On 17 and 18 April, Akademie Fresenius opened the doors on their 16th International Conference “Food Safety and Dietary Risk Assessment” in Mainz. Top-ranking European experts discussed the latest trends and techniques in the area of residue analysis. One of the main focal points of the conference was the assessment of the risks to humans through multiple contaminants. The information received by the participants included a status report from the working group on the harmonisation of risk assessment methodologies at the European Food Safety Authority.
Foodstuffs can contain a range of substances that may be potentially harmful to health – for example, environmental contaminants and pesticide residues. Assessing the health risk of such chemical mixtures is complicated. As a rule, toxicological data is only available for individual substances - rarely for complex mixtures. The cumulative risk assessment of chemical mixtures, therefore, is currently one of the major challenges facing toxicologists and risk assessors.
Desired by all: A unified, European-wide approach to assessing chemical mixtures
Alan R. Boobis of Imperial College London provided an overview of current approaches for assessing chemical mixtures. He stated that there was currently no overarching approach in place for assessing cumulative risks from chemicals although some organisations, such as the OECD, were working on this. It is always a trade-off: How can consumer protection be successfully ensured without unnecessarily restricting the international food trade? First and foremost, Boobis considers it necessary to define principles at European level which are used to group chemicals together for the various risk assessment purposes: ‘The basic principle for an assessment group must be clearly defined – whatever the basis used.’
EuroMix: measureing and assessing the risk of mixtures
Jacob van Klaveren of the Dutch National Institute for Public Health and the Environment (RIVM) reported on where the EuroMix project (European Test and Risk Assessment Strategies for Mixtures) currently stands. Scientists from 15 countries are presently collaborating on this project. The aim of the EuroMix project is to develop tests that are able to better determine the toxicity of mixtures and the second aim is to provide a web-based model and data platform to assess the risk of combined exposure to multiple chemicals via multiple exposure routes. One key aspect of this work is to refine the EFSA methodology on cumulative risk assessment of pesticides, but EuroMix will also address the risk of exposure to other chemical classes such as environmental chemicals and additives sharing the same adverse outcome pathway. At the end of the project, EuroMix will deliver practical guidance on how to use the EuroMix models, tests and data in line with future needs of OECD, the World Health Organisation, the European Commission and EFSA.
Aggregated and cumulative risk assessment in the USA: CARES NG
Bruce Young from Bayer Crop Science in the US presented an overview on CARES NG (caresng.org) – a cloud-based, probabilistic model. CARES NG uses public data and is aimed at providing multi-route and multi-source aggregate and cumulative exposure to pesticides. Young sees many advantages of CARES NG model: user friendly interface, integrated consumption and monitoring data and temporary consumption patterns, which allows the estimation of short-term exposure (time weighted average). CARES NG is a not-for-profit initiative of a number of different stakeholders.
Revised IESTI equation
Another central conference topic was devoted to the question of what effects the revised International Estimated Short-Term Intake (IESTI) equation will have on European maximum residue levels (MRLs), and, accordingly, on consumer protection. Gaelle Vial of the French Agency for Food, Environmental and Occupational Health and Safety (ANSES) assumes that there would be very little change as a result as no raw commodity are particularly affected by the modifications.