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Scheduling delegate's final decisions, March 2016

Scheduling medicines and poisons

17 March 2016

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1.3 1-Naphthol

Part A - Final decisions on matters referred to an expert advisory committee

1. Scheduling proposals referred to the November 2015 meeting of the Advisory Committee on Chemicals Scheduling (ACCS#15)

1.3 1-Naphthol

Scheduling proposal

The chemicals scheduling delegate has referred the following scheduling proposal for consideration by the Advisory Committee on Chemicals Scheduling (ACCS):

  • To create a new entry for 1-naphthol in Schedule 6 to include use in hair dyes and eyelash colouring products with an appropriate cut-off.
Scheduling application

On the 28th August 2015, the National Industrial Chemicals Notification and Assessment Scheme (NICNAS), under its Inventory Multi-tiered Assessment and Prioritisation (IMAP) programme, referred the following proposal to be considered by the delegate for inclusion in the Poisons Standard:

The reasons for the request are:

  • the chemical has reported cosmetic use in permanent hair dye preparations in Australia;
  • the chemical is a strong skin sensitiser;
  • the chemical is a skin and eye irritant;
  • the chemical has moderate acute dermal toxicity;
  • only limited data are available on acute inhalation toxicity and no data on repeated dose inhalation toxicity; and
  • the overseas restrictions for use of this chemical in hair dyes state that the maximum concentration allowed in an oxidative hair dye substance is 1.0 % after mixing with hydrogen peroxide.
  • The critical health effect for risk characterisation is skin sensitisation. Given the potential for induction and elicitation of skin sensitisation even below the allowed overseas concentration cut-off, the risk would be better controlled by inclusion of warning statements on the label of preparations containing the chemical below the concentration cut-off. The chemical has similar use and hazard profiles to a number of chemicals which have been listed in Schedule 6 with reverse scheduling requirements.
Specific issues/questions raised by the delegate

The delegate asked the committee the following questions:

  • Does the ACCS agree that the toxicological profile of 1-napthalenol (acute toxicity, negative mutagenicity and sensitisation potential) warrants controls over use in cosmetics and consumer products?
  • What weight should be given to the evidence of severe skin sensitisation potential? Does the data suggest a suitable cut-off for the sensitisation potential?
  • Does the ACCS consider that including 1-naphthol in Schedules 6 is the best option for controlling its use in consumer products and cosmetics, including hair dyes and eyebrow/eyelash products? Should there be a cut-off to exempt at 2%, as suggested in the NICNAS report? Should this cut-off be adjusted to 1% when in combination with hydrogen peroxide?
  • If the ACCS recommends listing in Schedule 6, should exemptions apply when the product is labelled with appropriate warning statements, consistent with other oxidative hair dye ingredients with similar toxicological profiles?
  • Given that there may be some commercial uses other than in cosmetics, should a Schedule 6 listing be specific for use in hair dyes or cosmetic products (as for some other hair dye ingredients)?
  • What name should be used for any schedule entry - 1-naphthalenol or 1-napthol, alpha-naphthol or 1-hydroxynaphalene?
  • Is there a need for specific entries in Appendices E & F to manage labelling of scheduled products?
Substance summary

Please refer to the NICNAS Inventory Multi-tiered Assessment Prioritisation (IMAP) Human Health Tier II Assessment Report 1-naphthalenol and its related compounds. This report is publicly available on the NICNAS website.

Acute toxicity

The acute toxicity end-points for this chemical are listed in the below table.

Toxicity Species 1-naphthol SPF* Classification
Acute oral toxicity LD50 (mg/kg bw) Rat 1870 Schedule 6
Acute dermal toxicity LD50 (mg/kg bw) Rabbit 880 Schedule 6
Acute inhalational toxicity LC50 (mg/m3/4h) Rat >0.097 (limited data) N/A
Skin irritation Rabbit Irritant Schedule 5
Eye irritation Rabbit Severe irritant Schedule 6
Skin sensitisation (LLNA) Mouse Skin sensitiser (EC3 = 1.3 %) Schedule 6

*Scheduling Policy Framework for Medicines and Chemicals (SPF, 2015)

Skin sensitisation

Based on the available data, the chemical is a strong skin sensitiser.

In a local lymph node assay (LNNA) conducted according to the Organisation for Economic Co-operation and Development Test Guideline (OECD TG) 429, the chemical at 0.1, 0.25, 0.5, 1 or 2.5 % was applied topically to the ventral and dorsal surfaces of the ears of 18 female CBA/J mice. The mean stimulation indices were 1.4, 1.0, 1.2, 1.5 and 8.5, respectively, for the 0.1, 0.25, 0.5, 1 and 2.5 % concentrations. The effective concentration needed to produce a three-fold increase in lymphocyte proliferation (EC3) was calculated to be 1.3 %, indicating a strong sensitisation potential.

