Ophthalmology Times: The Harm of Vape Aerosol to the Eyes

On February 15, the overseas ophthalmology news magazine Ophthalmology Times, citing research by ocular surface disease expert Dr. Periman, reported that because e-liquid contains many chemicals and its ingredients may also be unregulated, the aerosol produced by vaping devices may affect the eyes in different ways.

The full text is as follows:

High nicotine levels are common

Unlike the nicotine content naturally present in cigarette tobacco, the amount of nicotine extracted into e-liquid is not controlled and is often unknown.

Doctors are seeing illnesses caused by nicotine (“nic sick”), especially among adolescents. These include seizures, anxiety, depression, cognitive impairment, and difficulty concentrating.

Nicotine’s effects on the eyes include constriction of the pupils and reduced retinal activity visible on electroretinography (ERG).

E-liquid is full of other chemicals

In addition to nicotine, e-liquid ingredients include acrolein (2-propenal), an aldehyde that can severely limit regulatory T cells, a mechanism that may activate and lead to chronic dry eye disease (DED).

Carriers and flavoring additives can also cause lung toxicity and directly activate transient receptor potential (TRP) channels in the ocular surface immune system and corneal nerves.

Some chemicals in aerosol may also activate the immune mechanisms involved in chronic DED. Other potential ingredients also have additional health effects, including nitrosamines, benzaldehyde, benzyl alcohol, propylene glycol, and ethylene glycol.

Ingredients are basically unregulated

After manufacturing changes, vitamin E was added to certain vape cartridges, and some users developed severe lung toxicity and even required lung transplants.

A retrospective analysis of e-liquid ingredients showed that 100% of the cartridges used by affected patients contained vitamin E, whereas vitamin E had never previously appeared in the same cartridge brands. The viscous ester was used as a filler, but it is not safe to inhale.

Without regulation, there is no way to know whether or when other potentially hazardous substances may be added to e-liquid in the future. A brand’s reputation does not guarantee safety for our patients’ lungs or other organ systems.

Researchers are now studying OSD and vaping

A recent paper compared ocular surface findings in vape users and non-users, and found that vape users showed staining and reduced tear breakup time.

Schirmer test results in the vape user group were inconsistent, which may be attributable to the compensatory phase of the lacrimal glands in dry eye disease; this compensation may gradually disappear over time. 

What should we do?

After reading more about the chemicals involved in aerosolization and their effects, I am more convinced than ever that treatment for ocular surface disease (OSD) should include educating patients about natural and self-induced environmental challenges.

In particular, if they are exposed to chemicals that may affect the inflammatory cycle, treatments that help reduce inflammation should be used, such as omega-3 fatty acids (HydroEye, ScienceBased Health), cyclosporine (Restasis, Allergan; Cequa, Sun), lifitegrast (Xiidra, Novartis), intense pulsed light therapy (Optima IPL, Lumenis), and thermal office-based treatments (TearCare, Sight Sciences; iLux, Alcon; and LipiFlow, Johnson & Johnson Vision)—all of which may help shift things in a positive direction.

Most importantly, I have added vaping to the intake form for my practice’s “dry eye service.” I want to know whether patients use vaping devices and whether they are frequently exposed to secondhand aerosol.

My patients need to understand the risks they are taking with their eyes and their overall health. Efforts by physicians to educate patients often improve patient health outcomes.