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Japan: Teen injured by LED pen "toy" held 40 seconds in his eye

NOTE: The injury described herein was NOT caused by a laser but by a light-emitting diode (LED). We are including it here because the measured power of 5 mW is similar to laser pointers, and because in mid-2013 the FDA proposed to regulate toys containing lasers. This case of an LED-caused injury may stimulate arguments on both sides. Additional discussion is in blue at the end of this story.

A December 2006 incident has come to our attention. A 15-year-old Japanese boy suffered a retinal injury and visual loss after deliberately looking into a 5 mW violet (410 nm) light emitting diode for a total of about 40 seconds. The LED was in a pen was sold as a toy called “Secret Pen”. The toy appears to consist of an LED light which can excite ink that is invisible under ordinary light but which fluoresces under ultraviolet and near-UV light. The 410 nm wavelength caused photochemical damage to the retina.

According to a 2011 paper in Retinal Cases & Brief Reports, the LED was aimed into the teen’s eye from a distance of about 1 cm. It was held there for about 20 seconds as he deliberately stared into the light. This exposure was repeated the next day. About two weeks later, decreased vision (20/50 on the Snellen scale) was noted in the right eye.
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Italy: Pre-school hit twice, parents fearful

A pre-school in Rome was targeted twice by laser beams in a single month, sending students to the hospital for examinations both times. According to an Italian newspaper report, “the laser beam coming from outside the building hit them in the eyes, hurting them”. The exams showed “eyes puffy and watery, fortunately no serious injuries to the cornea.”

The school board president says that the laser could only have come from apartments overlooking the school, but “we do not know if it is the act of a madman or a child struggling with a dangerous toy.” Police are searching for the perpetrator.

After the second incident, teachers lowered the blinds in the classroom. The report also notes other “increasing” incidents where laser pointers are used against pilots and football (soccer) goalies.

From Corriere Della Sera, “Laser negli occhi dei bimbi”. Thanks to Alberto Kellner Ongaro for bringing this to our attention.