Eyeliner has long been used to set off eyes and accentuate lashes, but new research is indicating that eyeliner applied too close to the inside of your lid may not be so kind to your eyes. While cosmetic companies have recommended using waterproof eyeliner when applying near the tear film of the eye, this team of researchers set out to see how much of that eyeliner still ends up on the surface of the eye and whether that might have any impact on the health of the eye.
How does the eye normally protect itself?
Your eye is covered by a thin (but complex) layer that protects your eye from drying out and being damaged by chemicals or dust that circulate through the air. This layer is called the tear film and is made up of a layer of mucus, a layer of water and a layer of oil. In addition to protection, this layer nourishes the tissues on the front of the eye to keep them healthy, lubricates the surface of the eye so the lid can pass easily over it, and keeps the front of the eye clear so that light passing into the eye isn’t blocked by particles that might otherwise get stuck on the surface. When particles do enter the eye, the tear film helps to keep that particle from sticking and allows it to be washed away by the natural movement of the eye and lid.
How does eyeliner factor in?
Some women apply eyeliner behind the line of the lashes, close to the waterline. While cosmetic companies have advocated using waterproof eyeliner in these circumstances, this recommendation fails to take into account the complexity of the tear film. While there’s water on the surface of the eye, there’s also oil and mucus, which is made from proteins. While the waxes and oils in waterproof eyeliner repel water, the oils would be attracted to those waterproof compounds and proteins may interact to some degree.
On top of that, the eyes and eyelids are full of muscles. There is a tiny group of muscles that line the edge of the eyelid and help to keep the eyelashes properly oriented. As these move throughout the day, they could also potentially push eyeliner against the eye. The researchers who performed this study made that observation and wondered how much eyeliner applied in this area might be drawn up into the eye.
What did the researchers do?
The researchers recruited three women for the study and first looked at their eyes without makeup or contacts. Eyeliner was then applied outside of the lashline with an eyeliner pencil. The team then made films of the subjects’ eyes at periodic time intervals over the next four hours using a device called a slit lamp that allows you to see the surface of the eye. After 24 hours, the subjects came back and had eyeliner applied inside of the lashline on the inner edge of the lid with a new pencil. Their eyes were filmed for another four hours.
What did the researchers find?
The team saw particles of the eyeliner start moving into the eye almost immediately after applying it inside the lid. That amount continued to grow for between five and 30 minutes after applying, after which the number of particles declined and was back to normal by about two hours after applications. When applied outside the lashline, some eyeliner still entered the eye, but more slowly and at lower levels than those seen when the eyeliner was put inside the lid line.
How does this affect me?
The researchers point out that this is the first study to look at the movement of eyeliner into the eye. While they didn’t see any direct irritation or damage to the eye during their study, they note that the study was brief and doesn’t consider the effect of having eyeliner enter the eye day after day for years. They point out that the oils in the eyeliner could break up the tear film, decreasing the protection of the eye and possibly leading to more irritation, especially in those who already have dry eyes and use eye drops. In addition, they note that the particles of the eyeliner could collect on contact lenses present in the eye. This can cause clouding of the lens and make vision difficult unless the lenses are cleaned on a regular basis. If you’ve been experiencing eye irritation or cloudiness when wearing your contacts, you might think about taking a few days off from eye makeup to see whether it affects these problems.