Site investigation and risk assessment for asbestos in gardens in Leeds
An ever growing number of councils are faced with the problem of asbestos turning up in people's gardens or allotments and the necessity to determine whether the asbestos represents a significant possibility of significant harm (SPOSH) to health. Under Part 2A of the Environmental Protection Act 1990, the existence of SPOSH necessitates remedial work to reduce the risk to health. Site remediation can be difficult enough before any houses are built but is trickier still once houses are built and occupied. There is also a risk that occupants may be more exposed to asbestos as a result of its removal than if it is left in situ and, if householders have to finance the remedial work, there are significant health issues associated with the resultant stress.
The IOM has recently completed an investigation of asbestos in garden soils for Leeds City Council (LCC). LCC had previously discovered asbestos contamination in a small number of soil samples from gardens in a housing estate built on the site of a former woollen mill known to have handled asbestos. In this investigation, we helped LCC by providing the information required to determine whether the presence of asbestos represented a significant possibility of significant harm (SPOSH) to health and whether gardens required remediation. We:- collected and analysed soil samples to determine the extent and severity of asbestos contamination across the estate;
- estimated the exposure of estate residents to airborne asbestos fibres both indoors and outdoors (e.g. while gardening) taking account of measured asbestos fibre concentrations in indoor air and using the newly available Advanced REACH Tool (ART) for exposure modelling; and
- determined the resultant cancer risks.
Overall, asbestos contamination in soil was low and patchily distributed. Other key findings included the absence of airborne asbestos fibres in indoor air or in settled dust inside properties where asbestos contamination was present in gardens. It was concluded on the basis of a quantitative risk assessment that the levels of asbestos found did not represent SPOSH.