Application of arsenic baselines in the assessment of soil contamination in Finland

Abstract

In Finland, a new Government Decree on the Assessment of Soil Contamination and Remediation Needs (214/2007) came into force on 1 June 2007. According to the Decree, natural baseline concentration levels should be taken into account when assessing potential soil contamination and the need for remediation. This applies particularly in the case of toxic metallic elements, since baseline concentrations may naturally be rather high. The new decree prescribes soil screening values for 52 substances or groups of substances. The natural baseline concentrations have been taken into account in the definition of the screening values for inorganic pollutants. The Geological Survey of Finland (GTK) carried out a nation-wide geochemical mapping of till on a reconnaissance scale in 1983 and on a regional scale during 1984-1992. These surveys have provided information on natural elemental distribution in subsoils of the glacial till. However, some important trace elements in regional mapping such as arsenic are missing from the analysis, and subsoil samples do not reflect the diffuse anthropogenic input. Thus, GTK has continued the survey work by determining geochemical baselines around suburban areas. Samples have been taken from humus, topsoil and subsoil layers, and the soil parent material has covered sandy soils, glacial tills and fine-grained sediments. According to the studies, a regional difference in the levels of arsenic and some other trace elements can be clearly seen, especially in minerogenic soils. The results illustrate the importance of information on regional baseline concentrations while assessing potential soil contamination.

Source Apportionment of Chemical Elements and Their Geochemical Baseline Values in Surface Water of the Parauapebas River Basin, Southeast Amazon, Brazil

“…Evidence of this is the positive correlation between Ca, Mg, Na and K and pH. Different methodologies have been suggested in the literature to determine baseline values [2,3,10,11,14,[68][69][70][71][72][73][74][75][76][77], however, the best way to estimate these values is not clear. Therefore, several authors have used multiple methodologies and critically examined the different baseline/background values obtained [2,3,[68][69][70][71][72].…”

The spatial distribution of multiple elements in the Kanto region of Japan: Transport of chalcophile elements from land to sea

“…A number of studies have focused on specific areas, such as conducting the environmentally oriented geochemical mapping on soil substances in urbanised areas (Cicchella et al, 2008;Jarva et al, 2008;Johnson and Ander, 2008;Johnson et al, 2011;Li et al, 2004;Thornton et al, 2008). The spatial distribution of pollutants in the marine environment, including within harbours, inner bays, and coastal seas has been examined by Buckley and Winters (1992), Fang et al (2009), Leoni and Sartori (1996), Li et al (2001), and Whalley et al (1999).…”

Chemical Characterization of Metal-Contaminated Soil in Two Study Areas in Finland

“…Here, the baseline concentration refers both to the natural geological background concentration and the diffuse anthropogenic input of elements. Attention should also be given in the assessment to ambient environmental parameters (surficial material and groundwater conditions), current and future anticipated land use activities at and adjacent to the site, the potential for short-term and long-term exposure to substances in the soil, the severity and likelihood of health and environmental effects from this exposure, and the elements of uncertainty in the data and assessment methods used (Ministry of the Environment 2007; Jarva et al 2008).…”

“…Soil is regarded as contaminated, unless otherwise indicated in the risk assessment, if the guideline value is exceeded. The upper guideline values are applied at industrial or similar insensitive sites and the lower guideline values in the case of other land use (Reinikainen 2007;Jarva et al 2008).…”