Relevance and reliability of experimental data in human health risk assessment of pesticides.

Evaluation of data relevance, reliability and contribution to uncertainty is crucial in regulatory health risk assessment if robust conclusions are to be drawn. Whether a specific study is used as key study, as additional information or not accepted depends in part on the criteria according to which its relevance and reliability are judged. In addition to GLP-compliant regulatory studies following OECD Test Guidelines, data from peer-reviewed scientific literature have to be evaluated in regulatory risk assessment of pesticide active substances. Publications should be taken into account if they are of acceptable relevance and reliability. Their contribution to the overall weight of evidence is influenced by factors including test organism, study design and statistical methods, as well as test item identification, documentation and reporting of results. Various reports make recommendations for improving the quality of risk assessments and different criteria catalogues have been published to support evaluation of data relevance and reliability. Their intention was to guide transparent decision making on the integration of the respective information into the regulatory process. This article describes an approach to assess the relevance and reliability of experimental data from guideline-compliant studies as well as from non-guideline studies published in the scientific literature in the specific context of uncertainty and risk assessment of pesticides.

Zero tolerances in food and animal feed -- are there any scientific alternatives? A European point of view on an international controversy.

A number of zero tolerance provisions are contained in both food and animal feed law, e.g. for chemical substances whose occurrence is not permitted or is directly prohibited in food or animal feed. In the European Union, bans of this kind were introduced to give consumers and animals the greatest possible protection from substances with a possible hazard potential within the intendment of the hazard prevention principles and current precautionary measures. This also applies to substances for which an acceptable daily intake cannot be derived and a maximum residue limit cannot, therefore, be established, e.g. due to missing or inadequate toxicological data. Zero tolerances are also under discussion as trade barriers because their use has triggered numerous legal disputes. This paper draws together the results of an evaluation of alternative risk assessment methods to be used for the risk assessment of substances to which currently only zero tolerances apply. It will demonstrate that, depending on the available toxicological data, a scientifically sound risk assessment may still be possible. In this context, the two concepts - margin of exposure and threshold of toxicological concern - are very promising approaches. Until the scientific and sociopolitical discussions have been completed, it is essential that the principle of zero tolerances be upheld, especially for those substances which may be genotoxic carcinogens. In microbiology, there is no legal room for manoeuvre with regard to food safety criteria established for reasons of consumer health protection on the basis of scientific assessments.