Closing the GAP Between Hazard Testing and Risk Assessment

DISCUSSION CLOSING THE GAP BETWEEN HAZARD TESTING AND RISK ASSESSMENT 

Application of the HRF increases the transparency of delineation of the relative degrees of nncertainty associated with various options for considraation in assessment of risk for impacted populations. HRFs are also instrumental in acquiring transparency on critical data gaps that will further reduce uncertainty. They force distinction of choices made on the basis of science policy versns those that are science jndgment related, inclnding reliance on default, based on the erroneous premise that it is always health-protective (Meek and Doull 2009). They focus on early events in a toxicity pathway through relation of early perturbations to apical endpoints in frameworks designed to systematically address (a) consideration of key events in modes of action and (b) their snbseqnent implications for dose-response in risk assessment [see, for example. Meek (2008)]. 

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and Tennant, R. W. (1994). Prediction of rodent carcinogenicity for 44 chemicals Results. Mutagenesis 9, 7-15. 

Boobis, A. R., Cohen, S. M., Dellarco, V., McGregor, D., Meek, M. E., Vickers, C., Willcocks, D., and Farland, W. (2006). IPCS framework for analyzing the relevance of a cancer mode of action for humans. Crit Rev Toxicol 36, 781-792. 

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