Stream plant chemistry as indicator of acid sulphate soils in Sweden

Results from the biogeochemical mapping (roots of aquatic plants and Fontinalis antipyretica) conducted by the Geological Survey of Sweden (SGU) reflects the metal load of surface waters draining acid sulphate (AS) soils in Sweden. In this study, results from the biogeochemical, soil geochemical and Quaternary mapping programmes at SGU were used to investigate the impact of fine-grained deposits hosting AS soils on stream water trace element chemistry in two separate areas. In the area around Lake Mälaren, postglacial sediments contain the highest levels of most trace elements studied. Owing to the low pH of AS soils and subsequent leaching, levels of nickel (Ni), cobalt (Co), copper (Cu), sulphur (S), yttrium (Y), uranium (U), tungsten (W), and molybdenum (Mo) were significantly elevated in aquatic roots. Levels were lower in the Skellefteå area, which may be explained by lower concentrations in source deposits. Concentrations of arsenic (As) and lead (Pb) were normal or impoverished in biogeochemical samples from postglacial, finegrained sediment areas. Maps based on ratios (Ni:Pb or Y:Pb) in biogeochemical samples can, together with results from Quaternary mapping, be used to predict areas with AS soils in Sweden.vo

Biogeochemical data from SGU : properties and applications

Geochemical mapping is a technique that has been used all over the world for a multitude of purposes. The biogeochemical mapping programme conducted by the Geological Survey of Sweden (SGU) is mainly based on stream plant chemistry, which, opposed to mapping based on inorganic stream sediments or soils, is a method that is very uncommon. The stream plants are roots of Carex species, roots of Filipendula ulmaria, and whole plant samples of Fontinalis antipyretica. Samples are collected at an average density of one sample per 7 km2. In urban areas, where access to naturally growing stream plants often is difficult or impossible, transplants of F. antipyretica are used. This thesis aims to increase understanding of some fundamental properties of the biogeochemical data set, and to describe some applications. The focus of the applications described is related to environmental issues, but these can to some degree be extended towards mineral exploration as well. Three important properties studied and described are 1) analytical quality of the data, 2) effects of expressing contents on a dry weight basis instead of as residuals, and 3) species dependent responses. It is shown that the analytical quality for most elements used are quite good, at least for the parameters further studied in the thesis. Species dependent responses do exist, but only for a few of the parameters is the influence strong enough to cause problems during interpretation. The most pronounced effect is a significant enrichment of Mn and Co in F. antipyretica as compared to the other species. Some effects can also be seen on Ba and Zn, but not to the same extent. Incidentally, the problem is somewhat less pronounced if the residual method of expressing concentrations is used. This residual method is based on stepwise regression, where Mn is one of the independent variables. For all other elements, expressing contents relative to dry weight could not be determined to cause any negative effects. As the dry weight basis is very commonly used for expressing concentrations, for most elements it can and should be used instead of the residuals historically used. One problem, that has proved to be difficult to solve, is the presence of variable amounts of minerogenic matter in the samples. However, as there are excellent correlations between several of the parameters (e g Ti, Cr, Al, Si, Zr) and loss on ignition, the other parameters can be used to aid interpretation. Chromium is one example, where unusually high Cr:Ti ratios occur at several locations with metallurgical or other industrial activities. Active acid sulphate (AS) soils is another example of anthropogenic contamination of the environment. The AS soils are quite common in areas below the highest shoreline in Finland and Sweden. It is however quite difficult to determine exactly where they are located. The thesis demonstrates that biogeochemical data provides information that can be used to localize such areas, where the stream water regularly is acidic and metal rich. Here again, a ratio (Y:Pb or Ni:Pb) can be used in order to further amplify the signature. Yttrium and Ni have been shown to occur in elevated levels in stream water affected by active AS soils, whereas Pb-concentrations even tend not to increase, or even decrease. In a selected drainage basin, it is shown that transplants of F. antipyretica responds fairly well to the stream water typical for AS soils. The F. antipyretica transplants as well as the other biological media studied, stair step moss (Hylocomium splendens), also contribute to demonstrating that the urban areas are geochemically complex, there is no straightforward relationship to the other sampling media studied. As in the other examples demonstrated above, baseline information from till and other soils provide a valuable key to understanding the biogeochemical data set.Godkänd; 2009; 20091117 (mivu); DISPUTATION Ämnesområde: Tillämpad geologi/Applied Geology Opponent: Professor Reijo Salminen, Geological Survey of Finland Ordförande: Professor Björn Öhlander, Luleå tekniska universitet Tid: Fredag den 18 december 2009, kl 10.00 Plats: F 531, Luleå tekniska universitet</p

Environmental applications of biogeochemical data from Geological Survey of Sweden

