Pragmatic approach for risk assessment screening of products containing manufactured nanomaterials

Despite poor traceability, the various sources of information on the state of the market for consumer products containing manufactured nanomaterials (nanoproducts) agree that this market is highly diversified and evolving rapidly. Indeed these products, which are found in many areas of application, vary greatly even within a given sector of use. The research efforts undertaken have helped advance knowledge about the risks associated with the uses of these nanoproducts. However, in addition to still being faced with considerable gaps in knowledge in risk assessment, the dynamics of acquiring the required specific data compete directly with those of the evolution (manufacturing processes, characteristics, uses, etc.) of these nanoproducts on the market. In such a context, major uncertainties remain regarding the assessment of the risks associated with their use. To address these difficulties, several alternative approaches to risk assessment – specifically developed for nanomaterials – as well as tools intended to guide risk management in such a context of uncertainty, are currently being proposed by different organisations. On the basis of their analysis, Anses produced on 2015 a semi-quantitative approach based method for assessing health risk levels and ecotoxicological hazards associated with common consumer nanoproducts uses. One of the main improvements offered by this proposed assessment method stand in analysis of the relevance of the results : in order to extract information from alternative data sources when no others are available (for example, combining in vitro data with relevant physico-chemical information instead of in vivo data) while emphasising the uncertainty introduced by the use of such data, the results of the assessment are accompanied by a degree of relevance characterising the level of confidence that should be attributed to them. Therefore, the results obtained are interpreted in terms of combination of risk levels with associated degrees of relevance. The authors emphasise that this methodological work, which constitutes the first version of an assessment method to be improved, may be used to categorise nanoproduct-use combinations, with regard to the health risks and ecotoxicological hazards, in order to: • select those that should undergo in-depth risk assessments; • enable a comparison of different nanoproducts intended for a similar purpose; • guide the research efforts with a view to removing the most damaging uncertainties. This method should also provide substantial help to the various stakeholders involved, mainly by enabling them to: • identify the parameters to be studied and provided to the authorities for the risk assessment; • anticipate potential risks when designing nanoproducts; • estimate the potential risks associated with uses of nanoproducts already on the market and contribute to their prevention; • define the most suitable means of prevention to reduce the risks to the lowest level reasonably possible.