The REACH main objective is to improve the protection of human health and the environment from the risks that can be posed by chemicals

Models For REACH

The European legislation for chemical substances, REACH (Registration, Evaluation and Authorisation of Chemicals - Regulation (EC) No 1907/2006, in effect from 1 June 2007) is the most complex legislation produced in Europe, and certainly is more complex than any related legislation for chemicals in other non European countries. REACH promotes a new vision for handling chemical substances that requires a series of information submissions from the manufacturers and/or importers. The main objective is to improve the protection of human health and the environment from the risks that can be posed by chemicals. It requires all manufacturers and importers of chemicals to evaluate, identify and manage the risks linked to the substances they manufacture and market. In principle REACH applies to all chemicals, both new and existing, industrial and domestic.

REACH promotes innovation in the evaluation of chemical substances (Article 1) and foresees the use of non-animal alternative methods. The use of computational methods to calculate properties of chemicals is specifically identified, and Annex XI defines criteria for (quantitative) structure-activity relationship models:

“The use of a QSAR model is valid if:

• the model is recognised as scientifically valid (using the OECD principles);
• the evaluated substance is included in the applicability domain of the model;
• results are adequate for classification and labelling and/or for risk assessment;
• adequate documentation of the methods is provided.”

In other words, the use of QSAR models should be evaluated in terms of (i) the scientific quality of the model and the reliability of the data it is based on, (ii) whether the use of the model is appropriate for the particular target compound being evaluated, (iii) whether the model provides the full information required by REACH, and (iv) whether the documentation both of the model, and of its use in this case, is sufficient to enable a rigorous and independent review by the regulator.

Within REACH, in silico models can be used for three purposes:

1. Risk assessment
2. Classification
3. Prioritization

Different endpoints have to be addressed depending on the purpose and on the tonnage.

A survey of user needs and the barriers to the use of QSAR models for the different stakeholders has been carried out within the ORCHESTRA project, using questionnaires, meetings and interviews.

Respondents have identified a clear need for more details about QSAR models, including information about the meaning of the outputs from the models, the applicability domains of models, and the source data and other information that the models are based on.

The intention of VEGA is therefore to fill these information gaps, by offering tools to examine the results, their meaning, and the possible uses of the models. The VEGA tools have been developed in collaboration with a number of EC projects.