The ingredients list water, hydrogen peroxide, phosphoric acid and sodium salicylate as the components.
Mecurochrome might just be a brand/company name?
Yeah that's what I was thinking. Didn't see Alcohol or Mercury in the ingredients. Although I am not sure if labeling regulations are the same in other countries.
I don't know if Phosphoric Acid or Sodium Salicylate dye anything (they are in some liquid test kits, so maybe?).
Never heard of the stuff though (brand), must be a really old brand or just available in certain countries.
EDIT: Just google image searched "Mercurochrome ingredients" and typed in mercury and alcohol along with that in some searches.
I didn't look too much into it, but it seems it did contain mercury and alcohol and/or acetone, at least in the past. Upon looking at google images, it seems there are quite a few companies that have used the name "Mercurochrome", and looking at the ingredients list of some of them, they all are not the same product (many not even containing hydrogen peroxide).
So if the ingredient list is trustworthy, I would think it might be safe to use, given the concentrations everything is in. But again, I know practically nothing at all about Phosphoric Acid and Sodium Salicylate and any ill effects they might have.
With as cheap as the known safe H2O2 (3% H2O2, with the rest being only water) is, I'd highly recommend not taking the risk in using the pictured product and just go buy a bottle of the known safe product. Would make things a lot easier and skip out on a potentially huge headache and big issues with your aquaria (possible fish/invert and plant deaths, contaminating and/or staining the whole tank and it's contents).