Peroxide
Peroxide has many uses in the garden, home.
35% food grade peroxide has no toxic added chemicals---all the rest does and not suitable for human use...
35% peroxide degrades quickly and after 2 or so years, it returns to water........35% is difficult to obtain, they can not ship it and only deliverable by truck and normally in barrels for food companies.
The internet / amazon etc. sales 3% food grade peroxide, basically someone mixes 35% with distilled water and then bottles and sales. Stores sale 3% and it is too toxic for human use. Even 30% peroxide by the barrel is made toxic---only 35% food grade is left free of added poisons by design.
Sadly those selling 3% food grade, even calling them selves a chemical company, etc. via amazon, etc. generally are just selling water with a tiny amount of peroxide so weak that it is surely less than 1% OR it has lost the peroxide. Mostly customers have no idea and believe they are buying the real deal and have no idea that it is worthless. Cheap, often like $20 a gallon, but not so cheap when it is just worthless water.
To make REAL 3% food grade, you have to obtain real 35% food grade first and if it is not fresh made---odds are it is much lower than 35% and then that makes it impossible to know if you made 3% and most uses are calculated with a base of 3%.