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Why Preservatives Make a Better Mineral Makeup
By: Sam Dhatt
Posted: November 29, 2010, from the December 2010 issue of Skin Inc. magazine.
page 2 of 5
Unless the skin is being disinfected for surgery, cleansing with conventional products, including over-the-counter antibacterial soaps, basically lightens the bioload, but does not fully eradicate all bacteria. Luckily, few of these visitors are lethal. The normal, healthy body tolerates the presence of most bacteria, presuming that the immune system is robust. In fact, the good bacteria present actually defend the skin against pathogen invaders.
Skin is always in a state of bacterial activity, even in the most sterile of settings. The bacteria recolonize as soon as they are disturbed by cleansing, arriving from the air, from everything that is touched and from within the human body itself.
Four established groups of bacteria live on human skin: propionibacteria, corynebacteria, staphylococcus and streptococcus. Those last two groups should give you pause. Staphylococcus aureus and streptococcus mutans, pneumoniae and pyogenes are pathogens. Staphylococcus aureus is the leading cause of bacterial disease in humans, while streptococcus pneumoniae causes 95% of all bacterial pneumonia.
Other commonly found pathogens on the skin include Escherichia coli—E. coli—and Enterococcus faecalis, a component of human intestinal flora used by many European countries as a standard indicator of pollution by sewage, much the way E.coli counts are taken in U.S. waters to determine their safety for drinking and swimming. Human skin typically also swarms with Pseudomonas aeruginosa, Candida albicans, Aspergillus niger, Neisseria meningitidis, Haemophilus influenzae and several forms of Clostridium, all potentially aggressive microbes that are normally kept in check by healthy immunosuppression. Molds, fungi and yeasts are also present, to a smaller degree.
But do you really want to grow your own colonies of these bacteria in your makeup bag?