Projected Explosive Material, Not Blast Pressure, May Be Primary Cause of Eye Injuries From Fireworks

 

 

“Injuries from fireworks are prevalent among youth. The eye is the most frequently injured body part and accounts for more than 2,000 injuries annually. Although it is suggested that the pressure wave caused by explosions (i.e., blast overpressure) can cause eye injury (scleral bleeding and globe rupture), there is no clear evidence to support this,” writes Vanessa D. Alphonse, B.S., of Virginia Tech-Wake Forest University, Blacksburg, Va., and colleagues, who conducted a study to assess the mechanisms involved in eye injuries caused by fireworks.

As reported in a Research Letter, human cadaver eyes were procured from the North Carolina Eye Bank. Due to the variability of consumer fireworks, 10 gram charges of gunpowder were used to simulate fireworks in a controlled, repeatable manner. Eyes were pressurized to physiological human intraocular pressure before testing. A total of 18 open field blast tests were conducted at varying distances from the cornea. The researchers found that minor grain-sized corneal abrasions were the only injuries observed. The abrasion size and pattern suggested unspent explosive material was projected onto the eye, which was confirmed with high-speed video. The firework blast overpressures did not cause serious eye injuries. “This study provides information about injury mechanisms of fireworks that could aid in public policy decisions regarding firework laws and in the design of protective equipment.”

(JAMA. 2012;308[1]:33-34.