Polychlorinated Biphenyls (PCBs) at the JRC Ispra Site: Air Concentrations, Congener Patterns and Seasonal Variation-Results from the 1st Year of Atmospheric Monitoring of Persistent Organic Pollutants (POPs) at the Ispra EMEP Station

摘要

With the aim of gathering information on atmospheric POPs concentrations in one of the ¿monitoring holes¿ in Europe, a monitoring and research atmospheric site was set up at the JRC Ispra Site. Regular monitoring activities started on April 2005 and finished on March 2007 in this first stage. Air and precipitation samples were collected regularly throughout this period. First results obtained on PCBs ambient air concentrations (7 indicator PCBs: 28, 52, 101, 118, 153, 138 and 180) from the first year of monitoring (April 2005-2006) are presented in this report. In addition, congener patterns, air gas/particulate phase partition and seasonal variation are discussed. The range of ¿7 PCB total (gas + particulate phases) monthly averaged concentration during the sampling period varied from 76 ± 17 to 31 ± 5 pg m-3. Concentrations are within the range of those reported for rural, semi-rural or remote areas around the world. A seasonal variation of air concentrations was observed, with higher levels in summer months (higher average temperatures) and lower values in winter (lower average temperatures). In addition, indications of seasonal variation affecting congener patterns and the gas - particulate phase partition for the studied PCB were found. PCBs were in general predominant in the air gas phase, dominating therefore the contribution to the total airborne concentration, although the percentage in the gas phase decreases when increasing level of chlorination and during the low temperature season (winter months). A one year data set of PCB ambient air concentrations has been generated, constituting a useful dataset that now remains available for further use, such as inclusion in the EMEP network or for POPs fate modelling validation and future risk assessment of POPs in sub-alpine locations. More results for other target POPs are under processing and are expected to be reported soon.