Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu... more Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu ents as well as the chem i cal indus try. Up to 24 000 ton of wood preservative, chlo ro phe nol known as Ky-5, was man ufac tured in the upper reaches of the river, an unknown amount of which was dis charged into the river between 1940 and 1984. Poly chlo ri nated dibenzo-p-di ox ins and dib enzofu rans (PCDD/Fs) occurred as impu ri ties in the final Ky-5 prod uct. The PCDD/F con cen tra tions and bur den in the river sed i ments were stud ied and the trans port of PCDD/Fs from con tam i nated sites down stream and into the Gulf of Fin land in the Bal tic Sea was esti mated. More than 190 sed i ment cores were sam pled to esti mate the vol ume of con tam i nated sed i ments and the total PCDD/F bur den. The trans port of PCDD/Fs was esti mated using sed i ment traps placed at sev eral sites. The sur vey revealed that sed i ments in the river were heav ily polluted by PCDD/Fs, the main toxic con ge ner being 1,2,3,4,6,7,8-hep ta chlorodibenzofu ran, a major con tam inant in the Ky-5 prod uct. The mean total con cen tra tion at the most pol luted river site down stream from the main source was 42 000 lg kg ¡1 d.w. (106 lg I-TEQ kg ¡1 ). The ele vated con cen tra tions in the coastal region and the pres ent esti mated trans port from the River Ky mij oki con firm ear lier assess ments that the river is a major source of PCDD/F for the Gulf of Fin land.
International Journal of Medical Informatics, 2009
Longevity Survival analysis a b s t r a c t Evidence-based dentistry has shown that different res... more Longevity Survival analysis a b s t r a c t Evidence-based dentistry has shown that different restorative materials have different survival times. Our primary hypothesis is that this should be revealed from normal dental records by the use of data mining technique and a practice-based dentistry approach analysed in a scientifically sound way. Dental records from 1626 patients and altogether 19,892 restorations in three Finnish age cohorts were analysed. Survival curves (Kaplan-Meier) were drawn for each of the restorative materials. Median survival times for amalgam and resinbased composites were more than 15 years in older cohorts. More than 60% of silicate cement restorations were replaced within 5 years, and more than 50% of glass ionomers within 7 years. There was a significant reduction in the longevity of amalgams in the 1980 cohort. Data mining of digital oral heath documents would be a useful tool to analyse survival curves of new restorative materials in a practice-based manner in real-life conditions.
In: 24th International Symposium on Halogenated Environmental Organic Pollutantsand POPs. Septemb... more In: 24th International Symposium on Halogenated Environmental Organic Pollutantsand POPs. September 6-10, 2004. Berlin, Germany. Organohalogen Compounds 66: 1378-1385. 24th International Symposium on Halogenated Environmental Organic Pollutants and POPs. September 6-10, 2004. Berlin, Germany
AbstractÐWe examined the eects of catchment characteristics and riverine processes on the concent... more AbstractÐWe examined the eects of catchment characteristics and riverine processes on the concentrations of nutrients and total suspended solids (TSS) using data from the outlets of 12 tributaries (9±139 km 2 ) and 22 main channel sites of a river draining an intensely cropped area of 1088 km 2 in SW Finland. For the tributaries, the¯ow-weighted mean concentrations of TSS and total phosphorus (TP), which both re¯ect erosion, were best explained by ®eld percentage and the mean slope of the ®elds of the catchment. The best model describing the concentration of dissolved reactive P (DRP) included ®eld percentage and catchment area. Total nitrogen (TN) and nitrate+nitrite-nitrogen (NO x -N) correlated only with ®eld percentage. Except for DRP, the regression models derived from the tributary data rather accurately predicted the concentrations in the main river channel. Our results suggest that, with regard to lakeless catchments of 10±1000 km 2 , the export of TP, TSS and N per unit area remains constant. Furthermore, although some P in eroded soil particles may be released into dissolved, algal-available form during the river transport, erosion control appears not to eciently reduce dissolved P. 7
Environmental Science and Pollution Research, 2009
Background, aim, and scope The paper describes the spatial contamination of the River Kymijoki, S... more Background, aim, and scope The paper describes the spatial contamination of the River Kymijoki, South-Eastern Finland, and the coastal region of the Gulf of Finland with PCDD/Fs and mercury. The findings of ecotoxicologial and human health studies are also reported, including environmental and human risk assessments. Sediments from the River Kymijoki, draining into the Gulf of Finland, have been heavily polluted by the pulp and paper industry and by chemical industries. A wood preservative, known as Ky-5, was manufactured in the upper reaches of the river between 1940 and 1984 causing severe pollution of river sediments with polychlorinated dibenzo-p-dioxins (PCDD) and diben- Environ Sci Pollut Res (2009) 16:95-105
