Nobody likes to use preservatives. They donít help your skin or make you look younger, but preservatives are a necessary part of skin care formulations to prevent the multiplication of bacteria and mold in the product. If it were just a matter of throwing away a half-used product because there is some mold growing in it, we would not bother using them. However, it is more important than that. Even when you start with a perfectly clean product, spores and nasty bugs capable of causing very dangerous infections are floating in the air and could grow in the product unless the correct preservative, or mixture of preservatives, is included. So we use preservatives in our products to give us the peace of mind that our products should not harbor these microbial contaminants.
There has been a lot of bad press regarding parabens, and we feel pressed to come to their defense. Why? Because the arguments against parabens are bogus when the "evidence" is examined. Parabens have some estrogenic activity, but so do thousands of chemicals which we consume daily in our food. What matters is how strong the estrogenic activity is that a chemical has. In this case, strength is measured by the concentration of the putative analog required to displace the natural ligand, in this case estrogen. If you need very high concentrations of the estrogen-like chemical to dislodge the estrogen from the receptor, then the activity is very low and unlikely to be of significance in real life. This is what happens with parabens: they have very low affinity for the estrogen receptor.
Parabens have a long record of safety. They are non-allergenic, effective at very low concentrations, and they donít contribute a smell to the finished product. Smell is one of the problems of natural preservatives containing a mixture of extracts from oregano, rosemary, and more. The smell can be a overpowering (at least to my nose), and several of the extracts are allergenic. In the words of Dennis Sasseville, "the history of preservatives goes back to the 1930s, and ironically, the parabens, which the industry has sought to replace with 'safer' alternatives, are still the most frequently used biocides in cosmetics and appear to be far less sensitizing than most of the newer agents."
We (people who do like parabens) may eventually lose the "media war," as more people are convinced to avoid parabens. In this case, the general public will suffer because there are no good substitutes for parabens that will work for all products. Because preservatives are essential to keep skin care products safe, the result will be new preservatives coming to the market without enough testing. Then, in two decades, or even sooner, we may start seeing side effects from unproven preservatives.
It is worth mentioning that preservatives are just part of the equation. It is important to start with a clean product, i.e. to limit the bacterial and fungal presence as much as possible. It has been shown that the concentration of parabens required to inhibit fungal growth depends on the initial concentration of the organisms. In short, if you are planning to make a product, work clean! Disinfect everything you will use with rubbing alcohol and let it air dry, do not blow on the utensils. Then, add the preservative at the time of preparation, NOT as an afterthought one week after making the product.
At this time, we are using Leucidal.