Safety Tests in Cosmetics

Panida Vayumhasuwan, Ph.D.Pan Rajdhevee Group Public

Co. Ltd.

Safety Tests in Cosmetics

A cosmetic product put on the market within the Community must not cause damage to human health when applied under normal or reasonably foreseeable conditions of use.

Safety Tests in Cosmetics

Several mechanisms have been developed regarding consumer health protection:

• List of chemicals which must not be contained.

• List of substances which cosmetic products must not contain except under restrictions.

• List of authorized substances, which may include coloring agents, preservatives and ultraviolet filters.

GUIDELINES

Safety Tests in Cosmetics

INGREDIENTS

FINISHED COSMETIC PRODUCTS

Safety Assessment of Cosmetic Ingredients

–Acute toxicity–Skin absorption–Skin irritation–Mucous membrane irritation–Skin sensitisation–Subchronic toxicity–Phototoxicity and photomutagenicity (in case of UV-light absorbing

substances

Safety Assessment of Cosmetic Ingredients

• Mutagenicity• Human data (if available)• Toxicokinetics• Teratogenicity, reproduction

toxicity, carcinogenicity, additional genotoxicity

• Metabolism studies

Material Safety Data Sheets (MSDS)

MSDS is a form containing data regarding the properties of a particular substance.

Product stewarding and workplace safety: provide workers and emergency personnel with procedures for handling or working with that substance in a safe manner.

Material Safety Data Sheets (MSDS)

1. Chemical product and company identification

2. Composition/information on ingredients :CAS number, conc., etc.

3. Hazards identification4. First aid measures5. Fire fighting measures6. Accidental release measures7. Handling and storage8. Exposure controls/personal protection

9. Physical and chemical properties – form, color, odor, boiling point, flash point, vapor pressure, density, solubility, pH, viscosity, etc.

10. Stability and reactivity

12. Ecological information – biodegradable, pollution, etc.

13. Disposal considerations14. Transport information15. Regulatory information16. Other information

Material Safety Data Sheets (MSDS)

11. Toxicological information

Safety Assessment (Finished Cosmetic Products)

Compatibility test: a test intended to confirm that there are no harmful effects when applying a cosmetic product for the first time to the human skin or mucous membrane.

Safety Assessment(Finished Cosmetic Products)

The assessment of the safety of cosmetic products depends on how it is used since it determines the amount of substance that may be ingested, inhaled or absorbed.

Therefore the safety evaluation has to be done on a case by case basis.

Skin Compatibility Assessment of Finished Cosmetic Products

Possible adverse reactions:

photomediated reactions, acne, contact urticaria,

pigment changes, hair and nail changes, etc.

skin irritation / skin sensitisation

Test protocol design depends on the specific question asked.

Factors affecting the safety evaluation

• Dosage form• Method of application: rubbed on,

sprayed, applied, etc.• Concentration of ingredients• Quantity of product used at each

application• Frequency of application• Total area of skin contact

Factors affecting the safety evaluation

• Site of application• Duration of contact• Quantity likely to enter the body• Application on skin areas exposed to

sunlight

Subject: age, skin type, skin condition, etc.

Frequently Used Test Designs

• Open / Closed patch tests• Single / Repeated exposure test

Single Application Open Epicutaneous Test

• Novel formulations that are to be used for the first time on human skin

• High-irritant potential formulations, e.g., depilatory, hair waving, hair coloring

Single Application Open Epicutaneous Test

Apply undiluted, usually to the arm, for exposure periods of up to 60 minutes (or at any time in case of adverse effects).

Evaluate visually: redness, scaling during and following the exposure

period.

Repeated Application Open Epicutaneous Test

• Decision is based on the results of a single open application test.

• The frequency of repeat applications will be decided on a case-by-case basis.

• Usually performed on an area of very sensitive skin, e.g., forearm area .

• Comparative assessment: same individual under standardized test conditions (exposure time, frequency, amount, concentration, sample temperature)

Repeated Application Open Epicutaneous Test

Evaluation:• Visual evaluation: scoring – redness, scaling,…• Objective evaluation: TEWL, redness intensity,

…

Single Application Closed Patch Epicutaneous Test

• For new or novel formulations with known raw materials

• For new formulations that have been shown to be safe to skin in an open patch test.

• Comparative assessment of several formulations on the same individual, generally including one or more REFERENCE preparations.

Single Application Closed Patch Epicutaneous Test

• The test products are applied diluted or undiluted to the skin (e.g., forearm, back) for periods up to 48 hours under occlusive or semi-occlusive patches.

• Evaluations are performed, e.g., 1, 24, 48 hours after removal of the patch.

Single Application Closed Patch Epicutaneous Test

Evaluation:• Visually: redness, scaling.• Objective measurements: TEWL,

redness intensity, etc.

