Polychlorinated biphenyls (PCBs) in air and soil from a high-altitude pasture in the Italian Alps: evidence of CB-209 contamination.
This study analyses the seasonal trend of polychlorinated biphenyls (PCB) concentrations in air and soil from a high-altitude mountain pasture in the Italian Alps. PCB concentrations in soil were generally comparable to background levels and were lower than those previously measured in the same area. Only CB-209 unexpectedly showed high concentrations with respect to the other congeners. GC-MS-MS identification was very clear, rising a new problem of increasing PCB contamination concerning only CB-209, which is not present in commercial mixtures used in the past in Italy and Europe. Considering all of the congeners, seasonal PCB trends were observed both in air and in soil that were related to the temperature and precipitation measured specifically in the study area. Highly significant relationships were found between the temperature-normalised concentrations in soil and the precipitation amounts. A north/south enrichment factor was present only in soil with rapid early summer re-volatilisation kinetics from soil to air and autumn re-deposition events from air to soil. Fugacity ratio calculations confirmed these trends. Surface soils respond rapidly to meteorological variables, while subsurface soils respond much more slowly. Seasonal trends were different for the northern and southern sides of the mountain. A detailed picture of the interactions among temperature, precipitation, mountain aspects and soil features was obtained.
Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy. paolo.tremolada@unimi.it.
Paolo
P
Tremolada
Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy.
Niccolò
N
Guazzoni
Department of Environmental and Land Sciences (DISAT), University of Milan Bicocca, Piazza della Scienza 1, 20126, Milan, Italy.
Roberto
R
Comolli
Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy.
Marco
M
Parolini
Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy.
Serena
S
Lazzaro
Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy.
Andrea
A
Binelli
D000393:Air Pollutants / Q000032:analysis*; D000531:Altitude; D004784:Environmental Monitoring / Q000379:methods*; D007558:Italy; D007700:Kinetics; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D012621:Seasons; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D013696:Temperature; D014835:Volatilization
D000393:Air Pollutants; D012987:Soil; D012989:Soil Pollutants; D011078:Polychlorinated Biphenyls
Air contamination; Air-soil exchange; CB-209; PCBs; Seasonal trends; Soil contamination