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  1. DISSOLVED ORGANOCHLORINE AND PAH POLLUTION PROFILES IN LITHUANIAN AND SWEDISH WATERAudroneZaliauskiene, Ilona Jegorova, *Per-Anders BergqvistEnvironmental Engineering, Kaunas University of Technology, Kaunas, Lithuania*Environmental Chemistry, Umeå University, SE-901 87 Umeå, Sweden Di PCB Tri PCB Tetra PCB Penta PCB Hexa PCB Umeå Kaunas Introduction The purpose of this work was to carry out a single three week monitoring in Lithuanian and Swedish water using semipermeable membrane devices (SPMDs) in order to estimate and compare PCB, PAH and pesticide concentrations. The results show, that the Lithuanian rivers – Neris and Nemunas in general are more polluted than Swedish streams Tvärån and Djupbäcken even comparing with Umeå river the levels was elevated. When comparing the two Lithuanian rivers, we found that Nemunas contains higher concentrations than Neris. Neris and Nemunas surrounds the Kaunas city. The sampling sites were located downstream industrial areas and upstream urbanized areas. The Swedish streams were examined since no fish spawning was observed during the last years. Large part of these streams consist of storm water. Results and discussion PAHFrom graphs below we can see that PAH concentrations in the Swedish streams is rather small compared with the two investigated Lithuanian rivers. Nearly all PAH compounds analyzed was detected in Lithuanian rivers. Phenantrene showed the highest concentration – 7,7 ng/L. It was also found elevated concentrations of fluoranthene and pyrene –5,2 ng/L and 3,2 ng/L, respectively.In the Lithuanian rivers four rings PAH compounds dominates, and in Swedish streams dominated two and three ring compounds. PCBUsually concentration of PCBs decrease going from PCB #28 to PCB #180, but looking on the profile of concentrations in Neris and Nemunas we could see the dominating peaks for PCB #110 and PCB #118. Since the concentrations of PCB #28 was found to be relatively higher, it indicates that the pollution could be more recent. PCB congeneres were detected at higher concentrations in the Lithuanian rivers. In Swedish waters PCB congeners were detected onlyat Krokvagen and Millbridge (PCB #28, PCB #31, PCB #44, PCB #110), and these concentrations were close to detection limit. The highest concentrations in Lithuanian rivers were observed for PCB #28 – 0,43 ng/L, PCB #31 – 0,24 ng/L, PCB #110 – 0,33 ng/L. PAH concentrations in sampling places PCB concentrations in sampling places Materials and methods Semipermeable membrane devices (SPMDs) are passive samplers used for measuring the truly dissolved concentration of Persistent Organic Pollutant (POPs) in water. SPMD devices are new, versatile, non-destructive methods, without any advanced or costly equipment requirements. Semipermeable membranes filled with lipophilic solvent are possible to use for the evaluation of bioavailability of organic compounds. SPMD data can be used to study variation in organic pollutant concentrations in space and time. As an alternative high volume sampling, semipermeable membrane devices (SPMDs) in water, was performed during 21 days. 6 sampling places was choosen for investigation. Pesticides The pesticide concentrations in the samples displayed higher concentrations in the Lithuanian rivers. Only o,p-DDE (2,1 ng/L), -HCH (0,54 ng/L) and p,p-DDE (0,66 ng/L) at the Upstream sampling site was higher in the Swedish streams investigated. Before the sampling site Upstream agricultural land, forests and green houses were dominating and could be the reason of pesticides leaking to stream. The highest concentrations in Lithuanian rivers were of the DDT metabolite DDMu – 1,17 ng/L, o,p-DDE – 1,57 ng/L, p,p-DDD – 0,41 ng/L. Pollution comparisonIn the last graph a comparison between the large rivers in Lithuania and one large river in Sweden can be seenindicating that the concentration of sumPAH in Neris and Nemunas was also elevated compared to Umea river. Higher concentrations were also identified for sumDDT and sumPCB. The dissolved water concentrations of -HCH (purified HCH products which consist of at least 99% -isomers are marketed under the comercial name lindane.), hexa-CBz and sumCHL (chlordane, which consist of a mixture of more than 140 different components) were similar in all three river sites. The compounds were dialysed and then fractionated by gel permeation chromatography (GPC) technique followed by a silica column. PAHs, PCBs and pesticides were identified by gas chromatography and mass spectrometry (GC/MS). Interpretation of chromatograms and calculation of concentrations was done using sixteen internal standard (IS). SPMD technology are used to estimate ambient TWA (time weighted average) dissolved or vapour phase chemical concentrations. Pesticide concentrations at sampling sites Comparison of pollution in three rivers SIM In these figures we can see selected ion monitoring (SIM) chromatograms of five homolog groups of PCB from the Lithuanian river Nemunas at Kaunas and from sampling site Krokvägen in Tvärån stream in Umea, Sweden. For hexa-PCB (6 chlorine atoms in the chlorinated biphenyl) only limited amounts are dissolved in water. From the figures we can see, that Nemunas is more polluted than Tvärån stream. At sampling site Krokvägen an un-known compounds were detected at high concentration at 18,58 min reducing the visibility of di-PCB (2 chlorine atoms), but this homolog group is visible in Nemunas sample. Tri-PCB (3 chlorine atoms) pattern is not seen because of the large un-known peak with retention time 14,44 min. Tetra-PCB (4 chlorine atoms)was easily identitied in both places. Penta-PCB (5 chlorine atoms)was very close to detection limit in Sweden. SPMD sampling results in clean extract which is easy to evaluate, and the clean-up procedure can include only non-destructive steps. PCB from site Nemunas and from site Krokvägen • Conclusions: • Using SPMD it is possible to compare sampling sites in different placesand countries at the same time; • data from Integrated sampling of bioavaible compounds during 21 days was evaluated; • Lithuanian rivers were generally more polluted than Umeå streams and Umeå river. • PAH concentrations were ten times higher in Lithuanian rivers than in Umeåriver; • PCB concentrations were also higher in Lithuanian rivers. In Umeå streams PCB concentrations were equal; • the relatively higher concentration of low molecular weight PCB (as PCB#28) indicates a recent pollution in Lithuania; • DDT and lindane were detected before industrial area in Umeå (in upstream site). DDT concentrations were higher in Nemunas than in Neris; Acknowledgements – We wish to acknowledge Umea University, Socrates program and Kaunas University of Technology for financial support.

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