Unpreserved aqueous solution
Hello, I am working with an unpreserved aqueous solution with pH 3.8. The solution contains only water and one other ingredient. I was wondering for how long is such a solution safe to use topically if it is kept in a fridge at 8°C? I am worried about bacterial colonization but ideally I would like to use the solution for 3 days before making another batch.
Thanks for the help.