This month I want to address a topic I see pop up on the message boards pretty frequently: use of homemade or diluted products.
I pretty frequently read of products such as hair conditioners or styling products being diluted with water and used as daily leave-in treatments. Many people also enjoy making some of their own products, using natural ingredients such as honey, aloe vera, water, and various oils often found in the kitchen. The results obtained from these can be wonderful. But it is important to exercise a bit of caution regarding spoilage.
Products purchased off the shelf have been very carefully formulated and pretty exhaustively tested in laboratories by microbiologists in order to ensure that the correct amount of preservative is present in order to prevent growth of fungi, mold, and bacteria (sounds yummy, huh?). These antimicrobial compounds also act as antioxidants, protecting the chemical stability of the product. The optimal level of preservative per unit volume is calculated and used in order to be just sufficient for that particular bottle in ordinary use conditions for a specific period of time. It is important to not use too much preservative because preservatives themselves can be harmful to humans or cause allergic reactions. Therefore, there is not typically an excess of preservative in most products.
For this reason, when a product is diluted with water (especially tap water) and placed into a non-sterile container (which is most typical in any household), the preservative level is reduced by as much as 100 times or more. This diluted product is then often stored in the hot and damp conditions of a bathroom. These conditions are perfect for the breeding of all sorts of living entities that just love to live in water and eat organic molecules (such as those found in your conditioner).
Lacking the inhibition of a safe amount of preservative, microorganisms can grow unchecked and create a genuine health risk for anyone using them. Another potential effect of significantly diminished preservative concentration is degradation of the molecules in the product itself via oxidation from environmental exposure. This can cause development of noxious odors or the formation of potentially dangerous degradation products. At best, it can simply render your product ineffective.
The risk of your being unwittingly exposed to organisms or degradation products is most high when the solution is already cloudy due to the presence of an oil component (such as in a conditioner or styling product), which obscures your ability to observe growth at an early stage. Also, due to the presence of fragrance, one might not detect spoilage by smell in the early stages, either. By the time you are able to detect a problem, you could possibly have been applying a contaminated product for a few days.
My recommendation if you like to use diluted conditioner or other products on your hair is to do one of the following (and always with clean hands, boiled water, and a sterilized container):
- Make up a small amount of solution daily or every other day.
- Make up enough solution to last for one week and store it in the refrigerator when not in use.
- Make up enough solution to use for 1-2 weeks and add either natural or synthetic preservative drops to it in an amount specified in the literature. (Synthetic preservative mixtures, such as Kathon, can be purchased from a chemistry or cosmetic ingredients source, and natural preservatives such as grapefruit seed extract can be found at most health food stores). I would personally still store this mixture in the refrigerator when not in use and discard after a couple of weeks.
The same basic rules would apply when making a natural homemade concoction to treat your hair. If there will be water involved (in other words, it is not a pure oil product), then proper precautions regarding sterility and preservation should be taken to ensure your own safety.