Sold by the gram, $0.035/g. Please buy or bring a bottle.

Water-soluble, made in Canada.
Sodium Lactate is a combination of 60% Sodium Lactate and 40% Water.

Sodium Lactate is naturally derived from the fermentation of Lactic Acid. It is a clear colourless viscous liquid with a mild odour. Sodium Lactate is considered to have antioxidant properties and can improve bacterial stability when used in combination with a full spectrum preservative. Please note that Sodium Lactate is not an effective preservative in itself but used in addition to a full spectrum preservative to improve bacterial stability (Bacteriostatic agent).

Sodium Lactate is also considered to be a natural humectant (draws moisture to itself) and is frequently used as a substitute for glycerin in lotions, creams, hair care products, and cosmetics. When added to cold process soaps, it is said to harden the soap faster, add creaminess and extend its shelf life in the shower (does not melt easily). It is said to improve the appearance of the finished soap and ease with un-molding a batch of soap.

Usage:
• It can be used in a wide variety of personal care formulations to improve skin and scalp moisturization, and lighten complexion.
• Soluble in water and alcohol.
• Acts as a Bacteriostatic agent when combined with a full spectrum preservative.
• Recommended use levels in a finished formulation are 1 - 3%.
• It is a pH control agent.
• Compounding procedures: May be added to the water phase with heat to ensure proper incorporation.

I use sodium lactate in Natural Genital Lubricant and Moisturizer http://www.anarreshealth.ca/node/688
and
it's the active ingredient in natural spermicide Contragel http://www.anarreshealth.ca/node/519