The highest PCDD/Fs sedimentation were in the Kymijoki estuary with a known historic source. No s... more The highest PCDD/Fs sedimentation were in the Kymijoki estuary with a known historic source. No significant decrease over time was found in sedimentation in the estuary of Kymijoki. Sedimentation of PCDD/Fs was an order of magnitude higher in river estuaries than offshore. The short term sedimentation of PCDD/Fs in offshore reference stations was notably higher than the air deposition rates. g r a p h i c a l a b s t r a c t a b s t r a c t Sediment trap material was collected during May-December in the period 1996-2008 in three coastal areas and four open sea stations in the Finnish territory of the Baltic Sea. The highest sedimentation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) with a typical source-related congener profile from chlorophenol production dominated by highly chlorinated dibenzofurans was found close to a historical source in the Kymijoki estuary. This was an order of magnitude higher than in other river estuaries and two orders of magnitude higher than in the open sea stations. The sedimentation of polychlorinated biphenyls (PCBs) was also higher in river estuaries than in other areas. No significant decrease over a 12 year period of monitoring was found in concentration or in sedimentation in the Kymijoki estuary. In the western Gulf of Finland, the Archipelago Sea and the Gulf of Bothnia, the dominating congeners, calculated as toxic equivalent (TEQ) in sedimentation were 1, 2, 3, 7, 8-PeCDD and 2, 3, 4, 7, 8-PeCDF, often reported as the main congeners in deposition.
Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) ... more Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) in Baltic Sea sediments from Finland, Sweden and Denmark were merged with previously published Baltic Sea data. Regional distribution of concentration levels, differences in congener patterns, and temporal changes in sediment profiles were examined. One of the main objectives was to study if any major point sources for different PCDD/F congeners could be identified on a regional scale, based on sediment records. The survey confirmed the impact of chlorophenol production derived highly chlorinated PCDF-congeners on the total toxicity in sediments in the Gulf of Finland near the Kymijoki river estuary. Signatures of other point sources or combined point sources pertinent to specific industry branches or particular production processes (such as pulp bleaching, vinyl chloride production, thermal processes) may be discerned. However, the findings did not support any of the known point sources significantly influencing those congeners that are most abundant in Baltic herring and salmon. Instead, regional distributions in the Baltic Sea indicate that atmospheric deposition may act as a major source for those congeners and especially for 2,3,4,7,8-PeCDF. There were clear indications of declines in levels in sediment in some areas, but generally the levels of highly chlorinated PCDD/Fs on the northern coast of the Gulf of Finland were still high when compared with other areas of the Baltic Sea. Major areas with data gaps cover the south-eastern and eastern coastal regions of the Baltic Proper and the southern Gulf of Finland.
Sediments polluted with high concentrations of persistent organic pollutants, many of which are l... more Sediments polluted with high concentrations of persistent organic pollutants, many of which are ligands of the aryl hydrocarbon receptor (AhR), are currently of concern around the industrialized world. Bioassays that can detect the presence of AhR ligands in environmental samples offer a relatively rapid and costeffective means of prioritizing samples before more elaborate, laborious, and costly chemical analyses are applied. This paper presents a new bioluminescent yeast assay based on transcriptional activation of AhR. Its applicability for determining AhR ligands in complex environmental samples was demonstrated by analyzing a set of sediment samples from the River Kymi, Finland. The results from the assay are shown to be consistent with those from both a chemical analysis and an H4IIE-luc bioassay. The yeast assay procedure is simple and can be performed within 1 day. The yeasts grow rapidly, are easy to handle, and do not require continuous cell culturing. Moreover, the robustness of the yeast allows the application of the test to crude extracts or even sediment suspensions. The yeast assay described in this paper can be useful in screening and prioritization of samples prior to chemical analysis. Moreover, the strain can be used in the construction of fibre-optic biosensors.
