Download presentation
Presentation is loading. Please wait.
1
Toxicology in Cosmetics
Rupali N Madapura TY-Roll no: 35
2
Skin Sensitization An Allergic reaction to a particular irritant that results in the development of skin inflammation and itchiness.
3
Sensitization may be caused due to a variety of substances used in the manufacturing of cosmetics.
Some of these reactions are: Contact urticaria Photo toxicity Irritation Allergies
4
Inflammation may be due to prolonged use or appear immediately on usage.
Irritants: Substances that induce an inflammatory response. Primary irritants: immediate inflammation Secondary Irritants: Harmless on first contact. But induces irritation on prolonged use- increasing in severity with each subsequent use
5
Sensitivity Testing Sensitivity testing can be divided into two general categories: Diagnostic testing Prophetic or predictive testing
6
Diagnostic Test: The establishment of the cause of dermatitis produced by cosmetics in general.
Prophetic test: the ascertainment of the irritant and sensitizing power of the cosmetic
7
Draize test For detection of potential primary irritations.
Albino rabbits are clipped and the substance to be tested is applied to: intact skin, abraded skin, lightly scarified skin. All of them are covered with a patch for 24hrs.The sites of applications are examined at intervals & changes are recorded.
8
This method of testing can lead to false positive and false negative.
So its advisable to compare result of test substance with result of known harmless substance . Bureau of Indian standards recommends that if there is no reaction in any of animals, the same test should be performed on 10 human volunteers applying the substance on the skin of the forearm
9
Tests 1.Patch test - Open patch test - Prophetic patch test
2.Repeated insult test 3.Photo patch test 4.Test for sensitizing potential - Provocative patch test 5.Use test 6.Restricted consumer test
10
Patch Test Procedure gm of test sample is applied on a piece of cotton fabric and applied to the skin of arms, thighs or back. This patch is covered with patch of cellophane, sealed with adhesive plaster and allowed to remain on skin for hrs .
11
If there are no reactions ,the same patch may be made reapplied to the same place or fresh patch made or applied. This may be continued till either a reaction is produced under one or more patches or a qualified investigator confirms its safety. DESCRIPTION SYMBOL NO REACTION - ERYTHEMA ONLY + ERYTHEMA WITH PAPULES ++ PAPILOVASICULAR +++
12
Patch test- Open In case of cosmetics containing higher % of potential irritant like hair dyes, shampoos, hair tonics, patches should not be sealed. Open patch is performed on sensitive part of skin like bend of elbow, skin behind the ears.
13
Cosmetic to be applied to an area of 1 sq. m. of the skin. (+control)
Inspection 24 hours post application . If there is no reaction ,the test is repeated once more on same site. The test is repeated in case there are no reactions if no reaction is observed on third application, the person may be taken as not hypersensitive. if reaction occurs on these application, the subject is hypersensitive
14
Patch Test- Prophetic The purpose of this application is inducing or establishing sensitivity & also detecting the presence of any primary irritant. Test is performed on 10 selected subjects. If results of test are favourable, more subjects may be used The cosmetic to be used is placed on the skin of the subjects for 1 to 5 days. The patch sites are examined & observation are made.
15
Irritant dermatitis No Reaction
Subjects are observed for 3 more days for development of any late reactions. When ingredients are being tested, it is imp to use each ingredient in a specified concentration . Irritant dermatitis No Reaction vehicle
16
Cup Technique Devised for volatile substances that act as primary irritants. Procedure: Volatile substances are soaked into a small piece of absorbed cotton filter paper. This filter paper is placed in the bottom of specially designed cup which is inverted on the skin of forearm of the subject & bandaged.
17
For finished product: skin exposed for thirty minutes
For finished product: skin exposed for thirty minutes. Allows the substance to evaporate. This is followed by routine patch test. The report on patch test must consist of: -concentration of chemical/ agent -amount used -site of application -number of days the patch was left on the skin -period after the removal of patch when observations were made.
18
Disadvantages Quick absorption of potential skin irritant through skin
Rapid evaporation of volatile skin irritant from the patch Small amount and area of skin - as compared to the amount in actual use Short exposure time of skin to cosmetic than in actual use.
19
Repeated Insult Test -Shelanski Test
Apply 0.5 gm or 0.5 ml of test sample to back or upper arms Maintenance at site for 24 hours Record the reactions (if any). Apply second test patch to a different test site Each individual is thus subjected to a series of 10 such consecutive exposures After 24 hours
20
Photopatch Test Performed to test phototoxic substances.
Certain substances are not harmful by themselves but become so when exposed to sunlight. Substances that absorb wavelength between nm have potential to induce phototoxicity. The substances to be tested is applied in duplicate patches in the same manner as for standard patch test.
21
After 24 hours, one of the patches in the pair is exposed to sunlight or UV for 30 minutes and re-covered. One additional site in the adjoining area of skin is exposed to sunlight or UV light as has been done in case of one patch of the pair. Time of exposure is also same as for the exposed patch. After 24 hours the patches are opened & examined. If the test patch shows a reaction and the control site does not, then the formulation is phototoxic.
