Urban soil chemistry data for Great Britain

The British Geological Survey (BGS) urban soil chemistry dataset identifies areas of elevated topsoil concentrations of potentially harmful chemical elements (PHEs) and can be used in conjunction with proposed soil screening value (SSV) for assessing ecological risks and/or the soil guideline value (SGV), which is a threshold used in the preliminary assessments for land contamination. PHEs, including arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb), occur in the environment both naturally and as a result of human activities. Under certain circumstances these can be harmful to plants, animals or people. Whether or not a particular PHE constitutes a hazard depends on a variety of factors including, e.g. its chemical form (speciation), concentration, soil or water acidity (pH), the type of vegetation cover, the extent of exposure and the dose received. PHEs exist in a range of inorganic forms which have varying toxicity. Ambient background concentrations of PHEs in surface soil from natural and non-natural sources are required for: i) risk assessments and, ii) establishing whether elevated measurements may be the result of significant anthropogenic contamination.