[OldDeckHand]

"but I have a lot of trouble believing that the quantities and concentrations of hydrogen peroxide that a teenage hairdresser would have any legitimate business carrying around in her car"

You have a point. OTOH, the peroxide concentrations found in professional hair salons, can be VERY explosive. The concentration of peroxide found in these professional supplies is MUCH greater than what is available OTC, here in the states.

In fact, I believe to purchase such supplies here, one needs a cosmetology license, and I also think records of purchases are also kept for the sales of these products. I don't know what the law is in the UK.

[OldDeckHand]

Oops, I meant...

"the peroxide concentrations found in professional hair supplies"