Climate change is projected to increase mean temperature of northern lakes by the end of the twen... more Climate change is projected to increase mean temperature of northern lakes by the end of the twenty-first century. To simulate this scenario, during 2004-2007 we imposed artificial mixing in Halsjärvi, a small, polyhumic, boreal lake in southern Finland, to increase the depth of the thermocline by *1.5 m. The aims of the experiment were to evaluate potential effects of climate change on biogeochemical cycles, especially of mercury, and on food web structure, productivity and biodiversity in dystrophic lake ecosystems. Following the initial depression of the thermocline in the experimental lake, the methyl mercury (MeHg) concentration in small European perch (Perca fluviatlis L.) decreased and remained lower throughout the study. In contrast, perch in a nearby reference lake exhibited increased MeHg during the same period. The d 15 N values of the muscle tissue of perch were similar in both lakes over the study period, suggesting that the trophic position of perch remained unchanged. However, d 13 C values of perch became clearly more negative in Halsjärvi, probably due to the greater mixing of the water column that resulted in changes in the carbon sources for the food web. A marked decrease of epilimnetic MeHg concentrations recorded during the experiment was considered to be the main reason for the decreased MeHg concentrations in perch. The results suggest that oxygen-related changes induced by climate change will be more important than direct temperature changes for MeHg accumulation in fish in small humic lakes with persistent oxygen deficiency in the hypolimnion.
Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu... more Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu ents as well as the chem i cal indus try. Up to 24 000 ton of wood preservative, chlo ro phe nol known as Ky-5, was man ufac tured in the upper reaches of the river, an unknown amount of which was dis charged into the river between 1940 and 1984. Poly chlo ri nated dibenzo-p-di ox ins and dib enzofu rans (PCDD/Fs) occurred as impu ri ties in the final Ky-5 prod uct. The PCDD/F con cen tra tions and bur den in the river sed i ments were stud ied and the trans port of PCDD/Fs from con tam i nated sites down stream and into the Gulf of Fin land in the Bal tic Sea was esti mated. More than 190 sed i ment cores were sam pled to esti mate the vol ume of con tam i nated sed i ments and the total PCDD/F bur den. The trans port of PCDD/Fs was esti mated using sed i ment traps placed at sev eral sites. The sur vey revealed that sed i ments in the river were heav ily polluted by PCDD/Fs, the main toxic con ge ner being 1,2,3,4,6,7,8-hep ta chlorodibenzofu ran, a major con tam inant in the Ky-5 prod uct. The mean total con cen tra tion at the most pol luted river site down stream from the main source was 42 000 lg kg ¡1 d.w. (106 lg I-TEQ kg ¡1 ). The ele vated con cen tra tions in the coastal region and the pres ent esti mated trans port from the River Ky mij oki con firm ear lier assess ments that the river is a major source of PCDD/F for the Gulf of Fin land.
Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu... more Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu ents as well as the chem i cal indus try. Up to 24 000 ton of wood preservative, chlo ro phe nol known as Ky-5, was man ufac tured in the upper reaches of the river, an unknown amount of which was dis charged into the river between 1940 and 1984. Poly chlo ri nated dibenzo-p-di ox ins and dib enzofu rans (PCDD/Fs) occurred as impu ri ties in the final Ky-5 prod uct. The PCDD/F con cen tra tions and bur den in the river sed i ments were stud ied and the trans port of PCDD/Fs from con tam i nated sites down stream and into the Gulf of Fin land in the Bal tic Sea was esti mated. More than 190 sed i ment cores were sam pled to esti mate the vol ume of con tam i nated sed i ments and the total PCDD/F bur den. The trans port of PCDD/Fs was esti mated using sed i ment traps placed at sev eral sites. The sur vey revealed that sed i ments in the river were heav ily polluted by PCDD/Fs, the main toxic con ge ner being 1,2,3,4,6,7,8-hep ta chlorodibenzofu ran, a major con tam inant in the Ky-5 prod uct. The mean total con cen tra tion at the most pol luted river site down stream from the main source was 42 000 lg kg ¡1 d.w. (106 lg I-TEQ kg ¡1 ). The ele vated con cen tra tions in the coastal region and the pres ent esti mated trans port from the River Ky mij oki con firm ear lier assess ments that the river is a major source of PCDD/F for the Gulf of Fin land.
International Journal of Medical Informatics, 2009
Longevity Survival analysis a b s t r a c t Evidence-based dentistry has shown that different res... more Longevity Survival analysis a b s t r a c t Evidence-based dentistry has shown that different restorative materials have different survival times. Our primary hypothesis is that this should be revealed from normal dental records by the use of data mining technique and a practice-based dentistry approach analysed in a scientifically sound way. Dental records from 1626 patients and altogether 19,892 restorations in three Finnish age cohorts were analysed. Survival curves (Kaplan-Meier) were drawn for each of the restorative materials. Median survival times for amalgam and resinbased composites were more than 15 years in older cohorts. More than 60% of silicate cement restorations were replaced within 5 years, and more than 50% of glass ionomers within 7 years. There was a significant reduction in the longevity of amalgams in the 1980 cohort. Data mining of digital oral heath documents would be a useful tool to analyse survival curves of new restorative materials in a practice-based manner in real-life conditions.
