Spatial variability of POPs in European background air

Abstract

Passive air samplers (PAS) were deployed at 86 European background sites during summer 2006 in order (i) to gain further insight into spatial patterns of persistent organic pollutants (POPs) in European background air and, (ii) to evaluate PAS as an alternative sampling technique under EMEP (Co-operative programme for monitoring and evaluation of the long-range transmissions of air pollutants in Europe). The samples were analyzed for selected PCBs, HCHs, DDTs, HCB, PAHs and chlordanes, and air concentrations were calculated on the basis of losses of performance reference compounds. Air concentrations of PCBs were generally lowest in more remote areas of northern Europe with elevated levels in more densely populated areas. <i>γ</i>-HCH was found at elevated levels in more central parts of Europe, whereas <i>α</i>-HCH, <i>β</i>-HCH and DDTs showed higher concentrations in the south-eastern part. There was no clear spatial pattern in the concentrations for PAHs, indicative of influence by local sources, rather than long range atmospheric transport (LRAT). HCB was evenly distributed across Europe, while the concentrations of chlordanes were typically low or non-detectable. A comparison of results obtained on the basis of PAS and active air sampling (AAS) illustrated that coordinated PAS campaigns have the potential serve as useful inter-comparison exercises within and across existing monitoring networks. The results also highlighted limitations of the current EMEP measurement network with respect to spatial coverage. We finally adopted an existing Lagrangian transport model (FLEXPART) as recently modified to incorporate key processes relevant for POPs to evaluate potential source regions affecting observed concentrations at selected sites. Using PCB-28 as an example, the model predicted concentrations which agreed within a factor of 3 with PAS measurements for all except 1 out of the 17 sites selected for this analysis

A comparison study of atmospheric polycyclic aromatic hydrocarbons in three Indian cities using PUF disk passive air samplers

“…The concentrations in Indian air were dominated by the 3e4-ring PAHs, following the order Phe (w32%) > Pyr (w15%) > Chr (w12%)> Flur (w11%)>Flu (w10%), while the proportions of the other PAHs were <7%. Compared with the congener profiles in cities (Liu et al, 2007;Bohlin et al, 2008) and background sites (Halse et al, 2011), the Indian air was characterized by a relatively high proportion of HMW PAHs. An enrichment of HMW PAHs in the air was also recorded at a rural site in Chennai (Masih et al, 2012).…”

Increasing and decreasing trends of the atmospheric deposition of organochlorine compounds in European remote areas during the last decade

“…The higher concentrations of OCs, especially PCBs, in east Europe are consistent with the high historical use and production of these compounds in central Europe and the former Czechoslovakia until 1984 (Taniyasu et al, 2003;Holoubek et al, 2007). Similar spatial distribution of PCBs and HCHs in remote European air samples was observed elsewhere (Halse et al, 2011), with higher concentrations in east Europe and lower in the Iberian Peninsula, which was attributed to the prevailing wind regimes from west to east. Nevertheless, these authors also found low levels of these compounds in the atmosphere over the British Isles, which is not observed in the present study.…”

“…In addition, higher Henry's law constant of α-HCH than γ - HCH would enhance the predominant deposition of γ over α-isomer which will lower the ratio in relation to what is present in the atmosphere. A dominant usage of lindane has been reported in the western part of Europe, while the technical HCH tended to dominate in east Europe (Halse et al, 2011). This geographical difference is not reflected in the atmospheric deposition patterns of this study, since the α/γ -HCH ratios were consistently lower in the eastern and central European sites, Gossenköllesee and Skalnaté, than in Lochnagar and Redòn, situated in western Europe (Table 2).…”

“…In fact, declines in PCB air concentrations as a consequence of the ban of these compounds have been reported (Holoubek et al, 2007;Halse et al, 2011;Schuster et al, 2010). However, in remote areas such as Svalbard (Norway) and the Canadian Arctic increases of PCB air concentrations have been observed, be-ing attributed to the remobilization of these compounds from Arctic reservoirs like waters, soils and snow/ice as a result of sea-ice retreat and rising temperatures induced by climate change (Ma et al, 2011).…”

“…Conversely, positive correlations were found between total endosulfans and back-trajectories coming from the south (North Africa, Mediterranean Sea and/or Iberian Peninsula) in this site as well as in Lochnagar, which is consistent with the potential emission sources of this pesticide from areas of intensive agricultural activities. In addition, back-trajectories from central/east Europe corresponded to higher α/γ -HCH ratios in Gossenköllesee according with the prevalent use of technical HCH in eastern Europe (Halse et al, 2011) and the impact of air pollution transported from the east at this site (Kaiser, 2009). …”