The chemistry of Norwegian groundwaters: IV. The pH-dependence of element concentrations in crystalline bedrock groundwaters.

A total of 1604 samples of crystalline bedrock groundwaters in Norway have been analysed for pH, major and minor elements. A subset of 476 samples were also analysed for a wide range of trace elements by ICP-MS. The pH of the samples ranges from 5.4 to 9.8, with a predominance of pH values between 8.0 and 8.2. The data-set is divided into five 20-percentile groups according to increasing pH. The concentrations of 60 elements are then displayed as box-plots for each pH group. A line through the five medians yields a visual demonstration of the relationship with, and sensitivity to, pH variations for concentrations of each element. Twelve characteristic trends are distinguishable, from which some of the main hydrogeochemical processes related to pH and groundwater evolution can be inferred.

Baltic soil survey: total concentrations of major and selected trace elements in arable soils from 10 countries around the Baltic Sea.

Agricultural soils were collected from 10 European countries over a 1,800,000 km2 area surrounding the Baltic Sea. The sampling density was 1 site/2500 km2. Two samples were taken at each site: topsoil 0-25 cm (ploughing layer, Ap-horizon) and subsoil (bottom samples, usually B- or C-horizon) at an approximate depth of 50-75 cm, well below the ploughed layer. The samples were analysed for total element concentrations of 41 elements by WD-XRF. Analytical results for both layers are quite comparable. Large differences between element concentrations and variations can be observed for most elements when the different countries are compared. The Nordic countries show considerably higher concentrations and variations for quite a number of elements [Al, Fe, (Mg, P), Ti, Ba, Sc, Sr, V] in their agricultural soils. This is an expression of geology, the relatively younger age of the soils here and of the climatic conditions (reduced weathering rates). Regional geochemical maps demonstrate that geology overwhelmingly dominates the total concentration of chemical elements as observed in the agricultural soils. The three (four) large tectonic units (Caledonian mountain chain, Fennoscandian Shield and the northern and southern eastern European Platform) composing this area are all reflected in the regional maps.

The chemistry of Norwegian groundwaters: III. The distribution of trace elements in 476 crystalline bedrock groundwaters, as analysed by ICP-MS techniques

Four hundred and seventy-six groundwater samples from boreholes in Norwegian crystalline bedrock have been analysed by ICP-MS techniques. The results for 53 trace elements are presented as cumulative frequency distribution diagrams and are compared with relevant international drinking water norms. A range of trace elements appear to be enriched in granitic waters and depleted in anorthositic waters which is to be expected as generally granitic rocks are enriched in trace elements above those in anorthosites. A selection of elements which may be toxic in excess when present in drinking water are further discussed (Be, Tl, Th, U, Cd, Pb, As, Ni, and Hg). For uranium, 18% of the samples exceed the American maximum admissible concentration of 20 micrograms/l; 7% of the samples fail to meet the Russian drinking water norms for beryllium of 0.2 microgram/l. For some parameters such as U, Be and Tl, no Norwegian drinking water regulations are set, while the American and the Russian norms differ significantly from each other. Between 0 and 1.5% of the wells exceed Norwegian drinking water norms for each of the other selected elements.

Does bottle type and acid-washing influence trace element analyses by ICP-MS on water samples? A test covering 62 elements and four bottle types: high density polyethene (HDPE), polypropene (PP), fluorinated ethene propene copolymer (FEP) and perfluoroalkoxy polymer (PFA).

Groundwater samples from 15 boreholes in crystalline bedrock aquifers in South Norway (Oslo area) have been collected in parallel in five different clear plastic bottle types (high density polyethene [HDPE], polypropene [PP, two manufacturers], fluorinated ethene propene copolymer [FEP] and perfluoroalkoxy polymer [PFA]. In the cases of polyethene and polypropene, parallel samples have been collected in factory-new (unwashed) bottles and acid-washed factory-new bottles. Samples have been analysed by ICP-MS techniques for a wide range of inorganic elements down to the ppt (ng/l) range. It was found that acid-washing of factory-new flasks had no clear systematic beneficial effect on analytical result. On the contrary, for the PP-bottles concentrations of Pb and Sn were clearly elevated in the acid-washed bottles. Likewise, for the vast majority of elements, bottle type was of no importance for analytical result. For six elements (Al, Cr, Hf, Hg, Pb and Sn) some systematic differences for one or more bottle types could be tentatively discerned, but in no case was the discrepancy of major cause for concern. The most pronounced effect was for Cr, with clearly elevated concentrations returned from the samples collected in HDPE bottles, regardless of acid-washing or not. For the above six elements, FEP or PFA bottles seemed to be marginally preferable to PP and HDPE. In general, cheap HDPE, factory new, unwashed flasks are suitable for sampling waters for ICP-MS ultra-trace analysis of the elements tested.

Influence of filtration on concentrations of 62 elements analysed on crystalline bedrock groundwater samples by ICP-MS.

Analyses of unfiltered and filtered (< 0.45 micron and < 0.10 micron) groundwater samples from 15 selected wells in crystalline bedrock aquifers of the Oslo area, Norway, have been studied for 62 chemical elements. While concentrations of almost all elements vary over several orders of magnitude between the individual wells, the discrepancy between filtered and unfiltered samples from the same well are rather small, not exceeding one order of magnitude. Many elements show no influence of filtration at all, while one element (Sn) suggests that filtration may actually introduce contamination to the samples. Correlation between unfiltered and filtered samples is high for most elements. The study shows that: (1) even unfiltered samples will satisfactorily reflect general water chemistry as long as drinking water (i.e. by definition rather 'clean' water, with low particulates) is collected; (2) filtered samples do not necessarily reflect 'true' solution chemistry (an elusive concept); and (3) the differences between samples filtered at < 0.45 micron and < 0.10 micron are so minimal for most elements, that the additional effort invested in ultra-filtration may not be justified for bedrock groundwater samples.

