Home Cosmetic Science Talk Formulating Water quality/expiration date

  • Water quality/expiration date

    Posted by Doreen on January 8, 2020 at 4:21 pm

    For my
    homecrafting, creams, toners, etc., I use 5 liter jerrycans water that’s been
    distilled and deionized in accordance with some German quality standards (see picture
    below).


    I also use this water to rinse i.a. measuring cylinders, the probe of the pH
    meter and prepare buffer fluids for the pH meter. Even with all that I could do
    (in theory) for several months with only 1 jerrycan. I throw the rest away
    after 1 or 2 weeks because it doesn’t feel right to use any longer. (At work we
    throw the water we use for non sterile dermatics away after 1 day, so it feels almost
    awkward to use it so much longer in private!).

    I can get 1 liter bottles from DIY stores, but those are in comparison insanely
    expensive (around 5 dollars for 1 liter of distilled water).

    Another option is use 1 liter bottles of water of a lower water quality (‘demineralized’
    water) from the supermarkets/drugstores (you can’t get distilled/deionized
    water in supermarkets/drugstores here).

    • My
      question is: is it, from a microbial point of view, safe to use the lower
      quality ‘demineralized’ water? Depending on the formula, I can’t always use
      sequestering agents.
    • And
      what would be a safe expiration date for these types of water quality?

    (The preservatives I use the most are Phenonip
    P4 (1%), Germall Liquid Plus (0,5%) and Germaben II (1%).  If I use a blend of phenoxyethanol +
    ethylhexylglycerin (90/10), I follow the hurdle approach (usually I combine it with
    0.1-0.2% disodium EDTA, other Aw reducers like caprylyl glycol, glyceryl
    caprylate).

    ngarayeva001 replied 4 years, 10 months ago 2 Members · 3 Replies
  • 3 Replies
  • ngarayeva001

    Member
    January 8, 2020 at 10:36 pm

    I decided that for my own peace of mind I am just going to boil it. It sounds counterintuitive to boil distilled water but better safe than sorry I guess..

  • Doreen

    Member
    January 9, 2020 at 11:32 am

    @ngarayeva001
    What expiration date have you set for your opened bottles of water?
    It just feels like a waste to throw around 4 liters away from every bottle, but just like you, I’m also afraid of contamination. I don’t boil it though.

  • ngarayeva001

    Member
    January 9, 2020 at 12:20 pm

    I usually buy 5lt packs because it’s cheaper. Normally I would go through it in 2 months which I believe is too long to expect it to stay clean. Do you think there is a problem with boiling? 

Log in to reply.

Chemists Corner