A substance of very high concern (SVHC) is a chemical substance (or part of a group of chemical substances) for which it has been proposed that the use within the European Union be subject to authorisation under the REACH Regulation. Indeed, listing of a substance as an SVHC by the European Chemicals Agency (ECHA) is the first step in the procedure for restriction of use of a chemical. The first list of SVHCs was published on 28 October 2008 and the list has been updated many times to include new candidates. The most recent update occurred on 17 January 2017 to include a total 173 SVHC.
The criteria are given in article 57 of the REACH Regulation. A substance may be proposed as an SVHC if it meets one or more of the following criteria:
The "equivalent concern" criterion is significant because it is this classification which allows substances which are, for example, neurotoxic, endocrine-disrupting or otherwise present an unanticipated environmental health risk to be regulated under REACH.
Simply because a substance meets one or more of the criteria does not necessarily mean that it will be proposed as an SVHC. Many such substances are already subject to restrictions on their use within the European Union, such as those in Annex XVII of the REACH Regulation. SVHCs are substances for which the current restrictions on use (where these exist) might be insufficient. There are three priority groups for assessment:
Proposals for inclusion of a substance on the list of SVHCs can come either from the European Commission or one of the Member States of the European Union. The proposals are made public by the European Chemicals Agency (ECHA) and are open for public comment for 60–90 days. If the substance is deemed to meet one or more of the criteria, it is then listed as an SVHC.
Once a substance has been listed as an SVHC, the Agency commissions a technical report from one or more national or private laboratories, which analyses the available information on manufacture, imports, uses and releases of the substance, as well as possible alternatives. On the basis of this technical report, the Agency decides whether to prioritise the substance, in effect, whether to make a recommendation to the European Commission to add the substance to Annex XIV of the REACH Regulation, making its use subject to authorisation. The draft recommendations must be made public and opened for comment for three months before the final recommendations are sent to the Commission. The first draft recommendations were published on 14 January 2009, and new draft recommendations must be issued at least once every two years.