The European Chemicals Agency (ECHA) recently submitted several draft guidance documents concerning nanomaterials to Partner Expert Groups (PEG) for consultation. Following consultation with PEGs, ECHA will consult its committees and/or Forum, where relevant. The final consultation will be with the European Commission (EC) and the relevant Competent Authorities. To ensure that the guidance updating process is transparent and open to participation by relevant partners, ECHA will publish drafts of the texts and feedback from the different consultation steps on its website. According to the website, feedback on ECHA guidance can be provided by any party by using the guidance feedback form.
ECHA submitted the following draft information requirements and chemical safety assessment (IR&CSA) appendices on recommendations for nanomaterials for environmental endpoints to a PEG for consultation:
- Appendix R7-1 Recommendations for nanomaterials applicable to Chapter R7a Endpoint specific guidance. This document was prepared by the ECHA Secretariat for the purpose of this consultation and includes only the parts open for the current consultation, i.e.:
- Update of section 2.1.1 on sample preparation to provide specific indications on the parameters for characterization, pre-requisites, and preparation as monitoring awaited for any nanomaterial;
- Update of section 2.2.1 on water solubility to include alternative guidelines that could be used for this endpoint and to flag the non-applicability for insolubility as a waiver for other endpoints;
- Update of section 2.2.2 on partition coefficient n-octanol/water to strengthen the message that guidelines recommended for this endpoint for non-nanomaterials are not applicable for nanomaterials and recommend other parameters that could be considered instead; and
- Update of section 2.2.4 on adsorption/desorption to clarify that the methods recommended in the parent guidance for this endpoint are not applicable for nanomaterials and recommend other parameters that could be considered instead.
- Appendix R7-1 Recommendations for nanomaterials applicable to Chapter R7b Endpoint specific guidance. The draft notes that the numbering of the sections has changed. It includes the following changes, and the following section numbers refer to the updated numbering of the guidance:
- New advisory note (section 1.1) on testing for ecotoxicity and fate to provide overall advice for conducting ecotoxicity and environmental fate testing for nanomaterials;
- Update of section 1.2.1 on aquatic pelagic toxicity to clarify that high insolubility cannot be used as a waiver and to include further recommendations on the text to be performed for this endpoint;
- Update of section 1.2.2. on toxicity for sediment organisms to provide advice on spiking methods and include applicability of available Organization for Economic Cooperation and Development (OECD) guidelines; and
- Update of section 1.2.3 on degradation/biodegradation to clarify that waivers for hydrolysis and degradation simulation testing are not applicable as sole evidence, and provide advice on photocatalytic degradation and general advice on performing the tests.
- Appendix R7-2 Recommendations for nanomaterials applicable to Chapter R7c Endpoint specific guidance. This document was prepared by the ECHA Secretariat for the purpose of this consultation and includes only the parts open for the current consultation, i.e.:
- Update of section 2.1.1. on aquatic bioaccumulation to explain the general limitations of the octanol-water partitioning coefficient (Kow) as the basis for a waiver for nanomaterials and provide advice on the applicability of the available OECD guidelines; and
- Update of section 2.1.2 on effects on terrestrial organisms to provide advice on spiking methods and use of different metrics.
A different PEG is reviewing Appendix 4: Recommendations for nanomaterials applicable to the Guidance on Registration. ECHA developed the draft Appendix to provide advice to registrants preparing their registration dossiers for nanomaterials. The aim of the Appendix is to define the term “nanoform,” the minimum criteria for distinguishing between different nanoforms, and the minimum set of parameters that must be reported to characterize a reported nanoform. According to the draft Appendix, a “nanoform” is a form of a substance that meets the requirements of the EC definition of a nanomaterial and always has a specific shape and a specific surface chemistry as additional parameters. The three minimum elements for defining a nanoform are: (1) whether it meets the EC recommendation on the definition of a nanomaterial; (2) its shape; and (3) its surface chemistry. ECHA notes that these are simply the minimum elements necessary to characterize registered nanoforms in a registration dossier. Depending on the substance, additional elements and/or additional refinement of these elements (i.e., specific size ranges, specific shapes, etc.) may need to be reported depending on their impact on properties as determined in the data collected/generated to fulfill information requirements. The draft Appendix states: “Where nanoforms are not reported transparently in the registration dossier for the substance, it is understood as an explicit statement made by the registrants of that substance that nanoforms are not within the scope of their registered substance.” The minimum parameters to be reported when nanoforms are registered are: (1) size; (2) shape; and (3) surface chemistry.
A PEG is consulting on Appendix R.6-1: Recommendations for nanomaterials applicable to the Guidance on QSARs and Grouping. ECHA intends the document to provide an approach on how to justify the use of hazard data between nanoforms of the same substance, and it is presented as an Appendix to Chapter R.6 of the Guidance on IR&CSA on quantitative structure-activity relationships (QSAR) and grouping “because general concepts on grouping of chemicals are applicable to [nanomaterials].”
A PEG is consulting on Appendix R7-1 Recommendations for nanomaterials applicable to Chapter R7a Endpoint specific guidance and Appendix R7-2 Recommendations for nanomaterials applicable to Chapter R7c Endpoint specific guidance. This document is a proposed amendment to specific extracts only of the following guidance documents: Appendix R7-1 to Chapter R.7a. (section 3 only); and Appendix R7-2 to Chapter R7c (section 2.1.3 only).