In: 24th International Symposium on Halogenated Environmental Organic Pollutantsand POPs. Septemb... more In: 24th International Symposium on Halogenated Environmental Organic Pollutantsand POPs. September 6-10, 2004. Berlin, Germany. Organohalogen Compounds 66: 1378-1385. 24th International Symposium on Halogenated Environmental Organic Pollutants and POPs. September 6-10, 2004. Berlin, Germany
AbstractÐWe examined the eects of catchment characteristics and riverine processes on the concent... more AbstractÐWe examined the eects of catchment characteristics and riverine processes on the concentrations of nutrients and total suspended solids (TSS) using data from the outlets of 12 tributaries (9±139 km 2 ) and 22 main channel sites of a river draining an intensely cropped area of 1088 km 2 in SW Finland. For the tributaries, the¯ow-weighted mean concentrations of TSS and total phosphorus (TP), which both re¯ect erosion, were best explained by ®eld percentage and the mean slope of the ®elds of the catchment. The best model describing the concentration of dissolved reactive P (DRP) included ®eld percentage and catchment area. Total nitrogen (TN) and nitrate+nitrite-nitrogen (NO x -N) correlated only with ®eld percentage. Except for DRP, the regression models derived from the tributary data rather accurately predicted the concentrations in the main river channel. Our results suggest that, with regard to lakeless catchments of 10±1000 km 2 , the export of TP, TSS and N per unit area remains constant. Furthermore, although some P in eroded soil particles may be released into dissolved, algal-available form during the river transport, erosion control appears not to eciently reduce dissolved P. 7
Environmental Science and Pollution Research, 2009
Background, aim, and scope The paper describes the spatial contamination of the River Kymijoki, S... more Background, aim, and scope The paper describes the spatial contamination of the River Kymijoki, South-Eastern Finland, and the coastal region of the Gulf of Finland with PCDD/Fs and mercury. The findings of ecotoxicologial and human health studies are also reported, including environmental and human risk assessments. Sediments from the River Kymijoki, draining into the Gulf of Finland, have been heavily polluted by the pulp and paper industry and by chemical industries. A wood preservative, known as Ky-5, was manufactured in the upper reaches of the river between 1940 and 1984 causing severe pollution of river sediments with polychlorinated dibenzo-p-dioxins (PCDD) and diben- Environ Sci Pollut Res (2009) 16:95-105
The highest PCDD/Fs sedimentation were in the Kymijoki estuary with a known historic source. No s... more The highest PCDD/Fs sedimentation were in the Kymijoki estuary with a known historic source. No significant decrease over time was found in sedimentation in the estuary of Kymijoki. Sedimentation of PCDD/Fs was an order of magnitude higher in river estuaries than offshore. The short term sedimentation of PCDD/Fs in offshore reference stations was notably higher than the air deposition rates. g r a p h i c a l a b s t r a c t a b s t r a c t Sediment trap material was collected during May-December in the period 1996-2008 in three coastal areas and four open sea stations in the Finnish territory of the Baltic Sea. The highest sedimentation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) with a typical source-related congener profile from chlorophenol production dominated by highly chlorinated dibenzofurans was found close to a historical source in the Kymijoki estuary. This was an order of magnitude higher than in other river estuaries and two orders of magnitude higher than in the open sea stations. The sedimentation of polychlorinated biphenyls (PCBs) was also higher in river estuaries than in other areas. No significant decrease over a 12 year period of monitoring was found in concentration or in sedimentation in the Kymijoki estuary. In the western Gulf of Finland, the Archipelago Sea and the Gulf of Bothnia, the dominating congeners, calculated as toxic equivalent (TEQ) in sedimentation were 1, 2, 3, 7, 8-PeCDD and 2, 3, 4, 7, 8-PeCDF, often reported as the main congeners in deposition.
Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) ... more Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) in Baltic Sea sediments from Finland, Sweden and Denmark were merged with previously published Baltic Sea data. Regional distribution of concentration levels, differences in congener patterns, and temporal changes in sediment profiles were examined. One of the main objectives was to study if any major point sources for different PCDD/F congeners could be identified on a regional scale, based on sediment records. The survey confirmed the impact of chlorophenol production derived highly chlorinated PCDF-congeners on the total toxicity in sediments in the Gulf of Finland near the Kymijoki river estuary. Signatures of other point sources or combined point sources pertinent to specific industry branches or particular production processes (such as pulp bleaching, vinyl chloride production, thermal processes) may be discerned. However, the findings did not support any of the known point sources significantly influencing those congeners that are most abundant in Baltic herring and salmon. Instead, regional distributions in the Baltic Sea indicate that atmospheric deposition may act as a major source for those congeners and especially for 2,3,4,7,8-PeCDF. There were clear indications of declines in levels in sediment in some areas, but generally the levels of highly chlorinated PCDD/Fs on the northern coast of the Gulf of Finland were still high when compared with other areas of the Baltic Sea. Major areas with data gaps cover the south-eastern and eastern coastal regions of the Baltic Proper and the southern Gulf of Finland.
