Unfortunately as this urban myth seems to stretch back to at least 1967 I am not sure you will ever find where that individual heard the story first.
Just to add to the myth busters who have already posted this comes from the "Snopes-rumor has it" site (American of course which is where it seems the myth first saw the light of day). It gives some possible indication of where the story first cropped up.
"For many, their first contact with the 'hapless welder' version of the scare came from a badly blurred photocopied memo warning against the dangers of engaging in welding while wearing contact lenses. Often this memo began with the headline "TWO RECENT INCIDENTS HAVE UNCOVERED A PREVIOUSLY UNKNOWN PHENOMENON OF SERIOUS GRAVITY." (Modern versions have replaced welding with barbecuing as the activity fraught with danger for contact wearers.)
There were no such incidents demonstrating a "previously unknown phenomenon of serious gravity" affecting those who welded or barbecued while wearing contact lenses, but the memo was often taken at face value, even by respected news outlets. The American Academy of Ophthalmology has traced those rumors back as far as 1967, when a worker for Bethlehem Steel and a welder for United Parcel Service were said to be the victims. Not only haven't such accidents happened, nearly every reputable medical and industrial source in the field says they couldn't happen.
Dr. Barry M. Weiner, a physician at the University of Maryland Hospital, responded to a local variant of the rumor: "It is a physical impossibility to dry up the fluid in your eyes. You'd have to stick your head in a blast furnace to do that. And removing your cornea would be like pulling off your ear."
Yet there may be a grain of truth in the welder story anyway, even if it has been distorted almost beyond recognition. According to the sci.chem FAQ:
[A] Bethlehem Steel welder in Baltimore who, on the 26 July 1967, accidentally caused an arc flash that hit his hard contact lens. He waited until the next day to report eyesight problems, and an ophthalmologist found severe ulcerations on his cornea, but attributed the damage to the wearing of the hard lenses for 17-18 hours after the incident. The cornea healed completely in a few days, with no permanent vision loss, and investigators found no link between the damage and the arc flash, but the myth of the welder removing parts of the cornea with the lens, and consequently being permanently blinded, continues.
Unlike the legend, the worst of the man's injury came from his not seeking treatment in a timely manner, not the horrific run-in with the arc. The fellow also made a complete recovery — a far cry from the "blinded for life!" element of the legend".
Read more at
http://www.snopes.com/ho....asp#VEPscM0cKCuH4RHH.99