The Geological Survey of Sweden, SGU, has carried out geochemical mapping for several decades. In 1983, two regional mapping programmes were initiated, aiming at a nation wide coverage. While one of the programmes, till geochemical mapping, was focussed mainly on production of regional baseline information for mineral exploration purposes, the second programme was more adapted to environmental issues. This second programme constitutes sampling of living matter (roots of Carex species, Filipendula Ulmaria, and the bryophyte Fontinalis Antipyretica) in minor streams, and is called biogeochemical mapping. Despite more than twenty years of mapping, several aspects of the method and its results still remain unexplored. Furthermore, results from the biogeochemical mapping programme have traditionally been expressed as residuals (contents in ash, contents of iron and manganese, and loss on ignition have been used as independent variables). This residual method however is not used in the Fontinalis antipyretica monitoring method developed by the Swedish Environmental Protection agency (SEPA), thus use of the SGU regional data set as baseline information in a SEPA context is very difficult. Therefore, a transition to dry weight is desirable. This however introduces several problems, e. g. for chromium. Following an introduction to the development and current status of the geochemical mapping programmes, two environmental applications of the biogeochemical dataset have been developed through a combination of statistical and geostatistical methods. In the first, subsets of the biogeochemical database have been created and used in order to determine possible species dependent effects, spatial correlation and influence of main elements like titanium, iron, aluminium, silica, and manganese on chromium. In the second, relations between the chemical composition of samples and areas known (and suspected) to host acid sulphate soils are studied. The species studied vary somewhat regarding metal contents. Such differences are assumed to be related to uptake mechanisms. However, for most elements the differences are much smaller than the spatial variance and the results from the mapping programme can be used without respect to species. Other geochemical databases (till and soil), as well as geological data, have been used in order to examine the geochemical properties of the biogeochemical samples, and factors affecting spatial distribution, e.g. relationships with quaternary deposits. Chromium contents in biogeochemical samples are strongly related to titanium, silica, zirconium and ash content. This correlation is not present in glacial till and other quaternary deposits. Normalisation of chromium by titanium is an efficient tool to separate anthropogenic point source pollution from chromium derived from natural sources. Acid sulphate soils have a strong impact on surface waters, and ecosystems therein. The metal contents of biogeochemical samples in two separate areas where acid sulphate soils occur display similar features as stream water. Of the elements studied, levels of yttrium, nickel, cobalt, zinc, sulphur, (and others) are significantly higher in samples collected in areas with postglacial clays and gyttja containing soils, deposits that are known to comprise acid sulphate soils. The metal content of the biogeochemical samples can be used in order to detect active acid sulphate soils.Godkänd; 2005; 20061211 (haneit)</p

Nationell kartläggning av arsenikhalter i brunnsvatten samt hälsoriskbedömning

Arsenik (As) är ett grundämne som förekommer naturligt i berggrunden. I områden med sulfidrika bergarter som vissa skiffrar och andra äldre sedimentbergarter kan arsenikhalten i vattnet vara över eller mycket över gränsvärdet för dricksvatten (10 μg As/l). Dricksvattnet från framför allt bergborrade brunnar kan därför utgöra en betydande källa till arsenikexponering. Drygt en miljon permanentboende och ungefär lika många fritidsboende har sin dricksvattenförsörjning från egen brunn. Antalet borrade brunnar ökar. Tidigare undersökningar har visat förhöjda till höga arsenikhalter i brunnsvatten, framför allt i bergborrade brunnar, i Skelleftefältet i Västerbotten, i ett stråk mellan Västerås och Enköping och kring Sollefteå. I flera län saknas i dagsläget helt information om arsenikhalter i grundvatten. Gränsvärdet för arsenik i dricksvatten baseras på livstidsrisken för cancer. Arsenik kan ge tumörer i hud, lunga och urinblåsa, möjligen även i lever och njure. De tidigaste symptomen på kronisk arsenikförgiftning är pigmenteringsförändringar i huden och förtjockning av hudens hornlager framför allt på handflator och fotsulor. Risken för negativa hälsoeffekter minskar om exponeringen minskar eller upphör. Det är således önskvärt att begränsa intaget av arsenik så långt det är möjligt. Detta gäller speciellt för barn, eftersom experimentella studier tyder på att foster och små barn kan vara känsligare än vuxna. Inom ramen för den nationella hälsorelaterade miljöövervakningen analyserades under 2004 arsenik i 199 brunnsvattenprover tagna före eventuella filter. I denna rapport redovisas även resultaten från arsenikanalyser utförda vid SGU 2001-2003 (totalt 178 brunnsvatten). Sammantaget redovisas arsenikanalyser för 377 brunnsvatten från 14 län och 97 kommuner. I några län har endast ett fåtal prov tagits. Syftet med undersökningen var att kartlägga arsenikhalter i enskilda brunnar samt att sätta uppmätta halter i relation till kända risknivåer och göra en hälsoriskbedömning. Arsenikhalterna var låga i del flesta län. I 4,8% av brunnarna var arsenikhalten högre än 10 μg/l (range 11-297 g/l) och i 1,9% av brunnarna var halten högre än 100 μg/l (range 108-297 g/l). De högsta halterna uppmättes i Västerbotten (297 μg/l), Stockholm (max-halt 231μg/l) och Västmanlands län (25 μg/l). Arsenikhalter strax under gränsvärdesnivån 10 μg/l uppmättes i Jämtland, Norrbotten och Västernorrlands län samt på Öland. I övriga län låg alla uppmätta arsenikhalter under 10 μg/l. Syfte Att kartlägga arsenikhalter i enskilda brunnar samt att sätta uppmätta halter i relation till kända risknivåer och göra en hälsoriskbedömning