In a guinea pig maximisation test, both intradermal and topical induction used 0.1 % aqueous solutions of the chemical. Two weeks after topical induction, the animals were challenged by an occlusive dermal application of 0.05 % or 0.1 % of the chemical for 24 hours. No skin reaction was observed in this study. However, it should be noted that the concentration of the chemical used in this study was considered to be too low to clearly characterise the sensitisation potential of the chemical.

In an open epicutaneous test, a 3 % dilution of the chemical was applied onto the shaved flank skin of Pirbright white guinea pigs for six days/week for three weeks. Two weeks later a single challenge dose was applied to the opposite flank skin. No skin reaction was observed in the animal.

Repeat-dose toxicity

Based on the available data, the chemical is not expected to cause serious damage to health from repeated oral and dermal exposure. No information was available on repeated dose inhalation toxicity.

Genotoxicity

Based on the available data from in vitro and in vivo genotoxicity studies, the chemical is not considered to be genotoxic.

Carcinogenicity

Limited data are available. The chemical at 0.5 % concentration was not carcinogenic.

Reproduction and developmental toxicity

Based on the available data, the chemical is not expected to cause reproductive and developmental toxicity.

Public exposure

The chemical is reported to be used in permanent hair dye preparations in Australia. Internationally, the chemical is used in oxidative hair dyes.

The Association of South East Asian Nations (ASEAN), Canada, New Zealand and the European Union (EU) have restricted the use of this chemical in cosmetics. Following a safety evaluation, the Scientific Committee on Consumer Products concluded that 'apart from the risks associated with the use of a strong sensitiser, the use of the chemical itself in oxidative hair dye formulations at a maximum concentration of 2.0 % on the head, does not pose any other risk to the health of the consumer'.

Currently, there are no restrictions in Australia on using this chemical in cosmetic products. In the absence of any regulatory controls, the characterised critical health effects (particularly skin sensitisation) have the potential to pose an unreasonable risk to the public given the identified uses.

International regulations

The chemical is listed on the following:

  • ASEAN Cosmetic Directive Annex III - Part 1: List of substances which cosmetic products must not contain except subject to restrictions and conditions laid down: 'after mixing under oxidative conditions the maximum concentration applied to hair must not exceed 2.0%';
  • EU Regulation (EC) No 344/2013 Annex III - List of substances which cosmetic products must not contain except subject to the restrictions laid down: 'after mixing under oxidative conditions the maximum concentration applied to hair must not exceed 1 % calculated as free base';
  • New Zealand Cosmetic Products Group Standard - Schedule 5: Components cosmetic products must not contain except subject to the restrictions and conditions laid down: '(a) the maximum authorised concentration in the finished cosmetic product is 2.0%; and (b) in combination with hydrogen peroxide the maximum use concentration upon application is 1.0%'; and
  • Health Canada List of prohibited and restricted cosmetic ingredients (The Cosmetic Ingredient 'Hotlist').

In the EU, it is mandated that products containing the chemical at any concentration have warning labels indicating that the product can be allergenic.

Scheduling status

N/A

Scheduling history

1-naphthol has not been previously considered for scheduling; therefore, scheduling history is not available.

Pre-meeting public submissions

One public submission was received. No objections to aligning with the EU requirements were raised. It was noted however that it is important to maintain "in-use" concentrations for hair dye preps, due to the mode of use being mixing with an oxidising substance prior to use.

The public submission is available at Public submissions on scheduling matters.

ACCS advice to the delegate

The Committee recommended that new Schedule 6, Appendix E and Appendix F entries be created for 1-naphthol with appropriate cut-offs and exemptions as follows:

Schedule 6 - New Entry

1-NAPHTHOL except in hair dye containing 1 per cent or less after mixing under oxidative conditions when the immediate container and primary pack are labelled with the following statements:

KEEP OUT OF REACH OF CHILDREN, and

WARNING - This product contains ingredients which may cause skin sensitisation to certain individuals. A preliminary test according to the accompanying directions should be made before use. This product must not be used for dyeing eyelashes or eyebrows; to do so may be injurious to the eye.

Written in letters not less than 1.5 mm in height.

Appendix E - New Entry

1-NAPHTHOL

Part 1: Standard Statements: A, E1, S1

Appendix F - New Entry

1-NAPHTHOL

Part 1: Warning Statement: 28

Part 2: Safety Directions: 1

The committee recommended an implementation date of 1 June 2016.

The matters under subsection 52E (1) of the Therapeutic Goods Act 1989 considered relevant by the Committee included: (b) the purposes for which a substance is to be used and the extent of use of a substance; and (c) the toxicity of a substance.

