Labels emblazoned with claims like dermatologically tested or hypoallergenic instil a certain level of confidence that a product won’t harm or irritate our skin. If you have sensitive skin, or have had a skin reaction to cosmetics in the past, you might be particularly attuned to these sorts of terms, but what do they mean and how do you know you can trust them?
In Australia, cosmetic ingredients are regulated by NICNAS, part of the Department of Health, who assess the safety of all new ingredients. However, this shouldn’t be taken to mean that all cosmetic ingredients are completely harmless. There are many ingredients capable of causing skin irritation or allergic reactions. To help ensure a product is suitable for sensitive skin, that product must be tested in its final form.
Dermatological testing assesses a product’s potential to cause irritation and sensitisation (allergic reactions) on the skin. For a product to be dermatologically tested, there is a process involved called repeat-insult patch testing, and it’s conducted on human volunteers. A small sample of the product is applied to a target area of the back, then covered with either a semi-occlusive or occlusive patch (like a surgical dressing). An occlusive patch is sealed on all four sides of the target area, helping to drive more of the product into the skin, and making a reaction more likely. A semi-occlusive patch is similar, except that it’s open on two sides, like a typical Band-Aid, allowing some air to flow around the site. The patches are left on for 24 hours, and after 48 hours the skin is ‘read’ by a qualified expert who looks for any signs of redness or swelling. This process is repeated 9 more times on each of 50 test subjects, giving a total of 500 patches, all of which must remain clear for the sample to pass. The product must also pass a challenge test, where the sample is applied to each volunteer again after a few weeks, this time on a different location, to ensure they haven’t been sensitised to any of the ingredients. Often, to really put a product through the wringer, the panel of testing volunteers will include at least 25 people with sensitive skin.
The term ‘hypoallergenic’ is not regulated, so there’s no standard testing a product needs to pass to qualify. Essentially, it’s self-governed by the company making the claim. At the very least, a product should be free from common allergens, such as fragrance and certain preservatives. It should also have passed repeat-insult patch testing using a sensitive skin panel and occlusive patches, the most challenging conditions. If you’re curious or concerned about the testing behind a particular product, try getting in contact with the manufacturer. Most companies will be more than happy to share with you how a product has been tested.
There are no guarantees
Even if a product is dermatologically tested and free from all common irritants and allergens, and it’s run the gamut of available testing, there are still no guarantees that it won’t cause a reaction on your skin. If you have sensitive skin, it’s a very good idea to patch test any new skincare products on a small area of skin before incorporating them into your routine.
How to patch test skincare products:
1. Choose a test area – This should be near the area you intend to use the product. E.g. for face products, try the side of the neck or behind the ear.
2. Stop using other products on that area – and only test one new product on that area at a time. It’s important to control this experiment as much as possible, so that if a reaction occurs, you can be sure which product is causing it.
3. Apply the product – You only need to use a tiny amount. If it’s a rinse off product like a cleanser, make sure you follow the directions. Even on normal skin, cleansers can often cause redness/itchiness if not rinsed off properly.
4. Monitor the outcome – A reaction will usually be noticeable within 24 hours, so if you develop a severe rash obviously discontinue use of the product. Some reactions could take up to 96 hours, and repeated exposures, to develop, so it’s important to repeat the process for a few days before diving in2. Also be aware that some products, such as those containing AHAs or other acids, may cause slight tingling or itching with the first few uses. This is normal and should subside within 15-20 minutes or so.
If you experience a severe skin reaction, see your healthcare professional. Anaphylactic shock due to cosmetics is possible, so if you experience severe swelling or have difficulty breathing, seek immediate medical attention.