GEOCHEMISTRY OF EUROPEAN BOTTLED WATER

In Europe, ca. 1900 "mineral water" brands are officially registered and bottled for drinking. Bottled waters is groundwater and is in large parts of the continent rapidly developing into the main supply of drinking water for the general population. This book is the first state of the art overview of the chemistry of groundwaters from 40 European countries from Portugal to Russia, measured on 1785 bottled water samples, equivalent to 1189 distinct bottled water brands from 1247 wells in 884 locations plus an additional 500 tap water samples acquired in 2008 by the network of EuroGeoSurveys experts all across Europe. In contrast to previously available compilations, all chemical data (contained on the enclosed CD) were measured in a single laboratory, under strict quality control with high internal and external reproducibility, affording a single high quality, internally consistent dataset. More than 70 parameters were determined on every sample using state of the art analytical ..

URBAN GEOCHEMICAL STUDIES IN EUROPE

Urban soil is generally contaminated to a variable degree depending on its proximity to contamination sources. Traffic is one of the main sources of urban contamination; lead (Pb) from the use of leaded petrol, zinc (Zn) and cadmium (Cd) from tyre wear, antimony (Sb) from break pads, and the platinum group elements (PGEs) from the wear of catalytic converters, are some typical elements that often reach high concentrations in the urban environment. Lead was also a key ingredient in white paint, and in towns with a high proportion of white wooden houses very high concentrations were found in soil. Crematoria can or have emitted mercury (Hg). Coal and heavy oil fired municipal power and heating stations emit sulphur (S), silver (Ag), vanadium (V), bromine (Br) and barium (Ba). The use of impregnated wood may have resulted in high concentrations of arsenic (As), especially in kindergartens (nursery schools) and playgrounds. Building materials (plaster and paint) may also contain high concentrations of organic contaminants, especially polychlorinated biphenyls (PCBs), which again end up in urban soil. Coal and wood burning, the use of diesel fuel, and the production of coke, all lead to the emission of polycyclic aromatic hydrocarbons (PAHs). There exist countless other sources of local contamination in towns, and there is thus every reason to be concerned about the quality of the urban environment, and the suitability of soil for sensitive land uses, such as schools, playgrounds, parks and vegetable gardens. Contaminated urban soil may contaminate indoor dust and, therefore, to an increased human exposure to toxic chemicals. Consequently, the distribution of toxic contaminants in urban soil needs to be documented and known by city administration to avoid costly mistakes in land use planning, and further spreading of highly contaminated materials. The EuroGeoSurveys \u2018Geochemistry\u2019 Expert Group during the compilation of a proposal to the Directors for a European wide urban geochemistry project, using a harmonised sampling and analytical methodology, it discovered that many urban geochemical studies have been performed in Europe by National Geological Surveys, which are not known to the wider geoscientific community. Since, the results of these studies are directly related to our quality of life, the EuroGeoSurveys \u2018Geo chemistry\u2019 Expert Group decided to publish at least one case study from each country in a book,which will be available in the second half of 2010. A concise description of some of these studies will be given in this paper

Geochemical atlases of Europe produced by the EuroGeoSurveys Geochemistry Expert Group: state of progress and potential uses.

An ‘Atlas’is a collection of maps usually published in a book form. A ‘Geochemical Atlas’is a thematic special purpose atlas with maps describing the geographical distribution of chemical elements and other physico-chemical parameters in different natural sample media, such as stream sediment, overbank or floodplain sediment, stream water, ground water, soil, plants, etc. Because our standard of living and health depend closely on the chemistry of near-surface materials, such atlases that provide data on the state of our environment are important for policy and decision makers, but also for researchers and citizens alike. The EuroGeoSurveys Geochemistry Expert Group is dedicated to provide harmonised multi-purpose geochemical data bases, and has already published the Geochemical Atlas of Europe, and is in the process of preparing the Atlas of Ground water eochemistry of Europe, and the Atlas of Agricultural and Grazing Land Soils. An important aspect is that all raw data, quality control information, statistics, maps and interpretation texts are freely available for downloading through the internet