Soil Chemistry for Environmental Assessments

Soil Chemistry coverage
Scale 1:50 000 or 1:10 000 (some urban areas)
Coverage Great Britain
Format GIS polygon and point data. (ESRI, MapInfo, others available by request)
Price £1.20 per km2 for all 5 elements. 30p per km2 for single elements. Subject to licence fee and data preparation fee.
More information about licensing data.

Potentially harmful chemical elements (PHEs), including arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb), can occur naturally in the environment and as a result of anthropogenic contamination. Under certain circumstances they can be harmful to plants, animals or people. Whether or not a particular PHE constitutes a hazard depends on a variety of factors including its chemical form, concentration, behaviour and the extent to which it may be taken up by living organisms; the size of the mineral particles in which the element occurs; soil or water acidity (pH); the type of vegetation cover; the extent of exposure to the element; and the dose received.

Some PHEs are widely distributed in natural (uncontaminated) soils as well as in a range of anthropogenic sources.

The Soil Chemistry for Environmental Assessments dataset contains estimated ambient background concentrations for the soils of Great Britain as well as locations and concentrations (mg kg-1) of As, Cd, Cr, Ni and Pb in urban surface soil samples, collected from soil geochemical surveys in 23 major urban centres. The urban soil chemistry data now includes estimated bioaccessible data for arsenic and lead. Bioaccessibility is an estimate of the fraction of the PHE released from the soil into solution in the gastrointestinal tract in a form that can potentially be absorbed into the bloodstream.

The data can be used together to establish whether elevated local measurements in urban areas are the result of significant anthropogenic contamination, or whether they are representative of the estimated ambient background concentration mainly related to soil parent material composition.

Reports generated from this spatial data will help to inform planning decisions and to aid environmental consultants, developers, householders and their legal representatives.

The dataset comprises of the following layers:

  • Estimated Ambient Background Soil Chemistry:
    This indicates the estimated geometric mean concentrations (mg kg-1) of total As, Cd, Cr, Ni and Pb in topsoil, and provides the likely geogenic background concentration of these PHEs.
  • Urban Soil Chemistry:
    This comprises two data layers:
    1) the locations and measured concentrations (mg kg-1) of total As, Cd, Cr, Ni and Pb in urban topsoil samples from 23 urban centres across Great Britain
    2) Estimated soil chemistry data derived by spatial interpolation of the measured urban data

This data can be used in conjunction with the Technical Guidance Sheets and Supplementary Information associated with the Contaminated Land Statutory Guidance for the Environmental Protection Act 1990: Part 2A, to assess whether concentrations of elements at a site fall within the 'normal' level.


Frequently Asked Questions relating to the Soil Chemistry for Environmental Assessments dataset.


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Hutton field: well correlation diagram.