<i>The first time a bottle was opened resulted in a discharge approximately 1.5 inches in length from the shampoo to the metallized film cap seal.</i><p>The dielectric strength of air is ~3kV/mm. That corresponds to roughly a 114kV potential. It's a good thing these bottles didn't contain something flammable like hairspray.
Why don't they name the brand of the shampoo, or the manufacturer? The article says this problem was observed by customers, so this ought to be public information... And since this happened 37 years ago, I'm not sure why they would be worried about libel lawsuits or anything....