Updated: Nov 21, 2018
Products can get contaminated at any stage: during manufacturing site to usage. It is, therefore, important to make sure that microbial contamination will neither affect efficacy of the product nor will cause ill health. Preservatives are used as microbistatic or -cidal agents in food & cosmetic industry to keep products safe for use until shelf life.
What are parabens?
Parabens are esters of para-hydroxy benzoic acids (or sodium salts) and alcohols (ethyl, methyl, propyl & benzyl). The mechanism of action of parabens is not completely understood but possible pathways include:
1. Cellular metabolism
2. Penetrate through cell membranes
3. Hydrolysis of amino acids
Are parabens unsafe?
Parabens are used in personal care, pharmaceutical and food industry as they are one of the best preservatives (based on efficacy and economic aspects) but at the same time they have become questionable compounds due to reports of skin allergy and interference with metabolic functions. Their structure is like estrogens and some studies predict their role in development of breast cancer. Few studies also report that certain populations can be sensitive to parabens and may suffer from contact urticaria upon exposure. Parabens have been traced along with breast cancer cells in patients and in urine samples of large population in USA.
There are reports that parabens can penetrate to stratum corneum layer of skin, but they may not cause harm. Extensive studies were performed on animals as well as humans prove that they are safe at lower exposure doses.
There is ambiguity on safety of parabens as generous amount of data available proving their safety when used in lower concentrations and on normal healthy skin. Their extensive use and multiple exposure may warrant some caution.
The branched chain parabens like Iso butyl- derivatives have been banned by regulatory bodies. Parabens may be used in combinations (like ethyl- & propyl paraben) or as single compounds and are allowed up to 0.8 % total, with concentration of single compound not exceeding 0.4 %.