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Ci 77891 is commonly found in sunscreens due to its ability to block UV rays.

In cosmetics, it acts as a skin conditioner, occlusive, and emollient that give products a rich body.

Concentrations are reported from 0.0004% to 60% with leave-on products going as high as 60% and rinse-off products staying at 8% or below.

The Cosmetic Ingredient Review has concluded this ingredient to be safe as used in cosmetics.

This ingredient does have a comedogenic rating of 3, but this doesn't mean a formula with this ingredient will clog pores. Human testing has proved that any finished product with this ingredient won't automatically make you break out; it really comes down to concentration, formula, and your skin.

Since this ingredient is a triglyceride built mostly from C16 and C18 fatty acids, this ingredient may not be fungal acne safe as that falls into the range the Malassezia yeast can metabolize.

Allergy-wise, the proteins responsible for plant food allergies are taken out of the refined oil. This is why reactions to refined oils are rare even from highly allergenic sources like peanut. Well-designed studies have also shown refined peanut oil is safely tolerated by the vast majority of peanut-allergic people.

However, the issue is with unrefined oils; be sure to reach out to the manufacturer if you have a plant food allergy about the type of oil used in their products.

The other catch for this INCI name is that it doesn't tell you which plants are in the blend so you would need to ask the brand.

This ingredient is often coated with metal oxides like titanium dioxide. Trace amounts of heavy metals may be found in mica, but these metals are not harmful in our personal products.

Mica has been used since prehistoric times throughout the world. Ancient Egyptian, Indian, Greek, Roman, Aztec, and Chinese civilizations have used mica.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.