Synopsis
In 1992, the National Health and Medical Research Council (NHMRC) and the Australian and New Zealand Environment and Conservation Council developed guidelines for the assessment and management of contaminated sites. However, it was recognised at that time that further consideration was needed to develop a method for determining acceptable levels of carcinogenic soil contaminants. In 1995, the NHMRC established a Technical Working Party to develop a method for assessment of cancer risk that is appropriate for contaminated sites in Australia.
To overcome limitations in existing risk assessment methodologies for carcinogenic soil contaminants, the Technical Working Party have developed a method that determines a benchmark dose to which is applied a number of safety factors, in order to obtain an acceptable safe dose. The safety factors are based on scientific assessment of all the available knowledge about a chemical and its effects. In this method, no assumptions need to be made about what may or may not happen at doses well below the levels that have actually been tested experimentally.
This methodology was endorsed by the NHMRC at its 133rd Session, 6-7 September 1999.
