods; D002853:Chromatography, Liquid / Q000379:methods; D004784:Environmental Monitoring / Q000379:methods; D005060:Europe; D007053:Ice / Q000032:analysis*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D015203:Reproducibility of Results; D012914:Snow; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical
chemical_list: D000393:Air Pollutants; D007053:Ice; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D014867:Water