What does this mean for a Notification?

Default data

Schedule data requirements

The normal set of Schedule Data Requirements for the notification category will be required for the chemical itself.

  • The repeated dose study where required by the Schedule must address data on hepatotoxicity since the liver is the target organ for most perfluorinated compounds.
  • The requirement for information on impurities and/or residual monomers is important for these chemicals and polymers, and analytical reports must be provided.
  • Impurities and residual monomers containing perfluorinated chains will need to be characterised at ≥0.01%, except where the chemical or polymer is proposed to be used in a food contact application, in which case these impurities should be characterised at ≥1 ppm, due to the possibility of migration of the impurities into food.

Additional requirements beyond the Schedule may be requested by us where the chemical itself is predicted to be highly persistent, or to produce persistent breakdown products other than those discussed below. These are addressed in later Sections of this section.

Degradation products

The perfluorinated sections of chemicals or polymers containing perfluorinated carbon chains are resistant to degradation. By the combined effects of hydrolysis and biodegradation, the perfluorinated chains are considered to produce a group of simpler perfluorinated chemicals, including perfluoroalkyl sulfonates (PFAS) and perfluoroalkyl carboxylic acids (PFCAs). Even comparatively slow degradation will result in increasing concentrations of these chemicals in the environment, due to their persistence.

NICNAS will, as a default, assume that:

  • Perfluorinated chains terminated with a sulfonyl group (eg sulfonamide) will degrade to PFAS of the same chain length.
  • Perfluorinated chains terminated with a hydrolysable group such as iodide or a silane will degrade to a PFCA containing one less perfluorinated carbon atom,
  • Perfluorinated chains terminated with an alkyl or aryl group will degrade to form a mix of PFCAs with both the original chain length and one less perfluorinated carbon atom.

We will use these assumptions for assessment purposes except where the notifier can provide experimental information to indicate that these are not relevant.

Toxicity information on degradation products

Toxicity information relating to a limited set of degradation products is currently available to NICNAS.

Default data sources may be subject to change as new toxicity data becomes available to NICNAS.

For degradation products other than those listed above, the PFOA hazard information will be used to estimate the hazard for PFCAs. For PFAS degradation products apart from PFBS, the PFOS hazard information will be used to estimate the hazard.

Notifiers should familiarise themselves with the relevant hazard information for the assumed breakdown products, as this will be used for assessment purposes except insofar as the notifier can provide experimental information to indicate that these are not relevant, as specified in Section B below.

The toxicity of impurities and residual monomers will also be considered using the default toxicity information unless additional relevant information is provided by the notifier.

Persistence and bioaccumulation characterisation

For perfluorooctane sulfonic acid (PFOS) and its derivatives, the OECD hazard assessment report [PDF] will be used as a default data source. For perfluorooctanoic acid (PFOA) and its derivatives, the US EPA preliminary risk assessment [PDF] will be used as a default source, while for perfluorobutane sulfonic acid (PFBS) and its derivatives, the NICNAS hazard assessment [PDF 1.8MB] will be used as a default source. Default data sources may be subject to change as new data becomes available to NICNAS.

For degradation products other than those listed above, the PFOA hazard information will be used to estimate the persistence and bioaccumulation for PFCAs, subject to the assumption that bioaccumulation will be greater for PFCAs of more than 8 carbon atoms. For PFAS degradation products apart from PFBS, the PFOS hazard information will be used to estimate the persistence and bioaccumulation, again subject to the assumption of greater bioaccumulation for PFAS of more than 8 carbon atoms.

Confidentiality

No claims of exempt information for the identities of the breakdown products will be accepted.

Assessment outcomes

Based on the hazard information for PFOA and PFOS, chemicals and polymers which produce PFCA and PFAS breakdown products apart from PFBS will be subject to the policy outlined in our PFOS alert Factsheet which sets out that these chemicals should be restricted to only essential uses, for which no suitable and less hazardous alternatives are available. Justification should be provided as to why a use should be considered essential and why no substitutes are available.

Lack of degradation of a polymer and/or lower toxicity than shown by the default data sets for the critical effects of hepatotoxicity, developmental toxicity and carcinogenicity must be demonstrated prior to a certificate being issued for uses which are outside this policy.

Provision of alternative data by notifier

Degradation products

In lieu of the default degradation assumptions, the notifier should provide information on the degradation pathways of the new chemical or polymer and the likely degradation products containing the perfluorinated carbon chain.  In doing this a higher-tiered test such as an inherent biodegradability test report is required, as there is a greater possibility of degradation occurring in the presence of other nutrients than under the conditions of a ready biodegradability test, where only the test substance is present.  This test should include characterisation of the degradation products and their rate of formation.

If the notifier claims that no degradation of the new chemical or polymer containing a perfluorinated carbon chain occurs, a report on analysis and characterisation of degradation products under relevant degradation conditions must be provided, as an inherent biodegradability test does not by itself give information on other degradation modes such as hydrolysis, or on formation of stable degradation products by a mechanism which does not involve mineralisation of a substantial proportion of the chemical or polymer, such as side chain cleavage.

If literature sources relating to surrogate data other than the default information used by NICNAS is provided, the notifier has to provide scientific justification on the applicability of the above studies to the notified chemical. NICNAS will determine if the surrogate data is applicable. An application for Variation of Schedule Requirements should be submitted under these circumstances.

Toxicological data

The repeated dose study needs to address data on hepatotoxicity since the liver is the target organ for most perfluorinated compounds.  In addition, the notifier is required to provide reproduction/developmental toxicity study and carcinogenicity studies for the degradation products, or for representative degradation products in the case where a number of different products are predicted.  The carcinogenicity test can be performed separately or combined with a chronic toxicity study.  All these tests should be performed according to the OECD Guidelines for Testing of Chemicals.  It is recognised that typically perfluorinated chemicals have not been reported to have genotoxicity potential and hence these tests are not required to be submitted. However, genotoxicity studies if available should be provided.

These data are required to be submitted for the chemical itself if this is predicted to be persistent, rather than being degraded or metabolised to PFAS or PFCA, or for persistent degradation products which are not in the PFAS or PFCA categories. The data requirements apply regardless of the notification category, except that these data are not required for the chemical itself in the case of notifications of polymers with Number Average Molecular Weight (NAMW) >1000.

If literature sources relating to surrogate data other than the default information used by NICNAS is provided, the notifier has to provide scientific justification on the applicability of the above studies to the notified chemical. NICNAS will determine if the surrogate data is applicable. An application for Variation of Schedule Requirements should be submitted under these circumstances.

Last update 7 February 2019