Dr. Robert Josephburg, an ophthalmologist and retina specialist at the Westchester Medical Center in Valhalla, N.Y., has warned Congress that swift action is needed to crack down on the use of the laser pens – a more advanced version of the laser pointers regularly used by teachers and professors – before serious injury occurs.
Last week, the world's two most famous soccer players, Cristiano Ronaldo and Lionel Messi, were both targeted by opposition fans during a pair of matches between Real Madrid and Barcelona. Spectators shined the light beams into the eyes of the players, presumably in the hope of distracting them from their performances on the field.
There have been sporadic instances of laser pens being used at American sporting events – most notably last year during a St. Louis Cardinals' game at Busch Stadium – but Josephburg fears that athletics could be particularly susceptible, especially as both the availability of the devices and injuries associated with them appear to be on the rise.
"I have been stunned at the power of these things," Josephburg said in a telephone interview with Yahoo! Sports on Monday. "We are talking about serious damage even if someone is only exposed to it for a few seconds.
"We are seeing young kids getting access to these pointers, and sports is an area to worry about, especially if fans are trying to get an advantage for their team. People have to realize this is not fun and games; it is serious stuff. You are endangering someone's vision. There can be huge repercussions and a real risk of causing at least temporary, and possibly permanent damage to a person's vision.
[Visit World Soccer on Yahoo! Sports]
"If I was a ball player I would be terrified. I only hope Congress acts on this before some real harm is done. The retina is very sensitive and is not made to cope with light of that intensity. If shined for even a few seconds into someone's eyes different symptoms can occur, temporary blindness, blurry vision, spotty vision, the sight may not even fully return."
Laser pointers are not a new phenomenon in international soccer but their use seems to be becoming more widespread. Ronaldo was targeted early last week, during Madrid's 3-1 victory in a Spanish Cup clash in Barcelona.
Fans of Madrid then appeared to retaliate when the teams met again – this time at Madrid's Santiago Bernabeu stadium, over the weekend – with Messi on the receiving end.
Many stadiums specifically prohibit laser pens from being brought inside the grounds, yet identifying the precise location of the culprit is problematic for security staff, especially as a new range of green beams can project intense light from half a mile away.
"If you were in the last row at a football stadium you could aim at someone on the field, easily," added Josephburg.
Most standard laser pens give out a beam of between 3 to 5 milliwatts and are allowed for public sale. The lasers become dangerous when they project a beam of 50 milliwatts or more, Josephburg said. These sort of high-powered lasers, designed for use in the construction industry and medical profession, have sale restrictions imposed. However, a quick internet search provided the option of purchasing a 1.25 Watt beam – more than 200 times stronger than the typical laser pointer – from a foreign vendor.
The newer pointers usually come with a green light and are far more likely to create retina damage. Whereas the older versions could cause harm if a person was exposed to it for a long period of time, the stronger model can have serious effects almost immediately.
Incidents involving laser pointers at U.S. sporting events have been relatively scarce, although a 17-year-old boy was arrested for shining one at San Francisco Giants pitcher Shane Loux during a Major League Baseball game at the St Louis Cardinals' Busch Stadium last year. Cardinals manager Mike Matheny personally identified the youth, who was charged with disturbing the peace at an athletic event.
As with any form of crowd activity, the fear of copycat occurrences must be considered, especially after the high-profile incidents in Spain were noticed by broadcasters and fans alike.
"You can clearly notice it on telecasts, especially games coming from Spain," said Aidan Magee, a journalist and broadcaster with Sky Sports in the United Kingdom. "It is obviously not ideal when you have anyone being endangered in this way, especially two of the most valuable and precious commodities in soccer like Messi and Ronaldo.
"The light is powerful to see. I remember back in the 1980s you would occasionally see the old red laser being pointed at players but it was a small dot and a relatively weak light, especially when aimed from distance.
Magee said European authorities are taking laser points incidents seriously for two reasons: they don't want a high-profile match to be altered if a player is distracted, and they don't want a player to suffer any kind of damage – temporary or permanent.
For all the legal measures that can be put in place against potential sellers and importers of the high-powered laser pointers, Josephburg insists the only effective deterrent is to punish anyone found in possession of or using them.
"There is simply no need for a regular person to have one of these," Josephburg said. "It is one thing punishing the vendor, but they will pop up again. I was able to buy one on the internet and I couldn't believe its strength.
"You have to send a message that this is dangerous and to make people understand the seriousness of it."
Martin Rogers is a soccer columnist for Yahoo! Sports