The REACH legislation requires industry to evaluate the toxicity not just of new chemicals, but also of the tens of thousands of existing chemical substances that are currently in use but have never been subject to regulatory testing. Many argue that to achieve this by traditional in vivo testing would take decades, cost billions and consume many millions of vertebrates. In addition to the time and costs for industry, there is a lack of laboratories in Europe capable of performing in vivo tests for such large numbers of substances.
The short questionnaire is our invitation to policy makers, industry managers, educators, political leaders, NGOs, investors, citizens and all others who are not specialists in toxicology to comment on some of the issues that are raised and/or addressed by computer-based (in silico) methods.
We really hope you can take a few minutes to complete it. Please also email the link to others who may be interested.
The CAESAR and VEGA platforms have been produced from EC-funded research, and are therefore freely available for use. The software can be downloaded. Furthermore, predicted values for more than four million chemicals will be made freely available.
ECHA does not intend to produce a list of ‘approved’ models, because the value of a model depends on how it is used. (See FAQ: ‘What makes a good QSAR model?’) Every user of QSARs needs to be aware that QSAR models are only appropriate and reliable for specific sets of chemicals. A highly reliable model will not produce reliable results for chemicals that lie outside the domain of applicability. In addition, models may be suitable for different regulatory functions: risk assessment, classification and labelling or prioritisation, because each makes different demands on the model.
QSARs have been used for decades in the development of pharmaceuticals, where a drug is to be developed to achieve a particular biological action. Our interest here is in the reverse use, where the chemical is known, and the biological action is to be predicted. That too has been the focus of research for decades. But here we are concerned specifically with their use for evaluating toxicity within the regulatory framework of REACH, and it is early days.
In practice, the use of in silico methods by European industry within REACH is still limited. There are three key practical issues that can delay their use. They are highly inter-connected.
REACH explicitly encourages innovation in toxicity evaluation. The development of alternative methods is one of the purposes of REACH.
The legislation sets out conditions specifically for the use of QSAR models, and the European Chemicals Agency (ECHA) offers detailed guidance. Even the introductory ‘Guidance in a nutshell’ on substance registration advises industry to ‘collect QSAR estimated results for the substance if suitable models are available’ as an initial step.
However, acceptability depends on both the model and on how it is used in practice. See ‘What makes a good QSAR model?’
Unlike industry working within a regulatory context, toxicology and ecotoxicology researchers have the freedom to select and/or develop QSAR models specifically for their scientific use, and do not need to meet the regulatory demands for transparency.
In silico methods, and specifically QSAR models, can be used in a range of ways within research. QSAR models provide statistical evidence of patterns of toxicity across a series of chemicals, and so, for example, can provide an agenda for empirical research into the mechanisms of action by which particular molecular properties generate those observed biological and environmental effects.
The REACH legislation puts the responsibility on industry to provide the necessary toxicity information on each substance which they manufacture, distribute and market, and to assess and manage the risks linked to those substances. This is the principle of ‘no data, no market’. Industry are therefore a key stakeholder in influencing the future use of in silico methods.
For further information, see the page ‘Why use in silico methods?’ on this site. It outlines why industry needs to use in silico methods, or at least know about them.