Welcome Descriptive vs. Quantitative Risk Assessment of Genotoxic Carcinogens 2 nd April 2009

Descriptive vs. Quantitative Risk Assessment of Genotoxic Carcinogens A workshop to evaluate the benefits and disadvantages of the application of descriptive and quantitative methodologies to the assessment of risk of genotoxic carcinogens

IGHRC The Interdepartmental Group on Health Risks from Chemicals (IGHRC) is comprised of representatives from UK government departments, agencies and research councils with an interest in chemical risk assessment Full membership list available at:

IGHRC Activities IGHRC aims to reduce uncertainties and limitations in the conduct of chemical risk assessment through: development and publication of reports and guidance documents* as a means of promoting best practice, harmonisation and awareness of different risk assessment approaches among government departments and agencies establishing specific issue working groups to develop and share expertise the provision of training courses in the field of risk assessment *available from:

Workshop Agenda 1310Welcome and Introduction to the IGHRC Speaker: EC Chair/IGHRC Secretariat 1315COC Approach to Risk Assessment of Genotoxic Carcinogens Speaker: COC Chair 1335UK Approach to Risk Assessment of Genotoxic Carcinogens in the occupational setting Speaker: Dr Susy Brescia 1355Dealing with Genotoxic Carcinogens: the views of an EU-recognised expert Speaker: Prof Hermann Bolt 1415EFSA MoE Approach Speaker: Dr Sue Barlow 1435Dutch Approach to Risk Assessment of Genotoxic Carcinogens Speaker: Dr Dinant Kroese 1455US Approach to Risk Assessment of Genotoxic Carcinogens Speaker: Dr David Lovell 1515Tea/Coffee 1530Discussion Session – the benefits and disadvantages of the two approaches: Chair: Prof Len Levy 1615Consolidation Discussion – Next Steps 1630Close

Weight of evidence approach For genotoxic carcinogens, it is not possible, in practice, to identify a threshold level below which no effect would be expected. Extrapolation from relatively high dose levels used in animal studies in order to estimate probable responses at lower doses in humans is very uncertain. Predictions also give an impression of precision that cannot be justified in the light of the approximations and assumptions on which they were based. The policy generally adopted in the UK for risk management of genotoxic carcinogens is based on eliminating exposures or reducing exposures so that they are as low as is reasonably practical. Assessment of chemical carcinogens: Background to general principles of a weight of evidence approach cr 8

Discussion Session What are the current approaches adopted by UK government departments and agencies? How does this compare to the risk assessment methodologies used across Europe/internationally? What guidance has been produced? Do the descriptive and quantitative approaches have particular use scenarios? Does current guidance/opinion require further evaluation or summary?