The Top 3 Types of Allergens in Traditional Beauty Products

Ever noticed a patch of dry, red, or unhappy skin and weren’t sure of the cause? Turns out, the ingredients in our makeup can cause irritation and allergic reactions, and some in conventional makeup (read: not clean) are especially common culprits.

Before we discuss the three most common types of allergens, here’s some background info to help you get to the bottom of any skin issues more quickly.

Irritation vs. allergy

While the term “allergic reaction” gets used frequently, there are actually two different types of skin issues that can surface from exposure to cosmetics ingredients: irritation and allergies.

Skin irritation means that the skin has been injured, in this case by coming into contact with certain chemicals. Irritation typically shows up only in the area the product was applied. On the other hand, an allergy triggers an immune system response and can result in symptoms occurring where the product wasn’t directly applied [1]. (Getting even more specific here for any inquiring minds: there are actually two types of allergic reactions. Type I has immediate onset, and Type II delayed onset).

In other words, irritation is your skin reacting and an allergy is your immune system reacting.

Irritations are more common. But since allergy symptoms can also pop up in the area a product was applied, the two can be hard to distinguish from one another based on appearance alone.

Interestingly, irritation often happens the first time a product is applied while an allergy usually (but not always) takes multiple exposures to present itself.

Either way, if a product or ingredient irritates your skin or causes an allergic response, it’s best to avoid that item.

What do irritation and cosmetics allergies look like?

Symptoms vary, but usually a localized patch of skin (where the product was applied) will be red, flaky, or dry. In more extreme situations, you might have hives, swelling, or blistering. Scarring might even occur!

The three most common culprits

While it’s possible for anyone to have a negative reaction to any substance, there are 65 different individual chemicals that are recognized as common allergens (and most but not all are used in personal care products like makeup) [2].

Here are the three most common types [3]:

• Synthetic fragrance ingredients – “Fragrance,” which includes both perfume and scents used in products like lotion or shampoo, is made up of different combinations of chemicals, many of which are implicated in causing negative skin reactions. Clean makeup is formulated without synthetic fragrance.
• Preservatives – Methylisothiazolinone (MIT, or MI) and methylchloroisothiazolinone (MCI), or the combination of MCI/MI, (marketed as Kathon CG or Kathon WT), are three preservatives that commonly trigger an allergic response. Other preservatives commonly used in traditional cosmetics that can create a negative response are quaternium-15, parabens, and thimerosal. Clean makeup is formulated without any of these, but of course should be preserved effectively.
• Hair dyes – Dyes, especially those containing paraphenylenediamine (PPD) and para-toluenediamine (PTD), also used in tattoos, cause irritation.

If you’re trying to figure out where a skin reaction, such as redness, itchiness, rash, lesions, or bumps, might have come from, start by taking a look at your product ingredient lists and compare them to these three categories.

To avoid the allergens in synthetic fragrance, either select clean beauty products or look for the labels “allergen-free fragrance” or “synthetic fragrance free” while shopping. Even the terms “unscented” or “fragrance-free” can mean a product includes fragrance chemicals to mask the smell of other ingredients in your cosmetics. Many products that are apparently unscented may contain a masking fragrance. Labels indicating “fragrance free” or “unscented” are not always safe to use if you’re allergic to the ingredients in fragrance.

To determine which preservatives in your products might be causing problems, you can use the Environmental Working Group’s Skin Deep Cosmetics database to search chemicals and determine which ones are preservatives with high allergenic risk. Keep in mind that an allergy can even form after years of using the same product.

If you’re worried your hair dye might be causing the issue, notice how your scalp responds next time it’s applied. If you notice itching, swelling, or other signs of irritation, that could indicate a problem. You could find a hair dye brand that is known for excluding common allergens.

What should I do if I think I’m sensitive or allergic to a product?

If the reaction you’re having is not severe, you could start with performing a patch test at home. Apply the product to a small patch of forearm skin and notice whether any symptoms occur. Repeat for several days in a row.

If your reaction is more severe or you’d like to quickly isolate what exact chemical is causing irritation or allergy, consider visiting a dermatologist. A dermatologist can do medical patch testing – in which allergens are applied to your skin – which is a reliable method for determining what ingredients(s) you’re allergic to.

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This article was written in collaboration with two scientists: Dr. Laurence Dryer, a beauty scientist, and Dr. Ilene Ruhoy, M.D., neurologist and PhD in Environmental Toxicology.

Do you have any questions or comments about allergens in cosmetics? Leave them in the comments.

For further reading:

• “Diagnostic Approach in Allergic and Irritant Contact Dermatitis,” Medscape
• “The Validated Hypoallergenic Cosmetics Rating System: Its 30-year Evolution and Effect on the Prevalence of Cosmetic Reactions,” Medscape
• “Cosmetic Contact Allergens,” MDPI