| NEW YORK, July 3
NEW YORK, July 3 (Reuters Health) - Just in time for July
4th, a U.S. study shows for the first time how fireworks can
There are more than 2,000 eye injuries from fireworks every
year in the United States, most occurring during Independence
Day celebrations, but the exact mechanism behind the injuries
had escaped researchers until now.
Some had argued it takes flying shrapnel to make eyes bleed
or rupture, while others thought pressure waves from the
explosion itself are enough - in which case safety goggles might
not offer adequate protection.
Scientists found that blast waves from explosions mimicking
commercial firecrackers, even at short distances, were too
feeble to make an eyeball burst. They conducted the tests on
eyes taken from human cadavers and published the results on
Tuesday in the Journal of the American Medical Association bit.ly/MvXYT6.
"This for the first time scientifically proves you have to
have the impact from an object such as a bottle rocket to cause
serious eye injuries," said Stefan Duma, who heads the Virginia
Tech-Wake Forest University School of Biomedical Engineering and
Sciences. Duma, who led the new research, said he is a big fan
"If you remove the projectile, you dramatically reduce the
risk," he told Reuters Health.
For the study, his team used human eyes from an eye bank in
"We put instrumentation into the eye," said Duma, who has
spent two decades developing techniques to measure eye injuries.
"Then we detonate charges at various distances from the eye."
Even at less than three inches, the researchers found, the
blast damage to the eye was limited to surface scratches -
called corneal abrasions - which usually heal on their own.
The scratches got bigger the closer to the eye the explosion
took place, and high-speed videos showed they were caused by
unspent gunpowder flung onto the eyeball by the blast.
Dr. Terrence O'Brien from the Bascom Palmer Eye Institute at
the University of Miami said he has seen eye injuries from
fireworks ranging from minor abrasions to complete loss of an
"Of the 2,000 injuries every Fourth of July, the vast
majority are in young adults and children," O'Brien told Reuters
Health. "It's ironic that while celebrating our independence
they lose their visual independence due to sight-threatening
He welcomes the new results, adding that they should help
guide policy decisions on fireworks safety. Still, he pointed
out that the study has some significant limitations, including
that it was done in dead tissue.
"We have to understand, this is a somewhat contrived
experiment," he cautioned. "In the real world, it's not as
controlled as this."
For instance, although Duma and his colleagues used charges
similar to what are found in commercial firecrackers, a lot of
real-life injuries are from homemade fireworks, which may be
more powerful, O'Brien said.
"Certainly we don't want to ground fireworks, but they
should be carried out by professionals," O'Brien said.
For those who prefer the hands-on approach, added Duma, who
has his own remote-controlled launchers ready, "first and
foremost you have to have parental supervision. If possible,
having safety glasses would be the best thing. It's important to
have kids wearing these from a very young age."
(Editing by Genevra Pittman, Michele Gershberg and Kenneth