Priority Existing Chemical Assessment Reports -

Glycolic Acid

 

CHEMICAL IDENTITY

Chemical name

• Hydroxyethanoic acid

Other names

• Acetic acid,

• hydroxy-Alpha-hydroxyacetic acid

• Gluco-hydroxy-acidGlycollic acid (Approved Australian Name)

• Hydroxyacetic acid

• 2-Hydroxyacetic acid

Trade names of cosmetic raw materials

• Glycolic acid

• Glypure®

• α-HydroxyAcids 'AHA'

• Amidroxy Apple

• Amidroxy Sugar Cane

• Fruitlange

• Multifruit BSC

• NAB Apricot Extract

• Sugar Cane AHA

Molecular formula C₂H₄O₃

Chemical Abstracts Service (CAS) Number 79-14-1

EINECS Number 201-180-5

APPLICANTS

Advanced Skin Technology Pty Ltd 1606 High St Glen Iris VIC 3143	ICN Biomedicals Australasia 12/167 Prospect Hwy Seven Hills NSW 2147
Allergan Australia Pty Ltd 22 Rodborough Rd Frenchs Forest NSW 2086	Internatio-Müller Australia/New Zealand Pty Ltd 64 Trenerry Cr Abbotsford VIC 3067
Amway of Australia 46 Carrington Rd Castle Hill NSW 2154	International Beauty Supplies Pty Ltd 6 Narrabang Way Belrose NSW 2085
Beiersdorf Australia Ltd 4 Khartoum Rd North Ryde NSW 2113	Johnson & Johnson Pacific Pty Ltd Stephen Rd Botany NSW 2019
Bio Scientific Pty Ltd 28 Munroe Ave Kirrawee NSW 2232	Kandas International Australia Pty Ltd Level 2, 762 George Street Haymarket NSW 2000
Bioscor International Pty Ltd 184 Huntingdale Rd Oakleigh East VIC 3166	Lever J H & Co Pty Ltd 6 Bond St Richmond SA 5033
Bronson & Jacobs Pty Ltd Parkview Drv Australia Cntr Homebush NSW 2140	Lever Rexona 219 North Rocks Rd North Rocks NSW 2151
Clariant (Australia) Pty Ltd 675 Warrigal Rd Chadstone VIC 3148	3M Australia Pty Ltd 950 Pacific Hwy Pymble NSW 2073
Clinical Skincare & Equipment Pty Ltd PO Box 649 Alderley QLD 4051	Merck Pty Ltd 207 Colchester Rd Kilsyth VIC 3137
Cosmetic Products Pty Ltd 1 Wella Way Sommersby NSW 2250	Montcove Pty Ltd 101 Allambi Ave Florida Gardens QLD 4218
Crampton RVB 29 Antlia St Regents Park QLD 4118	Nutri-Metics International (Australia) Pty Ltd 102 Elliott St Balmain NSW 2041
Crown Scientific Pty Ltd 144 Moorebank Ave Moorebank NSW 2170	Salon Marketing Services Pty Ltd Unit 6/165 Rookwood Rd Bankstown NSW 2200
Cussons Pty Ltd 282 Hammond Rd Dandenong VIC 3175	Sanofi Beaute Australia Pty Ltd 166 Epping Rd Lane Cove NSW 2066
Doctors Formula Pty Ltd 1/182 Euston Rd Alexandria NSW 2015	Scental Pacific Pty Ltd 53 Jersey Rd Bayswater VIC 3153
Du Pont (Australia) Ltd 168 Walker St North Sydney NSW 2060	Sigma Aldrich Pty Ltd 14 Anella Ave Castle Hill NSW 2154
Eckstein Australia Pty Ltd 66c Maryborough St Fyshwick ACT 2609	Specialty Supply Australia Pty Ltd 9/10-12 Yalgar Rd Kirrawee NSW 2232
Goldwell Cosmetics (Australia) Pty Ltd 103 Yerrick Rd Lakemba NSW 2195	Universal Aesthetics Pty Ltd 1/14 Roseberry St Balgowlah NSW 2093
Hamilton Laboratories 217 Flinders St Adelaide SA 5000	Victor Paul Direct Marketing Pty Ltd 561 Botany Rd Waterloo NSW 2017
Heavenly Beauty 12/300B Burns Bay Rd Lane Cove NSW 2066	Yves Rocher 46 South St Rydalmere NSW 2116

OVERVIEW OF GLYCOLIC ACID ASSESSMENT

Glycolic acid (CAS No. 79-14-1) was declared a Priority Existing Chemical for preliminary assessment on 7 April 1998. The reason for the declaration was concern about the health effects of the chemical following consumer complaints that some cosmetic products containing glycolic acid caused irritation of the skin. The declaration applied to cosmetic uses of the chemical.

Glycolic acid is prepared by chemical synthesis or extraction from plants and has both industrial and domestic applications that utilise its acidity and ability to dissolve encrustations.

In Australia, annual imports for cosmetic purposes amount to 5.7 metric tonnes per year, of which about 2/3 is imported in finished cosmetic products and the remainder as raw materials used by local formulators. Cosmetic grade raw materials include crystalline glycolic acid, 70% aqueous solutions and plant extracts containing 2.5-17% glycolic acid. An industry survey identified 180 cosmetic products on the Australian market that contain glycolic acid, of which 25 are used in beauty salons and 155 are sold to consumers for use at home. Apart from 11 consumer hair care products, all products are intended for application to the skin. Salon products contain from 4-60% glycolic acid at pH 1.5-4.5. Consumer products contain 0.01-20% glycolic acid at pH 3.0-6.6.

