Why Distilled Water for Lotion?

[Misschief]

Not Carolyn, but I want to contribute anyway. My notes suggest about 0.02% by weight EDTA powder based on the total batch weight of lotion. Yes, that's a teeny tiny amount.

Disclaimer: I have just recently started to include a chelator in my lotions, so my real-world experience is limited. Hopefully Carolyn will share what she recommends -- she has a lot more experience to back up her recommendations. @IrishLass is another person who uses a chelator in lotion -- perhaps IL will also share what works for her.

You will want to use DIsodium EDTA for products like lotions that have a neutral to acidic pH (pH at or below 7). TETRAsodium EDTA should be used in soap, because soap is alkaline (pH above 7).

In addition to extending the shelf life of fats in a lotion, the use of a chelator also boots the effectiveness of the preservatives added to lotion to inhibit microbial growth. Certain trace metals are required to support living organisms. If the chelator immobilizes those metals, then microorganisms in the lotion will find it harder to reproduce and thrive.

Just to be clear -- A chelator is NOT a preservative. Use it IN ADDITION TO a broad spectrum preservative, not in place of a preservative.

Thank you, @DeeAnna!

 

[johnnyusa]

also bc it's easier for soft rather than hard water to accept whatever it is that we are trying to impart into it, like some scent, lye, clay, or whatever. We want to basically dissolve stuff in the water or use the water as a medium for another substance, but that's more difficult w/ hard water that already has a high level of total dissolved solids (TDS).
Soft water is empty and impressionable, whereas hard water is crotchety old man fixed in his ways.

Distilled water has 0.5 ppm TDS, rain water is 20ppm TDS, spring water is 50ppm TDS, & the tap water i won't even feed to my dog has about 350ppm TDS

Dissolved solids" refer to any minerals, salts, metals, cations or anions dissolved in water. Total dissolved solids (TDS) comprise inorganic salts, principally calcium, magnesium, potassium, sodium, bicarbonates, chlorides, and sulfates and some small amounts of organic matter that are dissolved in water.

 

[MellonFriend]

also bc it's easier for soft rather than hard water to accept whatever it is that we are trying to impart into it, like some scent, lye, clay, or whatever. We want to basically dissolve stuff in the water or use the water as a medium for another substance, but that's more difficult w/ hard water that already has a high level of total dissolved solids (TDS).
Soft water is empty and impressionable, whereas hard water is crotchety old man fixed in his ways.

Distilled water has 0.5 ppm TDS, rain water is 20ppm TDS, spring water is 50ppm TDS, & the tap water i won't even feed to my dog has about 350ppm TDS

Dissolved solids" refer to any minerals, salts, metals, cations or anions dissolved in water. Total dissolved solids (TDS) comprise inorganic salts, principally calcium, magnesium, potassium, sodium, bicarbonates, chlorides, and sulfates and some small amounts of organic matter that are dissolved in water.

Great information!

 

[user 29214]

@Misschief
I use disodium EDTA at 0.20%, following recommendations from Makingskincare (Jane Barber). I also see that is the common usage rate mentioned in the Lotion Crafter’s product page.