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Provisional Guidance on Use of Chemical Categories

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Provisional Guidance on Use of Chemical Categories Nickel compounds – a category approach for metals in EU legislation Jim Hart, Consultant prepared on behalf of the Danish Environmental Protection Agency January 2008 PREFACE: This report was commissioned by the Danish EPA, and describes the use of a categories approach to the classification and labelling of a group of nickel compounds. The Danish EPA is the Rapporteur for the risk assessment of nickel and four nickel compounds (nickel sulphate, nickel dichloride, nickel dinitrate and nickel carbonate) under the EU Existing Chemicals Regulation (EEC) 793/93. Part of this work included data collection and evaluation of a number of other nickel compounds such as the nickel oxides and sulphides. As a result of this work, classification and labelling proposals for the five nickel compounds evaluated under the EU Existing Chemicals Regulation have been prepared by the Danish EPA, and, after discussion in the EU Technical Committee for Classification and Labelling, new and revised entries for the five compounds have been included in Annex I to Directive 67/548/EEC (List of Dangerous Substances), which was adopted by a Technical Progress Committee in February 2007 as part of the 30th Adaptation to Technical Progress of the Directive (ECB, 2007a). In addition, proposals for updating the existing entries for some of the other nickel compounds in Annex I to Directive 67/548/EEC (nickel hydroxide, nickel oxides and nickel sulphides) were also prepared by the Danish EPA, and agreed by the EU Technical Committee for Classification and Labelling for inclusion in the 31st Adaptation to Technical Progress of the Directive. Based on the agreed classification for these individual substances, the Danish EPA then prepared a classification proposal covering more than 100 nickel compounds. This proposal reflected the group approach already used for a number of metals in Annex I, but refined the approach by proposing classifications based on a number of different subgroups. After discussion and further refinement, this proposal was also agreed by the EU Technical Committee for Classification and Labelling in 2006 for inclusion in the 31st Adaptation to Technical Progress of the Directive (ECB, 2007b). This report describes these proposals and the discussions in the EU Technical Committee. The experience of this discussion, and the relevance of the approach used here for a Category approach to metals has formed part of the development of guidance for the use of a Category approach in both the EU and the OECD. This report is an updated version of Example F in Chapter 3.2 “Guidance on the Development and Use of Chemical Categories in the HPV Chemicals Programme”, in the OECD “Manual For Investigation of HPV Chemicals”. This guidance document was prepared by the OECD Secretariat based on the agreements reached in the OECD Existing Chemicals Programme up to May 2005. The experience in the development of these proposals is also reflected in the EU Technical Guidance Document to Industry on the Information Requirements for REACH (RIP 3.3 project). This report reflects the status of the discussion of the classification and labelling of these nickel compounds at the time of publication in December 2007. The report reflects the proposals for the Annexes to the 31st ATP as shown on the ECB website. The subheadings used in this document reflect the stepwise procedure described in the OECD 2005 guidance, but do not necessarily reflect the stepwise approach proposed in the latest (2007) OECD or guidance or the draft RIP 3.3 guidance. 2 INDEX PREFACE:...................................................................................................................................................... 2 INTRODUCTION .......................................................................................................................................... 4 IDENTIFICATION OF STRUCTURE-BASED CATEGORY AND ITS MEMBERS:............................... 6 GATHER PUBLISHED AND UNPUBLISHED DATA FOR EACH CATEGORY MEMBER. ................ 8 EVALUATE DATA FOR ACCURACY. ...................................................................................................... 8 CONSTRUCT A MATRIX OF DATA AVAILABILITY............................................................................. 8 PERFORM AN INTERNAL ASSESSMENT OF THE CATEGORY. ....................................................... 10 THE NEED FOR FURTHER TESTING...................................................................................................... 17 FILL DATA GAPS BY READ-ACROSS, EXTRAPOLATION, INTERPOLATION ETC. ..................... 17 REFINEMENT OF THE CATEGORY........................................................................................................ 18 REFINEMENT OF THE READ-ACROSS.................................................................................................. 23 ADVICE WHEN READ-ACROSS IS NOT NECESSARILY APPLICABLE........................................... 29 CONCLUSIONS........................................................................................................................................... 31 REFERENCES ............................................................................................................................................. 32 TABLE 1: INVENTORY OF NICKEL COMPOUNDS.............................................................................. 36 TABLE 1.1: Nickel and Nickel Compounds in Einecs............................................................................. 36 TABLE 1.2: Nickel compounds included in Elincs. ................................................................................. 48 TABLE 1.3: Additional Nickel compounds, and complex substances containing nickel included in TSCA (through 08/2000) but not included in Einecs. .......................................................................................... 49 TABLE 1.4: Additional Nickel compounds listed in ECICS (European Customs Inventory of chemical substances), but not included in Einecs or the TSCA Inventory............................................................... 51 TABLE 1.5: Additional Nickel compounds in Annex I to Directive 67/548/EEC but not in Einecs or TSCA. ................................................................................................................................................................... 51 TABLE 1.6: Additional nickel compound found in the course of compiling the inventory of nickel compounds. ............................................................................................................................................... 51 TABLE 1.7: Additional nickel hydroxycarbonate compounds not included in the lists above. ............... 52 TABLE 1.8: Nickel containing minerals (from IARC, 1990 and NiPERA, 1996)................................... 52 3 INTRODUCTION 1. A category approach for compounds of concern is widely used in Annex I to Directive 67/548/EEC. Annex I is a list of dangerous substances with a harmonised classification and labelling agreed by the Members States according to the classification criteria adopted by formal EU legislative procedures. A list of the nearly 100 group entries already included in Annex I is given in the RIP 3.3. scoping study in the TAPIR final report Appendix 9. These entries are called “group” entries, and the term “category” is not used in the EU legislation. 2. Many of these group entries date from very early versions of Annex I and reflect the general concern for metal compounds, irrespective of the precise chemical composition of the actual compound. The concern for the hazard of these metal compounds is also reflected in the often very low concentration limits for certain metals to be considered as “Toxic” or “Harmful” included in the Paints and Varnishes Directive (EEC, 1977). These specific concentration limits were carried over into Annex I of Directive 67/548/EEC in the 12th ATP (EEC, 1991) with the introduction of the Preparations Directive in 1988 (EEC, 1988). Many of these limits still apply today. 3. Some of the entries are defined in quite general terms, such as “arsenic acid and its salts”. Other entries are equally general, but do make some exceptions to the general entry. An example is “antimony compounds, with the exception of the tetroxide (Sb2O4), pentoxide (Sb2O5), trisulfide (Sb2S3), pentasulfide (Sb2S5) and those specified elsewhere in this Annex”. The wording indicates that whilst the entry is considered generally applicable, certain compounds (in this case the oxides and sulfides) are excluded. Other entries are more specific. “Triethyltin compounds, with the exception of those specified elsewhere in this Annex” is a narrowly defined group of compounds. Finally, the elemental metal may be included as a separate entry. 4. Prior to the establishment of Einecs and other inventories of chemicals on the market, it was often impossible to develop comprehensive lists of the compounds covered by these group entries. In some cases (e.g. the proposals for a group entry for inorganic nickel compounds proposed by Norway and for chrom(VI) compounds proposed by Germany) the proposals were accompanied by a list of the compounds that were intended to be covered by the group entry. Now, increasing ease of carrying out computerised searches has made it possible to list the specific individual compounds included in these group entries. One source of this information is the N-Class database developed by Sweden and accessed from the ECB Classification
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