Peptide Crafters ran a study and checked the quality of BAC water from Amazon. Most look like pure garbage. No benzyl alcohol whatsoever or inadequate levels make your reconstitutions unsafe in the fridge. Then many overshot pH - and most peptides are unstable in overly alkaline pH water. Shocking.
https://peptidecrafters.com/the-crucial-role-of-solvent-quality-in-in-vitro-laboratory-research/