BARGE banner - click to go to the BARGE home page
BARGE (the Bioaccessibility Research Group of Europe)

Diagram of a human digestive tractIn April 2000, the Contaminated Land Regulations in England and Wales (Environmental Protection Act 1990: Part IIA) came into force. This placed duties on local authorities to inspect their areas and to identify sites that fall into the definition of ‘contaminated land’, and required its assessment and remediation in line with the ‘suitable for use’ approach. In 2002 guidance, known as the Soil Guideline Values (SGVs), was published concerning the assessment of risks to human health from land contamination for a number of inorganic contaminants such as arsenic

In Britain naturally occurring elements and those present as a result of anthropogenic activities, such as arsenic, have been shown to be present in soils at concentrations above the newly introduced SGVs in a number of areas across the UK.

Risk assessments, have traditionally been based on the total concentration of the toxic substance present and more recently have included the use of bioaccessibility testing data.

Where bioaccessibility tests have been carried out, the resulting data have begun to be used as supporting data to provide a scientific basis for modifying the SGVs in light of site specific circumstances. As a result the use of bioaccessibility data could result in a substantial saving when compared with the costs of remediating large volumes of soil.

To ensure the quality and reproducibility of data produced by bioaccessibility tests for both bioaccessibility and total element data, the BGS has collected and prepared a reference soil for use by analytical laboratories.

Metalliferous mining works have left aSoil testing

As well as natural occurrence of potentially harmful elements, sources of anthropogenic soil contamination

The BGS has collected and prepared c. 500kg of naturally contaminated soil from North Lincolnshire. The soil is a ferritic brown earth, similar to the Banbury series. The reference soil has been dried, ground, homogenised and characterised at the BGS facilities in Nottingham. The reference soil contains a range of naturally occurring contaminants including arsenic and nickel. The reference soil is currently undergoing bioaccessibility testing for ‘consensus’ bioaccessibility values for a range of elements by a round robin exercise with UK laboratories and the Bioaccessibility Research Group of Europe (BARGE). Initial results indicate that the total arsenic concentration in the reference soil is c. 90 mg kg-1 and the measured bioaccessible arsenic content is c. 5 mg kg-1.

Soil investigationThe BGS is Britain’s national Geological Survey and one of the world’s major centres of geoscientific knowledge and expertise. The survey carries out a wide range of geoscience work for both the public and private sectors. Its research relates directly to energy, mineral and groundwater resources, land use, natural hazards and protection of the environment.

The BGS has extensive and modern laboratories covering a wide range of testing facilities with state of the art instrumentation. The range of testing capabilities is unique within UK organisations.

Dr Joanna Wragg, British Geological Survey, Keyworth, Nottingham, NG12 5GG

Tel: +44 (0) 115 936 3100 Switchboard

+44 (0) 115 936 3069 Direct Line

Fax: +44 (0) 115 936 3200