Students who were exposed to ultraviolet radiation in a lab for Life and Physical Sciences A: “Foundational Chemistry and Biology” last week can expect temporary burning, irritation, and minor vision loss, but no lasting harmful effects, according to a Harvard Medical School ophthalmologist.

Justin M. Kanoff, director of the Eye Trauma Service for the Harvard-affiliated Massachusetts Eye and Ear Infirmary, said that most students who were injured in the accident suffered only from a “corneal burn,” an acute injury to the front-most part of the eye.

At least five LPSA students were sent to Massachusetts Eye and Ear later that day due to eye injuries.

According to Kanoff, when the cornea is exposed to UV light in high doses, some corneal cells die and are sloughed off, causing the painful irritation reported by some LPSA students.

Normally, corneal burns have no long-term effects on the eye, but rather heal in a matter of days through treatment with topical antibiotics and anti-inflammatory eye drops, he said.

“Most people who have surface damage [to the eye] heal without problems,” said Kanoff, who had access to patient’s records from the incident.

Citing patient privacy concerns, Kanoff could neither confirm nor deny whether some students had experienced burning in deeper structures of the eye, such as the retina, the light-sensitive organ that connects directly to the optic nerve.

“Exposure to UV light can cause injuries throughout the eye,” Kanoff said. “The front of the eye becomes very irritated. Luckily, not a lot of [the radiation] gets to the back of the eye.”

He said that suffering from retinal burns could cause phototoxicity—irritation caused by light exposure—that “may not heal.” He added that injuries to the retina can cause problems with visual acuity, meaning the visual field becomes blurry and straight lines appear wavy, or can cause scotomas—patches of blindness in the visual field. These effects could be permanently debilitating.

Kanoff said that eye injuries from radiation exposure are fairly uncommon because most people exposed to UV light wear protective goggles.

Students in LPSA were completing the course’s final lab, which included viewing DNA strands using a blue light transilluminator, a device that emits UV light.

The student’s lab instructions did not include directions to use goggles for this part of the experiment, and it remains unclear as to whether students were verbally instructed to do so by the teaching fellows present.

Harvard has since launched a formal review of the incident.

—Staff writer Benjamin M. Scuderi can be reached at bscuderi@college.harvard.edu.