Sediments polluted with high concentrations of persistent organic pollutants, many of which are l... more Sediments polluted with high concentrations of persistent organic pollutants, many of which are ligands of the aryl hydrocarbon receptor (AhR), are currently of concern around the industrialized world. Bioassays that can detect the presence of AhR ligands in environmental samples offer a relatively rapid and costeffective means of prioritizing samples before more elaborate, laborious, and costly chemical analyses are applied. This paper presents a new bioluminescent yeast assay based on transcriptional activation of AhR. Its applicability for determining AhR ligands in complex environmental samples was demonstrated by analyzing a set of sediment samples from the River Kymi, Finland. The results from the assay are shown to be consistent with those from both a chemical analysis and an H4IIE-luc bioassay. The yeast assay procedure is simple and can be performed within 1 day. The yeasts grow rapidly, are easy to handle, and do not require continuous cell culturing. Moreover, the robustness of the yeast allows the application of the test to crude extracts or even sediment suspensions. The yeast assay described in this paper can be useful in screening and prioritization of samples prior to chemical analysis. Moreover, the strain can be used in the construction of fibre-optic biosensors.
Climate change is projected to increase mean temperature of northern lakes by the end of the twen... more Climate change is projected to increase mean temperature of northern lakes by the end of the twenty-first century. To simulate this scenario, during 2004-2007 we imposed artificial mixing in Halsjärvi, a small, polyhumic, boreal lake in southern Finland, to increase the depth of the thermocline by *1.5 m. The aims of the experiment were to evaluate potential effects of climate change on biogeochemical cycles, especially of mercury, and on food web structure, productivity and biodiversity in dystrophic lake ecosystems. Following the initial depression of the thermocline in the experimental lake, the methyl mercury (MeHg) concentration in small European perch (Perca fluviatlis L.) decreased and remained lower throughout the study. In contrast, perch in a nearby reference lake exhibited increased MeHg during the same period. The d 15 N values of the muscle tissue of perch were similar in both lakes over the study period, suggesting that the trophic position of perch remained unchanged. However, d 13 C values of perch became clearly more negative in Halsjärvi, probably due to the greater mixing of the water column that resulted in changes in the carbon sources for the food web. A marked decrease of epilimnetic MeHg concentrations recorded during the experiment was considered to be the main reason for the decreased MeHg concentrations in perch. The results suggest that oxygen-related changes induced by climate change will be more important than direct temperature changes for MeHg accumulation in fish in small humic lakes with persistent oxygen deficiency in the hypolimnion.
Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu... more Ky mij oki, the fourth larg est river in Fin land, has been heav ily pol luted by pulp mill efflu ents as well as the chem i cal indus try. Up to 24 000 ton of wood preservative, chlo ro phe nol known as Ky-5, was man ufac tured in the upper reaches of the river, an unknown amount of which was dis charged into the river between 1940 and 1984. Poly chlo ri nated dibenzo-p-di ox ins and dib enzofu rans (PCDD/Fs) occurred as impu ri ties in the final Ky-5 prod uct. The PCDD/F con cen tra tions and bur den in the river sed i ments were stud ied and the trans port of PCDD/Fs from con tam i nated sites down stream and into the Gulf of Fin land in the Bal tic Sea was esti mated. More than 190 sed i ment cores were sam pled to esti mate the vol ume of con tam i nated sed i ments and the total PCDD/F bur den. The trans port of PCDD/Fs was esti mated using sed i ment traps placed at sev eral sites. The sur vey revealed that sed i ments in the river were heav ily polluted by PCDD/Fs, the main toxic con ge ner being 1,2,3,4,6,7,8-hep ta chlorodibenzofu ran, a major con tam inant in the Ky-5 prod uct. The mean total con cen tra tion at the most pol luted river site down stream from the main source was 42 000 lg kg ¡1 d.w. (106 lg I-TEQ kg ¡1 ). The ele vated con cen tra tions in the coastal region and the pres ent esti mated trans port from the River Ky mij oki con firm ear lier assess ments that the river is a major source of PCDD/F for the Gulf of Fin land.
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