Sodium dichromate authorisation for SDAC REF: 804

RPA was contracted by a consortium of nine companies to co-ordinate the preparation of an application for the authorisation of the continued use of sodium dichromate (EC No.: 234-190-3, CAS No.: 7789-12-0, 10588-01-9) in the manufacture of sodium chlorate in several plants located in Finland, France, Italy, Portugal, Spain and Sweden.  For this project, RPA’s long-term partner on REACH Authorisation matters, Forschungs- und Beratungsinstitut Gefahrstoffe GmbH (FoBiG), was sub-contracted for the preparation of the Chemical Safety Report (CSR).  The consortium of applicants was managed by ReachCentrum with which RPA and FoBiG collaborated closely for the duration of the project.

According to its harmonised classification and labelling, sodium dichromate may cause genetic defects, may cause cancer, may damage fertility and may damage the unborn child and was therefore added to the Annex XIV Authorisation list of the REACH Regulation (Regulation (EC) No 1907/2006) with a sunset date of 21 September 2017.  This meant that users of the substance in the EU should have submitted an application for the authorisation of their uses to ECHA by 21 March 2016.

Sodium dichromate is used as a processing aid in the manufacture of sodium chlorate from sodium chloride by electrolysis while hydrogen evolves as a co-product.  Sodium dichromate acts to increase the current efficiency by suppressing parasitic cathodic reactions and thus to avoid cathodic reduction of hypochlorite and chlorate.  It also has a number of other beneficial roles: it acts as a pH buffer; it suppresses the production of oxygen, thus preventing the creation of explosive mixtures with hydrogen; it passivates the steel cathodes, thus protecting them from corrosion; and it also promotes energy efficiency of the chlorate process.  In turn, sodium chlorate is an intermediate that is primarily used in the pulp and paper production where it is converted into chlorine dioxide, which in turn is used as a bleaching agent.

RPA was responsible for developing the analysis of possible alternatives, which demonstrated that there were no technically and economically feasible substitutes for sodium dichromate in the manufacturing process used by all of the applicant companies and which is the only commercially available method across the globe.  In addition, starting from the assessment of the cancer risks from the continued use of sodium dichromate which was generated by FoBiG, RPA quantified and monetised the human health cost of the continued use of the substance (in terms of statistical cases of cancer occurring) and compared this to the economic and social costs that would arise if the continued use of sodium dichromate was not authorised.  This analysis was presented in a separate document, the socio-economic assessment.  Due to the confidential natural of the socio-economic aspects of sodium chlorate manufacture, each applicant submitted their own separate application to ECHA.

The applications submitted by all applicants received favourable opinions from ECHA’s Risk Assessment (RAC) and Socio-Economic Assessment (SEAC) Committees which recommended a 12-year review period for the continued use of substance by all applicants, the maximum length that the Committees are able to recommend at present.  As of 30 August 2017, the European Commission had agreed to adopt the opinion of the two ECHA Committees for five of the nine companies and granted Caffaro Brescia S.r.l, Electroquímica de Hernani, S.A., Ercros SA, Kemira Chemicals Oy and Solvay Portugal – Produtos Quimicos S.A. an Authorisation for 12 years under Decisions which was published in the Official Journal on 14 June 2017.  The official publication of the Commission’s decisions for a further four companies (Arkema France, Akzo Nobel Pulp and Performance Chemicals AB, Akzo Nobel Pulp and Performance Chemicals Oy and Akzo Nobel Pulp and Performance Chemicals S.A.S.) is pending.  This positive result allows the continuation of the applicants’ business operations and supports the companies in their ongoing efforts to develop and switch to a feasible and safer alternative.