22
Test for Sensitizing Potential
An individual is not likely to be allergic to a substance on first exposure i.e. the lymphocytes of that individual acquire ability to recognize & elicit immunological response. Thus next exposure of that individual to the substance has chances of sensitizing him. With each exposure his chances of developing hypersensitivity increases.
23
Test for sensitizing potential has been recommended that standard patch tests with same chemical or cosmetic are repeated in the same 200 volunteers after an interval of days. The number of persons who will show positive reaction will represent the sensitizing potential of the substances or cosmetic which has been tested.
24
PROVOCATIVE PATCH TEST
Weak sensitizing agents, do not sensitize a person with first exposure. Repeated exposure to even weak sensitizing agents may make a person hypersensitive. In this test, application of a substance or cosmetic are made on alternate day on same spot of skin on 10 volunteers. Standard patch test is performed after 10 days of last application. The test will show , how many persons have been sensitized.
25
Use Test In use test ,the cosmetic to be tested is actually used & its adverse effect, if any , are observed. 15 volunteers are asked to use the cosmetics. If there is no reaction, cosmetic can be released for trial.
26
Restricted Consumer Test
After the cosmetic has passed test for irritant potential & sensitivity potential , it may be released in market in limited scale. In case, if any adverse reactions are reported during their period of use, the cosmetic should be immediately withdrawn and further, more tests are conducted to make it fit for use.
27
Testing on specific cosmetics
28
Creams Dermatitis may occur with creams containing substances like:
Mercury Salts Salicylic acid Deodorant creams containing salts of Al. bleaching creams containing oxidizing agents & vanishing creams (because of alkalinity) . Perfume Lanoline. (Hydroxy fatty acids)
29
To carry out diagnostic test, rub cream into an unaffected suitable part of body (forearm) for 5 days. If positive reaction occurs before 5 days, rubbing of cream may not be continued. A similar cream available in market for long time without any adverse effect may be chosen as control.
30
Deodorants & Antiperspirants
However phenolic antimicrobials, sulphates and chlorides of aluminium may cause dermatitis or hypersensitivity reactions. Deodorants in powder & cream form can be tested using diagnostic patch test. But perfumes in solution should not be sealed in patch test. Perfumes should be sprayed on the skin & the skin should be kept open. Follow up with Use Test.
31
Depilatories Reducing agents- act as primary irritants, may cause erythema. Sulphides of alkali, alkaline earth and thio-glycolic acid. Intensity depend on conc. , pH & time of exposure. Prophetic test on 10 subjects with well established depilatory as control followed by user test.
32
Procedure Prepare inactive base of depilatory. Prepare dilutions given below one part depilatory + one part base one part depilatory + two parts base one part depilatory + three parts base one part depilatory + four parts base one part depilatory + n parts base
33
Place patches of well established depilatory dilution on one thigh & patches of depilatory dilution to be tested on other thigh of the subject. Examine the patches on 2 thighs after appropriate time. This time could be hours. This test will give an idea about irritant potential of new depilatory.
34
Hair Dyes Hair dyes contain ammonia . More than 1% ammonia is primary irritant. Open prophetic test is carried out on hair dyes . If the hair dye passes this test, it should be tried on 1000 subjects twice.
35
Procedure Hair dye is applied on one square inch skin on the forearm or behind the ear. Repeat it every day for three days (application should not washed during this period). On the other forearm run a control with well established hair dye in market. Repeat the procedure after seven to fourteen days
36
Lipstick Bromofluorescein type of dyes In lipsticks are photosensitive in nature & causes adverse effects. Addition of pigment lakes which act as opacifiers reduce photo-sensitization. Closed prophetic test is carried out on lipstick . After removing the patch , the patch site should be exposed to bright sunlight for several hours to observe the tendency of the lipstick to photosensitization.
37
At least 200 subjects should be taken for this test
At least 200 subjects should be taken for this test. Along with patch test, they should use the lipstick for at least one month. If results of patch test & actual user test are favourable, an extensive user test on additional 800 subjects should be carried out before the lipstick is put on the market
38
Nail polish Resin colour Pigments
In case of nail polish , open prophetic patch test is carried out.
39
Procedure Apply nail polish about 1 sq. inch in area on forearm. An established nail polish should be applied to the other forearm. Do not cover the patch. Apply test nail polish on nails of hand which has patch of test nail polish and control nail polish on the nails of forearm which has patch of control nail polish. Remove patches after 48 hours & after 7-10 days repeat the test on same subjects.
40
Continue the use of nail polish for 2 months
Perform test on 200 subjects. Compare the results of test nail polish & control nail polish. Reactions with test nail polish should not be greater than the control nail polish. If new nail polish passes this test, user test on additional 800 subjects should be carried out before nail polish is put on the market.
41
Hair and Bath Preparations
For eye irritation. Draize and Kelly designed test on eye mucosa of albino rabbit.
42
Leave the eyes of this group unwashed.
Wash the treated eyes with 20 ml warm water after 2 seconds of instillation of test substance. 0.1ml of test substance in conjunctival sac of one eye of nine albino rabbit Wash the treated eyes after 4 seconds of instillation of test substance with 20 ml of warm water.
45
Read the occular reactions with hand slit lamp for 7 days or till any residual injury persists.
Any preparation , which leaves corneal or iris lesions for more than 7 days, is considered severe eye irritant.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.