In the pursuit of profits, however, cosmetics manufacturers aim for a long product shelf life: the longer a product can sit on a shelf, the easier it is for them to make money. The means of preservation is rarely considered beyond the obvious concern about whether the ingredient will cause immediate irritation. Sly manufacturers know that you won't buy a product that burns or stings. You will buy a product, however, that doesn't cause noticeable discomfort—especially if you are unaware that the preservative might cause much more sinister long-term effects.
And some of the most common preservatives (because they are the cheapest ones) may cause the most damage. Parabens including butyl, methyl, ethyl, propyl, isopropyl and isobutylpropyl parabens are easily absorbed into the skin. They also have been found in human breast tissue. They are false estrogens or xenoestrogens (pronounced "zeno-estrogens"), meaning that they trick the body into responding to them as if they were natural estrogens. These estrogen mimics cause hormone imbalances, and have been linked to reproductive cancers.
These paraben, urea and formaldehyde derivatives are also known to age skin and cause allergic reaction. Many are under investigation as cancer causing. Some also contain halogenated compounds, which will have the prefix -Brom, Iod, Fluor or Chlor. These accumulate in fat tissue and cannot be metabolized.
Please be sure to avoid any product listing any of these when the product also contains an ingredient with the prefix DEA,TEA, OR MEA. The combination leads to a process called nitrosation,(see:toxic ingredients) which can lead to cancer.
These chemical names are pretty scary. Do you want to find them in your cosmetics, skincare, deodorants and shampoos—and accumulating in your body? I don't. The bottom line is that your cosmetics don't have to last forever. Alternative, healthy preservatives designed to keep a product contaminant-free are available.
Just because cosmetics companies are willing to wager your health for their profits doesn't mean that you have to play along.