Repeated Application Closed Patch Epicutaneous TestObjectives:• Optimization of formulations with

regarding to skin compatibility, especially for surfactant-containing products.

• Evaluation of small differences between formulations of zero to mild irritancy which are used frequently and/or repeatedly: toilet soaps/detergents, shampoos.

• Reference products can be included in the tests.

Repeated Application Closed Patch Epicutaneous Test

An example:The preparations (soaps, shampoos,…)

may be applied diluted on the forearm under occlusive or semi-occlusive patches, for example for 22 hours on the first day and 6 hours for each of the following 4 days.

The test can be stopped at any time if reactions occur.

Repeated Application Closed Patch Epicutaneous Test

Evaluations:Performed each day after patch removal

and before patch replacement.

Visually: redness, scaling,…Objective measurements: TEWL, redness,

…

Controlled Use Test

• Performed under normal or slightly exaggerated use conditions.

• Exposure/application conditions (which may vary widely for different product types) and evaluations are controlled and standardized.

(Uncontrolled) Use Test at Home

• Test under normal use conditions.• Participants may be selected to

represent different categories of consumer, e.g., of particular skin types.

• Large groups of volunteers and over a test period of a duration which is considered to be adequate to evaluate skin compatibility under normal, uncontrolled, use conditions at home, with periodic expert assessments of skin condition, and including comments by the volunteers on subjective effects.

• May be useful in assessment of product efficacy and acceptability

Subject Selection

• Number - enough to satisfy the test objective.

• Recruitment – inclusion / exclusion criteria.• Volunteers must be clearly informed,

verbally and in writing, regarding the nature of the study, timetable, constraints, possible risks.

• Give the written informed consent.

Inclusion Criteria

• Informed volunteers – appropriate of relevant age, sex, race, health condition.

• Panelists agreeing to follow the conditions specified in the study information sheet.

Non-Inclusion Criteria• Pregnancy or nursing condition.• Blemishes, marks (e.g. tattoos, scars,

sunburn) on the test sites(s), which would interfere with scoring.

• Medication that may affect skin response, or past medical history.

• Irritated skin on test site(s).• Any active skin disease that may interfere

with the study objectives.• Participation in another simultaneous

study.• Participation in a previous study without an

appropriate rest period between studies.

Withdrawal CriteriaParticipants will be withdrawn if:

• They do not follow the conditions of the study information sheet.

• They suffer any illness or accident or develop any condition during the study which could affect the outcome of the study.

• They no longer wish to participate in the study.

Test Sample(s)

• Reference samples – to check inter-/intra-laboratory variations, inter-seasonal variability.

• Concentration – adjusted/diluted according to the type of product, test protocol, study objective so as not to cause severe skin effects.

Product Application

• Skin areas with the likelihood of response variability should be avoided.

• Products will be randomized within and between subjects.

• In repeated patch studies, the patch site must be marked to ensure that successive patches are placed on exactly the same skin position.

Dose Level

• Patch tests - measured amount of test material.

• Use-related tests – quantity applied should be relevant to that expected to be used at home.

Removal of Test Sample

• When appropriate, test product(s) will be removed in the laboratory by a technician.

• Test sample(s) will be rinsed (or otherwise gently removed) from application sites without rubbing to avoid cross-contamination.

Assessments: Patch Tests

• Baseline: treatment sites are assessed before the first application.

• Treatment sites are assessed after treatment at times defined in the protocol.

• Must specify a period of time (e.g. 30 min) after patch removal before assessment.

• In case of unacceptable responses, the test sample(s) will not be reapplied on that participant any longer.

Assessments: Patch Tests

VISUAL ASSESSMENT of skin compatibility:

• scored by same experienced assessor who made the baseline assessment.

• Same lighting source.• Predefined scoring scale.

Assessments: Patch Tests

INSTRUMENTAL MEASUREMENT• Measured after an acclimatization period

in an environmentally conditioned room.• Instruments must be calibrated regularly

Data Interpretation

• Statistical analysis must be valid and specified in the protocol.

• Usually compare the new test product with those of positive and/or negative controls, or similar products with a substantial history of safety in the market.

Conclusion

Cosmetic ingredients: MSDS

Finished cosmetic products:Single application open epicutaneous test Repeated application open epicutaneous testSingle application closed patch epicutaneous

test Repeated application closed patch epicutaneous

test

in vitro Testing for Ocular Safety

• BCOP - Bovine Cornea Opacity and Permeability Test;

• FLT - Fluorescein Leakage Test;• HET-CAM - Hen’s Egg Test -

Chorioallantoic Membrane;• RBC - Red Blood Cell Test;• TEA - Tissue Equivalent Assay.