A study published in the U.K.’s Eye journal in January, 2016 titled “Low-energy Light Bulbs, Computers, Tablets and the Blue Light Hazard,” concludes that blue light is not a health concern. The study’s lead author, John O’Hagan, head of the Laser and Optical Radiation Dosimetry Group of Public Health England in Chilton, U.K. asserted, “Even under extreme long-term viewing conditions, none of the low energy light bulbs, computers, tablets and mobile phones we assessed suggested cause for concern for public health.”

Because the Eye study seems to contradict much of the research that informs the marketing of blue light filtering lenses and other related products, VM asked several industry technical experts to assess the findings.

Pete Hanlin, director of technical marketing for Essilor, pointed out that this study may have been at least partially designed “to reassure consumers that CFLs and LEDs are not going to pose an immediate threat to their vision. It is also important to realize that the guidelines on which the paper was based (ICNIRP Guidelines on Limits of Exposure to Incoherent Visible and Infrared Radiation) are related to short-term (not long-term) exposure.”

David Sinnott, vice president, global product management, Carl Zeiss Vision Care business group, concurred. “It is no surprise that they found no risk according to those standards, but those standards only address the risk of acute damage from a relatively short exposure,” he said.

Anne-Marie Lahr, OD and Thomas Gosling, OD of Hoya Vision Care, agreed with the authors’ conclusion that High Energy Visible blue light is not hazardous under these conditions. In acute viewing episodes, however, Dr. Gosling noted that the main concern with HEV blue light exposure that is largely held by researchers and ECPs pertains to its effects over years, not hours or days.

Alan Burt of VSP Optics Group said that although the recent paper published by O’Hagan, et al. is an interesting contribution to the current body of information on blue light, there are important points to consider:

It is a panel-reviewed symposium paper which examines only retinal damage, and does not address other implications from blue light exposure such as visual strain and fatigue.

The materials and methods used in simulating “extreme long-term viewing conditions” from “reasonably foreseeable exposure” to blue light from devices, comparing that level to “natural exposure” from “long-term viewing” resulting from “staring at the sky,” are not validated bases for making predictions about chronic exposure to blue light over a prolonged duration of years or decades.

Its cited references do not necessarily represent the most current information on the subject, and may have been superseded by more recent peer-reviewed studies.

Ophthalmologist and macular researcher Adam Berger, MD, who represents BluTech, concluded, “The article is factual, but it is not relevant to the disease processes we are trying to mitigate by filtering out blue light.” He noted that while the study confirms that “your iPad is not going to cause acute damage to your retina in the short term (like staring at an eclipse of the sun),” [it] “does not address the long-term chronic cumulative insult that leads to Age-Related Macular Degeneration.”

The consensus among these optical experts is that the Eye study’s assertions regarding “long-term viewing conditions” actually references acute periods of blue light exposure as opposed to exposure over months and years. However, because digital devices are relatively new, there aren’t yet any conclusive, multi-year studies that establish a link between long-term exposure to high-energy blue light from digital screens and retinal damage. However, there are many scientific sources which support this correlation, as cited in the accompanying sections and in our Blue Light Research Compendium on VisionMonday.com.

The optical experts also agree that ECPs should educate patients about the potential years-long effects of increasing exposure to HEV blue light and recommend one of the many lenses designed to limit its transmission to the eye.