The reasons for the recommendations comprised the following:

  • The substance is used in hair dye products
  • The substance has acute oral and dermal toxicity and is a strong skin sensitiser, a skin irritant and moderate to severe eye irritant and meets the criteria for inclusion in Schedule 6
Delegate's considerations

The delegate considered the following in regards to this proposal:

  • Scheduling proposal;
  • Public submissions received;
  • ACCS advice;
  • Section 52E of the Therapeutic Goods Act 1989;
  • Scheduling factors3;
  • Other relevant information.
Delegate's interim decision

The delegate's interim decision is to create new Schedule 6, with appropriate exemption and cut-off, Appendix E and Appendix F entries for 1-naphthol.

Oxidative hair dyes of the aromatic diamine and aminophenolic classes have some common toxicological properties that warrant controls over scheduling. These features are primarily skin-eye irritancy and sensitization potential. These toxicological properties generally align with SPF criteria for listing in Schedule 6. Several of these dyes (e.g. phenylenediamines, toluenediamines; aminophenols) have already been listed in Schedule 6, but previous scheduling policies have allowed for some products to be exempted where there are label statements warning of the potential for skin irritancy and sensitization, and recommending testing for individual susceptibility before use. This approach is commonly called 'reverse scheduling'. Where there is potential mutagenicity, or the need to prevent uses for skin colouration (tattooing) or use to dye eyebrows or eyelashes, some of these substances have been listed in Schedule 10 to prevent such uses.

This is one of six oxidant hair dyes that were referred to the November 2015 meeting of the ACCS for advice to the delegate on scheduling. The key issues were whether their toxicological profiles sufficiently match the SPF criteria for inclusion in Schedule 6 and whether product exemptions based on 'reverse scheduling' could be applied, consistent with labelling provisions applied to other oxidative hair dyes. Given that some products containing oxidative hair dyes require mixing with an oxidant, such as hydrogen peroxide, before application to the hair, consideration was given to appropriate exemption cut-off concentrations that take account of the final concentration applied to the hair.

The delegate notes, and accepts, ACCS advice that 1-napthol should be listed in Schedule 6, with an exemption cut-off at 1%, provided products are labelled with the warning statements about potential skin/eye irritation and sensitisation that have been required for similar oxidative hair dyes. The delegate also notes ACCS advice that the potential for severe eye irritation requires warning statements relating to use for dyeing eyebrows and eyelashes. The INCI name (1-naphthol) is the preferred name for listing in the Schedules.

The matters under subsection 52E (1) of the Therapeutic Goods Act 1989 considered relevant by the delegate included: b) the purposes for which a substance is to be used and the extent of use of a substance; c) the toxicity of the substance; d) the dosage, formulation, labelling, packaging and presentation of a substance.

Schedule entry
Schedule 6 - New Entry

1-NAPHTHOL except in hair dye preparations containing 1 per cent or less of 1-naphthol after mixing under oxidative conditions when the immediate container and primary pack are labelled with the following statements:

KEEP OUT OF REACH OF CHILDREN, and

WARNING - This product contains ingredients which may cause skin sensitisation to certain individuals. A preliminary test according to the accompanying directions should be made before use. This product must not be used for dyeing eyelashes or eyebrows; to do so may be injurious to the eye.

Written in letters not less than 1.5 mm in height.

Appendix E - New Entry

1-NAPHTHOL

Part 1: Standard Statements: A, E1, S1

Appendix F - New Entry

1-NAPHTHOL

Part 1: Warning Statement: 28

Part 2: Safety Directions: 1

Public submissions on the interim decision

One submission was received. The submission supported the delegate's interim decision.

Edited versions of public submissions are available at Public submissions on scheduling matters.

Delegate's final decision

The delegate notes the submission received in response to publication of the interim decision and confirms the interim decision as no evidence has been received to alter the interim decision. The delegate has confirmed that the reasons for the final decision are in keeping with those for the interim decision.

Schedule entry
Schedule 6 - New Entry

1-NAPHTHOL except in hair dye preparations containing 1 per cent or less of 1-naphthol after mixing under oxidative conditions when the immediate container and primary pack are labelled with the following statements:

KEEP OUT OF REACH OF CHILDREN, and

WARNING - This product contains ingredients which may cause skin sensitisation to certain individuals. A preliminary test according to the accompanying directions should be made before use. This product must not be used for dyeing eyelashes or eyebrows; to do so may be injurious to the eye.

Written in letters not less than 1.5 mm in height.

Appendix E - New Entry (Part 2)

1-NAPHTHOL

Standard Statements: A, E1, S1

Appendix F - New Entry (Part 3)

1-NAPHTHOL

Warning Statement: 28

Safety Directions: 1

The proposed implementation date is 1 October 2016.


Footnotes

  1. Scheduling Policy Framework for Medicines and Chemicals (SPF, 2015)

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