[Holmes12]

Again thank you, and sorry, that was a lazy question. Having posted it I completed some research and found some very interesting stuff.

Flamesabers:

As far as I know, the product is sold everywhere as PABA.

Yes indeed it appears to be, and it is also in many food sources, in my favourite savoury breakfast spread and multi vitamin tablets, in low levels, so I've been taking PABA without knowing it.