Glycolic acid is absorbed by ingestion, inhalation and through the skin. In humans, it is mainly excreted unchanged in the urine while smaller amounts are metabolised to glyoxylic and oxalic acids, which are also excreted in the urine. The kinetics and metabolism are qualitatively similar in rats and humans; however, rats metabolise a greater proportion to carbon dioxide and eliminate the chemical faster than humans.

In laboratory animals, glycolic acid is harmful by single-dose ingestion or inhalation of high doses. Depending on concentration and pH, it may be corrosive or irritating to the skin, eyes and respiratory system. It is toxic to the kidneys by repeated oral administration. When glycolic acid is given to pregnant rats by mouth on a daily basis, it induces malformations at high, maternally toxic doses. In two studies, there was an 8-9% reduction in foetal body weight and a substantial increase in minor skeletal abnormalities at dose levels associated with mild maternal toxicity. In another study, a marginal increase in foetal abnormalities was seen at a dose associated with marginal maternal toxicity, with no effects on foetal development seen at lower doses. Glycolic acid is not mutagenic. It does not impair fertility or neonatal growth during lactation. There are no animal studies of systemic or developmental toxicity from dermal exposure and no carcinogenicity studies.

Glycolic acid is a metabolite of ethylene glycol and is the immediate cause of the metabolic acidosis and kidney failure associated with ethylene glycol poisoning in humans. Cosmetic formulations with glycolic acid have been extensively tested in human tolerability studies. There is no evidence of contact sensitisation; however, glycolic acid causes stinging and skin irritation in a dose- and/or pH-dependent manner. In use studies of products with 0.5-50% glycolic acid at pH 1.2-5.5, 13% of subjects had signs of skin irritation and 10% complained of stinging. In one study glycolic acid increased the sensitivity of human skin to sunburn by up to 50% in some individuals.

Occupational exposure to glycolic acid in the cosmetic industry is predominantly through skin contact as the chemical is practically non-volatile and the formation of aerosols (mists) is likely to be insignificant during formulation and beauty salon use of cosmetic products. Occupational control measures such as isolation, engineering controls and/or the use of personal protective equipment are in place in most formulation plants. Control measures in beauty salons include the substitution of solutions with gels or creams to minimise dispersion and the use of gloves to reduce hand exposure. Current MSDS and labels are satisfactory for synthetic raw materials. In the case of plant extracts and salon-only products, MSDS and labels generally do not comply with the ASCC National Model Regulations for the Control of Workplace Hazardous Substances.

The public is exposed to skin contact with a variety of cosmetic products that contain the chemical. Under the Trade Practices (Consumer Product Information Standards) (Cosmetics) Regulations, consumer cosmetics must be labelled with their ingredients. Ten of 66 labels assessed (15%) did not comply with the ingredient labelling requirements and 18 (27%) did not explicitly disclose the presence of glycolic acid in the formulation.

The no observed adverse effect level (NOAEL) based on a 3-month oral rat toxicity test and on maternal and developmental toxicity in pregnant rats is 150 mg/kg/day.

External exposures obtained from reasonable worst-case workplace scenarios are estimated at 1.7 mg/kg/day in beauty salon workers and 6.3 mg/kg/day in formulation workers. As such, the known uses of glycolic acid in the cosmetic formulation and beauty salon industries are considered unlikely to present a significant risk to occupational health in Australia if exposure is appropriately controlled.

External exposures obtained from reasonable worst-case consumer scenarios are estimated at 10 mg/kg/treatment for skin peels of large areas of the body and at 28 mg/kg/day from at-home use of glycolic acid cosmetics. Based on the same scenarios, the estimated internal exposure level is 4.7 mg/kg/day on the day of a salon treatment and 3.4 mg/kg/day for use at home. Compared with the NOAEL determined in rats, this represents a margin of exposure below the recommended level for chemicals which are widely used by the general population. However, considerations relating to the route and frequency of exposure, the blood levels known to be associated with systemic toxicity in humans and the pH of commercial formulations relative to the test materials used in animal studies justify the conclusion that the use of glycolic acid in salon and consumer cosmetics is unlikely to pose a significant risk to the general public, although skin and eye irritation may occur at high concentrations and low pH values.

Based on the assessment findings and the ASCC Approved Criteria for Classifying Workplace Hazardous Substances, it is recommended that glycolic acid for use at work be classified as 'Harmful by inhalation and if swallowed' (Risk phrase R20/22), 'Causes burns' (R34), 'Risk of serious damage to eyes' (R41), 'Irritating to eye and skin' (R36/38), and 'Irritating to respiratory system' (R37).

It is recommended that glycolic acid be included in the ASCC List of Designated Hazardous Substances with the above classification. The reference cut-off levels for mixtures are in section 15.1 of the main report.

Suppliers of the chemical for workplace use should update their MSDS and labels in accordance with the recommended hazard classification. As with other hazardous workplace chemicals, employers should conduct a risk assessment of their individual workplace and, where necessary, implement appropriate control measures.

Glycolic acid in cosmetic products used by the general public may cause skin and eye irritation when present at high concentrations and low pH values. As such, it is recommended that glycolic acid be considered for listing in the Standard for the Uniform Scheduling of Drugs and Poisons. In addition, manufacturers, importers and suppliers of consumer products should inform consumers that the use of skin exfoliant cosmetic products may result in an enhanced sensitivity to sunburn, and that use of sunscreen protection is advised.

On the basis of the assessed hazard, exposure information and current controls, NICNAS does not recommend a full (risk) assessment of glycolic acid in cosmetic products at this time.