Vaping May Damage the Outer Coating of the Eye, Impair Vision

A close-up of a closed eye. Archive Photos/Getty Images

Vaping is linked to certain health risks to the eye, especially pertaining to the outermost layers of the eye that play an important role in ocular comfort and vision.

According to a recent systematic literature review led by researchers at the University of British Columbia, the effect of vaping on the ocular surface is “not benign.”

“There are significant risks that vaping can pose to the ocular surface,” said the authors of the review, published in the Journal of Clinical Medicine in late April. “Hence, it is necessary to develop appropriate risk communication tools given the increasing popularity of this activity.”

Dr. Tanya Khan, an oculoplastic surgeon who was not involved in the study, told The Epoch Times that she has been increasingly noticing the reporting of dry eyes and redness among younger people who vape.

“I think we are probably still seeing only maybe the short-term effects,” Dr. Khan said, “as vaping has been a fad of maybe less than 10 years’ duration. So I’m sure over the coming years, we'll start to see maybe some more long-term data.”

The authors noted in their literature review both unintended and intended exposures of the eye to e-cigarettes that can cause damage. With regard to unintended exposure, they wrote that some eye damage can occur because of explosions of e-cigarettes or because of the vaping liquid or other vaping products breaking off.

“These explosions are difficult to predict and therefore to avoid,” the authors wrote, noting that corneal trauma was the most common form of ocular surface injury from such explosions.

According to the paper, e-cigarette explosions can also cause trauma to other parts of the eye’s surface, including bleeding underneath the conjunctiva and the accumulation of black particulates in the outer eye surfaces.

Vaping Affects the Tear Film and Cornea

During vaping, the vapors from the e-cigarettes can contact and affect the eye’s surface—mainly the tear film and the cornea, which form the first and second layers of the eye’s surface

Regarding acute exposures, the authors cited a study involving 64 participants who were asked to take a dose equivalent to 10 puffs of an e-cigarette. After vaping, the stability of participants’ outer eye surfaces was affected. However, the findings were insignificant.

Chronic exposures through vaping have been linked to various health risks, including cancers of the eye surface, change in tear film stability and quality, tear production, corneal thickness, average loss of meibomian glands, and dry eye symptoms and or ocular irritation, the authors wrote.

Some components in the vaping liquid can be carcinogenic. If the liquid is not heated correctly, formaldehyde—a carcinogen—can be released. Certain flavorings may also contain diacetyl, which may cause severe lung disease.

Importance of the Tear Film to Vision

Chronic exposure to vaping is linked to a destabilized tear film layer and increased tear production.

The tear film coats the eye’s surface and protects, preserves, and lubricates the eye. Its smooth surface is also important for light refraction and vision.

Dr. Majid Moshirfar, adjunct professor of ophthalmology at John A. Moran Eye Center at the University of Utah, whose own review from April 2021 was cited in the recent review, said the health of the eye film is very important for maintaining vision.

“When the light hits the surface of our cornea, first, they actually hit the tear film layer, and then after that, they penetrate throughout the rest of the cornea, and then the rest of the optical system,” he said.

“The tear film and the integrity of the tear film directly impacts the ocular surface. So if you don’t have a good tear film, or if you don’t have a stable tear film, you can have not only symptoms of dryness but also impact on your vision in terms of visual fluctuation. That can make you feel like you’re not seeing as good as you would like to.”

Meibomian glands are tiny oil glands that line the eyelids.

Dr. Khan and Dr. Moshirfar told The Epoch Times that the most common symptoms that they see being reported in patients are dry eyes, which may lead to eye redness.

Dr. Moshirfar noted that he was prompted to look into the effects of vaping when he started seeing young patients coming to him with severe eye dryness that he could not explain.

Some patients may also have already thinned corneas, which may impede their vision given the important role that the cornea plays in refracting light. If the tear film is then destabilized, the cornea can get exposed and further damaged over time.

Vape Ingredients Oxidize Tear Film, Restrict Blood Vessels

The vape fluids contain aldehydes, glycerol, and other volatile organic compounds that can interact with the lipid layer, or the outermost layer of the tear film.

Dr. Moshirfar, in his review, suggested that different flavoring may give rise to different compositions that can affect the tear film layer in different ways.

“All these volatile organic compounds and these micro particular material that are created as a result of that secondhand aerosol can impact the integrity of your tear film by creating an oxidative insult and damage the integrity and structure of the tear film, which causes you to have these ocular surface symptoms,” he said.

The nicotine in vapes also constricts blood vessels in the eyes, which can affect tissue repair and health of the eyes and the surrounding areas, Dr. Khan said.

She said she would always counsel her patients to stop smoking and vaping—especially when considering surgery—because the vasoconstrictive effects of nicotine can interfere with wound healing.

Dr. Moshirfar’s own paper also mentioned that nicotine may adversely affect the retina of the eyes. The retina’s role is crucial in visual acuity, detecting color, and processing the light that enters the eye into a coherent, perceivable image within the brain.

Nicotine has been shown to interact with receptors in the retina, and experiments in animals have shown that it can increase the release of dopamine and glutamate in the cells within the retina.