Here is one specification that I found searching the net:

Maker xxxxxx
Concentration 35%
Stability 0.30 ml/min (max)
Acidity (as H2SO4) 0.015-0.03 g/100ml (max)
Nitrate (as NO3) 125 ppm (max)
Phosphates (as P2O7) 225 ppm (max)
Sulphate (as SO4) 5 ppm (max)
Chloride (as CL) 5 ppm (max)
Arsenic (as AS2O3) 1 ppm (max)
Heavy Metals (as Pb) 2 ppm (max)
Total Carbon 500 ppm (max)
Alkyl Anthoquinone (as ETQ) 10 ppm (max)

Other producers will have different specifications for 'food grade'.

So my question is : What is 'food grade'?
I mean, is there any "common" or "standard" or "generaly accepted" specification to make the product 'food grade'? Or anyone can stick a label with 'food grade' on it that that's okay?

Or the user must study chemistry and medicine before buying 'food grade' H2O2?

Why was this posted in the sleep disorder forum?