Airborne Pb, Si, Zn and Pb as tracers for atmospheric pollution in Helsinki metropolitan area.

This study analyzed 16070 daily and 608 weekly air filter samples from the Helsinki metropolitan area collected between 1962 and 2005. The aim was to use the Potential Source Contribution Function (PSCF) to determine potential sources of silicon (Si), zinc (Zn), lead (Pb), and radioactive isotope Pb. The main sources for Si and Pb were industrial activities, particularly mining, metal industry, and traffic.

Cs and isotopic ratios of Pu and U in lichens and mosses from Russian Arctic areas.

Knowledge of past anthropogenic sources of radionuclide contamination in Russian Arctic areas is important to assess the radioecological situation of these less-studied regions. Therefore, we investigated the sources of radionuclide contamination in Russian Arctic in the 1990s. Lichen and moss samples were collected from 1993 to 1996 in Kola Peninsula, Franz Josef Land, and few other locations.

Evaluation of Cs, Xe and H activity concentrations monitored in the Arctic atmosphere.

This paper provides a brief introduction to the Arctic atmospheric radioactivity monitoring network. A decade of monitoring results have shown the Cs background levels in Arctic air range from 0.05 to 1.

Air radioactivity in Marambio Base: The peculiar character of Antarctic Peninsula.

The Antarctic region is considered to be the least contaminated in the world due to its specific location and separation of this area as well as low activity of humans (Hashimoto et al., 1988). Additionally, in accordance with the provision of the Antarctic Treaty System (Antarctic Treaty Secretariat, 2020) it is prohibited to conduct any actions with nuclear materials in this area.

Transfer of Natural Radionuclides in Terrestrial Food Chains-A Review of Investigations in Finland.

Transfer of natural radionuclides Pb, Po, U, and Th in subarctic food chains has been studied in Finland since the 1960s. The unique food chain lichen-reindeer-man related to Sami people in Finnish Lapland and other food chain options, from berries or mushrooms to man, have been explored and the activity concentrations of natural radionuclides in biological samples determined. The results from Finnish radioecological studies are summarized and differences in bioaccumulation between different radionuclides are discussed.

Separation method for Pu, Am and Sr in large air filter sample sets.

A sequential separation method for Pu, Am, and Sr was applied for unusually large sample sets of air filters. The sample sets were combined weekly air filters covering sampling time from three months to five years, while in original method, the analyzed air filters had sampling time of only 1-3 days, containing significantly less organic and inorganic matrix and natural radionuclides. The separation method is based on ashing and wet-ashing, followed by column separations with extraction chromatography and anion exchange.

Decreased carbon accumulation feedback driven by climate-induced drying of two southern boreal bogs over recent centuries.

Northern boreal peatlands are important ecosystems in modulating global biogeochemical cycles, yet their biological communities and related carbon dynamics are highly sensitive to changes in climate. Despite this, the strength and recent direction of these feedbacks are still unclear. The response of boreal peatlands to climate warming has received relatively little attention compared with other northern peatland types, despite forming a large northern hemisphere-wide ecosystem.

Transfer of transuranium elements along the food chain lichen-reindeer-man - A review of investigations in Finnish Lapland.

Following the atmospheric nuclear tests in the '50s and early '60s radioecological research on the (sub)arctic food chain lichen-reindeer/caribou-man was initiated in Finland among other northern countries. The enrichment of radionuclides in this food chain can lead to exceptionally high body burdens among the indigenous Sami and Inuit populations consuming large quantities of the meat and edible organs of reindeer and caribou. In Finland, first fission and activation products and natural radionuclides were studied but in the early 1970s' the investigations concerning transuranium elements were started.

Nuclear contamination sources in surface air of Finnish Lapland in 1965-2011 studied by means of Cs, Sr, and total beta activity.

Radionuclides Cs and Sr and total beta activity were determined from air filters collected in Rovaniemi (Finnish Lapland) in 1965-2011. Nuclear contamination sources present in the air filter samples as well as temporal changes in radionuclide concentrations were examined. Ozone observations and meteorological modeling were used in combination with radionuclide analyses to study the reasons behind the observed seasonal concentration variation.

Aerosol particle size distribution of atmospheric lead-210 in northern Finland.

Size-segregated aerosol samples were collected with a high-volume 6-stage cascade impactor at Sodankylä, Finland, 100 km north of the Arctic Circle. The Pb content of the samples were determined with radiochemical separation of in-grown Po followed by alpha spectrometry. Most of the Pb activity was incorporated in accumulation mode aerosol particles.

Airborne fission products in the High Arctic after the Fukushima nuclear accident.

High-volume aerosol samples were collected at the Mt. Zeppelin Global Atmosphere Watch station, Ny-Ålesund, Svalbard (78°58'N, 11°53'E). The samples were analysed to find out if the radionuclide emissions from the Fukushima nuclear power plant accident in March 2011 could be detected also in the atmosphere of the High Arctic.

Speciation of ¹²⁹I in sea, lake and rain waters.

Concentrations of the very long-lived fission product (129)I and stable iodine ((127)I) in the Baltic Sea and lake and rain waters from Finland, were measured as well as their occurrence as iodide (I(-)) and iodate (IO(3)(-)). The highest concentrations of both (127)I and (129)I occurred in sea water, on average 11.1 ± 4.

Overview of strontium-89,90 deposition measurements in Finland 1963-2005.

In Finland the deposition of strontium-89 (90Sr) and strontium-90 (90Sr) has been monitored since the early 1960s. The measured cumulative 90Sr deposition in 1963-2005 is on average 1200 Bq m(-2), of which 150 Bq m(-2) originates from the Chernobyl accident. Adding to this the deposition in 1945-1962 produces a value of 2040 Bq m(-2) for the cumulative deposition in Finland.

Deposition of gamma emitters from Chernobyl accident and their transfer in lichen-soil columns.

Lichen-soil column samples were taken from several locations in the Southern Finland between 1986 and 2006. Columns were divided into three parts, upper lichen, lower lichen and underlying soil, and their gamma emitting radionuclides, 134Cs, 137Cs, 103Ru, 95Zr, 106Ru, 110mAg, 125Sb and 144Ce, were measured with gamma spectrometry. Deposition values were calculated as Bq/m2 for each sampling site.

Identification of organic compounds in atmospheric aerosol particles by on-line supercritical fluid extraction-liquid chromatography-gas chromatography-mass spectrometry.

Atmospheric particles were collected with a high-volume sampling system at an urban site in Helsinki (Finland). The samples were analysed by on-line coupled supercritical fluid extraction-liquid chromatography-gas chromatography-mass spectrometry (SFE-LC-GC-MS). The aerosol sample was first extracted by SFE.

Ambient silver concentration anomaly in the Finnish Arctic lower atmosphere.

Mean silver concentrations in weekly particle samples collected at Kevo, northern Finland, were determined for the period of October 1964-March 1978 by neutron activation analysis. Two distinct periods were observed in the silver concentration levels over this time frame. During 1964-1970, mean weekly silver concentration levels were found in the range of 0.