Variation of 66 elements in European bottled mineral waters.

Fifty-six bottled mineral waters bought at random all over Europe were analysed for 66 chemical elements by ICP-AES, ICP-MS and IC-techniques. Results show that there is a wide spread in the chemical composition of mineral waters. The EEC drinking water safeguard values for chemical constituents do not apply to mineral water, although mineral water is increasingly used for general drinking water purposes. Only 15 of the randomly selected 56 mineral waters would fulfil the drinking water regulations for all parameters where action levels are defined. Differences in chemical composition observed between countries or regions are due to geological environment and to different taste or local regulations of what is mineral water. There are indications that element concentrations for some unwanted constituents (e.g. Pb) are higher in waters sold in glass bottles than in those in plastic bottles. Some elements show a clear regional dependency. Studying the large natural variation in concentration for many of the 66 studied elements it becomes clear that we know little about the natural variation of element concentration in water and the health effects of most elements in drinking water.

[Ground water and health. Reflections based on analysis of water specimens from Hordaland and Vestfold]. / Grunnvann og helse. Refleksjoner på grunnlag av analyse av vannprøver fra Hordaland og vestfold.

Basically, Norway has an ample supply of water. The quality of Norwegian drinking water, however, is threatened, not the least because of pollution of surface water reservoirs. Ground water is better protected against pollution, and sub-surface water sources are being exploited more than before. At present, less than 15% of the Norwegian population uses ground water for household purposes, but the percentage is increasing rapidly Ground water is (normally) clean and has a good taste. A large number of elements can be traced in ground water; some of them in concentrations of significance for human health. The present paper reports elemental analyses of 150 water samples from ground water reservoirs in rock, collected in Vestfold (Eastern Norway) and Hordaland (Western Norway). Sixty-four elements were assessed using modern equipment such as ICP-MS. In most cases the chemical composition of the water was well within the limits set for good quality drinking water. For some of the elements one or more of the results exceeded the "highest acceptable concentrations" as defined by the Norwegian health authorities. This was the case for Al, As, Ba, Ca, Cd, F, Fe, Hg, K, Mg, Mn, Na, P, Pb, Rn and Zn. No drinking water standards have been established for Be, Mo, Th and U, which are of clear significance to the health. More research is needed to assess the relationship between drinking water chemistry and human health. The authors call for a systematic analysis of all Norwegian ground water wells, and emphasise the need for regular quality control, even of small, private water supplies.

Radon, fluoride and 62 elements as determined by ICP-MS in 145 Norwegian hard rock groundwater samples.

Hard rock groundwater (145) samples collected from private drinking water wells in the environs of Oslo and Bergen were analysed for their radon and fluoride contents. A further 62 elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). For 59 elements, more than 50% of all concentration values were above the detection limit. Characteristic differences between the Oslo- and Bergen-dataset can be shown to be related to host rock lithology. Variation in element contents generally spans 2-6 orders of magnitude. Concentrations of several elements (e.g. Ba, F, Fe, Mn, Na, Rn) exceed current drinking water action levels in a significant number of cases. High levels of other parameters such as Be, Mo, Th and U, which could have an impact on health, were observed. There are no Norwegian action levels currently defined for these elements. The economic and toxicological impacts of these findings require urgent assessment.

The German heavy metal survey by means of mosses.

This is the first attempt to determine pollution with metals throughout the Federal Republic of Germany by analysing moss samples. Samples of Pleurozium schreberi, Scleropodium purum, Hypnum cupessiforme and Hylocomium splendens were collected at 593 sites and analysed by ICP-AES and AAS for the elements As, Cd, Cr, Cu, Fe, Ni, Pb, V and Zn. Citrus leaves and pine needles were used as reference materials to ensure the quality of the results. In many cases it was possible to trace the areas affected by known sources of heavy-metal emissions in addition to isolated local increases in the values. The moss monitoring programme showed up the highly industrialized and urban locations such as the Ruhr, parts of the Saarland and Baden-Wurttemberg and large areas of eastern Germany. Lower levels of many elements were found in wide stretches of Lower Saxony and Bavaria. The results largely reflect the pollution patterns found in these areas. On the other hand, expected correlations between the effects of traffic (e.g. Pb) and concentrations in moss could not be demonstrated with certainty. The element data yielded by this project are Germany's contribution to the European project 'Atmospheric Heavy Metal Deposition in Europe -- Estimations based on Moss Analysis'.

Catchment acidification-from the top down.

Three main factors define the speed of catchment acidification: the total input of pollutants; the thickness and character of soils, including the nature of the bedrock; and the size of subcatchments. The aerial input of pollutants in the Harz is among the highest in Central Europe (e.g. SO4-S: 22-70 kg (ha year)(-1); NO3-N: 9-10 kg (ha year)(-1); NH4-N: 10-15 kg (ha year)(-1) and Cd: 2.6-8.7 g (ha year)(-1); Cu: 34-125 g (ha year)(-1); Pb: 150-380 g (ha year)(-1); Zn: 105-560 g (ha year)(-1)). Thick soil profiles (2-4 m) acidify from the top down. Whether the soils will neutralize incoming acids depends on their buffering capacity. The small headwater subcatchments acidify first and subsequently release acidic water with pH values down to < or = 40. Four brook zones can be divided by the composition of their biocoenoses. The latter depend on the degree of acidification. These zones are also characterized by different hydrochemical conditions.