Quantitative Computer Models Can be Used to Evaluate Toxicity of Chemicals

An estimated 30 000 chemicals in use in the EU have not been tested. Concerned scientists have brought together necessary data, analysis tools and training materials to help toxicologists remedy the situation.

The EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulation now requires all chemicals to be evaluated and registered. Although the task is huge, data and analytical capability do exist.

Computer-based (in silico) methods for analysis of very large amounts of data have now made it possible to predict the physical, environmental and toxicological properties of chemicals from their molecular structures. In order to develop strategies for effective dissemination and use of such tools, scientists initiated the EU-funded 'Orchestra' project.

The scientists explain that "classical methods are based on structure–activity relationships (SARs) using a manual process of deriving relationships between molecular structures and specific toxicity effects (endpoints). Quantitative SAR (QSAR) models utilise the power of computers to model this relationship mathematically, enabling the evaluation of thousands of chemicals a day. The new QSAR platform known as VEGA is the focus of Orchestra dissemination activities.

A four-part video documentary titled 'QSAR in REACH: Uses, issues and priorities' was created from 20 interviews with key regulators, industry representatives and expert QSAR developers. Training materials for a 15-session course have also been developed for graduate and post-doctoral students."

The Scientists organizing the project also held a one-day workshop to spur interaction among industry, regulators and software developers regarding the regulatory use of QSAR methods. They presented QSAR methods at the SETAC (Society of Environmental Toxicology and Chemistry) conference after findings that most professional toxicologists knew little about QSARs.

Software products and databases can be found on the website of the Orchestra project, which also includes links to other initiatives such as those focused on regulation. All explanatory information, resources (including videos and training materials), and results of surveys are included. Orchestra is making it possible to exploit the huge human potential of multidisciplinary fields in the effort to register all chemicals in use by providing stakeholders with easy access to the data and analysis tools of which they may previously have been unaware.