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An important shortcoming in our present knowledge required for risk assessment of biocidal products is the assessment of human exposure. This knowledge gap has been filled in a preliminary fashion with the TNsG on human exposure to biocidal products (available from the ECB website). Explicit User guidance has been developed by an expert group for a general approach of the exposure assessment and in appreciable detail for me first two product types wood preservatives and rodenticides. This User guidance is also available from the ECB website. Further additions for other product types are foreseen for the near future.

Gehouden op de NVvA symposium 28 en 29 maart 2002.

The health risk to the agricultural worker using pesticides is important for registration procedures since during mixing, loading and application he or she handles undiluted as well as diluted pesticide formulations. Furthermore, exposure may occur during daily activities in the crop (e.g. harvesting). Possible exposure may reach levels that lead to excessive health risks depending on the toxicity of the pesticide. In such cases measures to ensure safe handling have to be prescribed. In the present paper the published data, based on exposure occurring in agricultural practice, are considered for extrapolation to obtain surrogate exposure levels for risk assessment in registration procedures. The criteria necessary for the input of exposure data in data-bases, and the scope for extrapolation and its drawbacks, will be discussed. The various exposure models that have been described will be discussed and compared, and illustrated with a few cases.

For registration of agricultural pesticides, the risks for humans, animals, and the environment must be determined. The risk assessment is based on an appraisal of the levels of exposure and the hazards of the active substance(s) in the plant protection product, that is, the agricultural pesticide. Funded by the European Commission (AIR3 CT93-1370), the EUROPOEM database has been developed by a group of experts, representing governments, industry, and academia. The currently available exposure database reflects exposure to operators (mixer/loaders and applicators). The EUROPOEM approach is based on a harmonized protocol for conduct of field studies of operator exposure (presently published as an Organization for Economic Cooperation and Development [OECD] Guidance Document) and a tiered approach to exposure and risk assessment. The database is constructed from exposure data obtained in representative field studies. These field studies are considered according to criteria reflecting the quality of documentation, study design, adequate methodology, number of replicates, and QA/QC elements, for use of the inhalation and dermal exposure data. The resulting exposure data were combined according to comparable use scenarios. From the resulting databases typical surrogate potential exposure values have been obtained, which are determined by their use for either acute or chronic health effects, and the size of the database. For large databases (over 50-100 data points), from many different field studies (10 or more), the 75th percentile is taken if the exposure is considered leading to chronic effects. For smaller databases, a more conservative 90th percentile is taken as surrogate value, or none at all for very small databases (15-20 or less data points from 3 or less different field studies). The choice for the 75th percentile is based on the assumed or observed log-normal distribution of the exposure data, as being the most relevant typical value for long-term effects, since the 75th percentile of log-normal distributions is nominally very similar to a calculated arithmetic mean (AM). The AM, as such however, is irrelevant for log-normal distributions. Chemicals/CAS: Pesticides

In a project granted by DG XI of the European Commission, it is attempted to collate experimental and theoretical data on human (workers and consumers) exposure assessment to biocidal products, and to outline the methodology for sampling and measurement. On the basis of the available evidence, approaches are presented for the exposure assessment to be used for estimation of risks in authorization procedures under the recently accepted Directive 98/8/EC. Gaps in knowledge are indicated, making it possible to study the issues involved in a comprehensive and cost-effective way. Some recommendations are given on how to best do this. The current project has been detailed in a final report. Copyright (C) 1999 Elsevier Science Ireland Ltd.

Dermal exposure to industrial chemicals during work is of major concern in the risk assessment of chemicals. Current approaches in procedures for European legislation are not based on experimental data of dermal exposure in the workplace because they are lacking. A project was funded to overcome this problem. In this paper an overview is given of an important part of the project: the development of a risk assessment and risk management Toolkit for dermal exposure. The Toolkit assesses potential risk of dermal exposure for workplaces, especially in small and medium enterprises. The Toolkit contains textual information on the skin and on (risks of) skin exposure, and is available from the net and on CD-rom.

Chemicals / CAS: 4,4' methylenedianiline, 101-77-9; Hazardous Substances.

Chemicals/CAS: Pesticides

For registration of pesticides data on toxicology and on occupational exposure are required. In this series of reviews the exposure data available in the published literature for mixing and loading, application and re-entry are considered for the establishment of generic/surrogate data bases with which for a specific case (e.g. a new pesticide) the exposure can be estimated for use in a first step for risk assessment. In the first part of the series the general aspects of the determination of exposure to pesticides under field conditions are considered, as well as the published proposals for generic data bases. It is concluded that the development of data bases in principle possible, although in many cases (depending on the type of technique for mixing/loading and application) not enough data are available. Data bases on re-entry have not been proposed in the literature, although many studies on exposure after re-entry have been reported. A general approach to risk assessment using (surrogate) exposure data is described.