Keratitis solaris and sunbeds

Area of Science:

• Ophthalmology
• Photobiology
• Dermatology

Background:

• Keratitis solaris is an eye condition caused by ultraviolet (UV) radiation exposure.
• The threshold dose for UV-induced keratitis solaris is established at 40 J/m² for short-term exposure.
• Understanding UV emission spectra from artificial sources is crucial for eye safety.

Purpose of the Study:

• To measure the UV emission spectra of commercial sunbeds.
• To calculate the exposure times required to reach the threshold dose for keratitis solaris.
• To assess the risk of developing keratitis solaris from sunbed use.

Main Methods:

• Emission spectra of 22 sunbeds were measured using a high-resolution double monochromator.
• Measurements covered the UV and visible light range from 250 nm to 500 nm.
• Calculations determined exposure durations corresponding to the keratitis solaris threshold dose.

Main Results:

• Calculated sunbed exposure times for keratitis solaris ranged from 90 seconds to 3.5 hours.
• Shorter exposure times were associated with specific lamp types.
• Risk of keratitis solaris increases without protective eyewear, especially with brief eye openings.

Conclusions:

• Sunbed users lack information on lamp types and emission spectra to determine safe exposure times.
• Inadequate protective measures (e.g., goggles) during sunbed use can lead to keratitis solaris.
• Variable sunbed UV output necessitates user awareness and potentially regulatory oversight for eye protection.