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Potential health effects of contaminants in Soil - SP1002

Description
Part 2A of the Environmental Protection Act 1990 came into force in England in 2000. Its main aim is to help address the problem of historical contamination of land and the risks it can pose to people's health and the environment. Local Authorities are required to identify contaminated land and ensure that significant risks are dealt with. The legal definition of contaminated land encompasses land where substances in, on or under the land are causing significant harm or have significant possibility to cause harm as well as land causing or likely to cause pollution of controlled waters. Harm with respect to human health is assessed using quantitative risk assessment which considers: concentrations of contaminants in soil, water and air associated with the site; potential exposure of humans to the contaminants; the dose of contaminant that may be taken up by humans; and the health response that may be imparted by that dose.

This research project will address two important issues associated with UK policy on contaminated land. The first is that estimates of risk of health impacts from contaminated land do not quantify the very large uncertainties associated with assessing exposure, calculating dose and inferring potential health impacts. Instead, this uncertainty is compensated through the use of conservative estimates of exposure and the application of uncertainty factors to toxicological data; both approaches aim at yielding a protective estimate of potential health impacts associated with a particular site. The project will analyse uncertainties associated with health impacts from contaminated land and then target quantification of levels of uncertainty for risks associated with a case study contaminant. Results will provide information on the extent to which current risk estimates may be under- or over-protective of human health. They will identify the most important areas of uncertainty and thus help to target data collection and future research activities to reduce uncertainty.

The second issue is that action on health risks associated with contaminated land (i.e. decisions on labelling land contaminated and determining appropriate levels of clean-up) operate in isolation of information on the broader risks to human health. For example, one might hypothesise that total impacts on human health associated with air pollution from road transport are several orders of magnitude larger than those associated with exposure to contaminated land. This might then prompt questions about the relative costs to mitigate health impacts via the two sources and thus inform a debate about the relative costs and benefits of different policy options. The project will generate information on total health impacts from contaminated land and then compare this with health risks from other sources. This will provide a baseline analysis from which policy debate can be initiated.

The overall aim of this project is to provide an overview of the direct and indirect impacts of contaminated land on human health and compare the risks of suffering ill health due to land contamination to risks from other activities or sources of exposure.

The specific objectives are to:
1. Provide an overview of the different types of risk to human health posed by contaminated land.
2. Assess uncertainty associated with determining health impacts from contaminated land and undertake quantitative uncertainty analysis for four case study contaminants.
3. Estimate the overall risk to human health due to exposure to contaminated land, including likely levels of uncertainty.
4. For four case study contaminants, compare risks to human health from exposure to contaminated land with those from other sources of exposure to the contaminants.
5. Compare overall risk to human health from exposure to contaminated land with other risks to human health.
6. Consider the potential health implications that may arise from labelling land contaminated.

Objective
The overall aim of this project is to provide an overview of the direct and indirect impacts of contaminated land on human health and compare the risks of suffering ill health due to land contamination to risks from other activities or sources of exposure.

The specific objectives are to:
1. Provide an overview of the different types of risk to human health posed by contaminated land.
2. Assess uncertainty associated with determining health impacts from contaminated land and undertake quantitative uncertainty analysis for a case study contaminant.
3. Estimate the overall risk to human health due to exposure to contaminated land, including likely levels of uncertainty.
4. For a case study contaminant, compare risks to human health from exposure to contaminated land with those from other sources of exposure to the contaminants.
5. Compare overall risk to human health from exposure to contaminated land with other risks to human health.
6. Consider the potential health implications that may arise from labelling land contaminated.
Project Documents
• Final Report - Annex : Objective 1: Overview of risks to human health posed by contaminated land   (280k)
• Final Report - Annex : Objective 2: Uncertainties in assessing risks to human health from contaminated land   (808k)
• Final Report - Annex : Objective 3: Estimation of the overall risk to human health from contaminated land   (211k)
• Final Report - Annex : Objective 4: Quantification of other sources of exposure to the case study contaminants   (139k)
• Final Report - Annex : Objective 5: Compare overall risk to human health from exposure to contaminated land with other risks to human health   (54k)
• Final Report - Annex : Objective 6: Consideration of the potential health implications of labelling land contaminated   (84k)
• Final Report - SID5A : Potential health effects of contaminants in soil   (75k)
Time-Scale and Cost
From: 2009

To: 2009

Cost: £56,177
Contractor / Funded Organisations
Central Science Laboratory
Keywords
Environmental Protection              
Land              
Soils