Are Parabens really dangerous?

What are Parabens?
Parabens are a group of substances commonly employed as preservatives, mainly in personal care products, pharmaceuticals, and food. Parabens are derived from a chemical called para hydroxyl benzoic acid that occurs naturally in foods like strawberries, grapes, olives, blueberries, etc. Parabens are powerful preservatives. Cosmetic chemists use parabens in their formulations because they have no perceptible odor or taste, are effectively pH neutral, and do not discolor or harden.Methylparaben, ethylparaben, propylparaben, and butylparaben are the most commonly used independently and in combination with each other or other biocides. Methylparaben and propylparaben are most used, at concentrations of 0.4% or less and frequently much lower. Parabens are evaluated as non-mutagenic.

Without preservation, cosmetic products, and pharmaceuticals rapidly become contaminated with mold, fungi, and bacteria, resulting in spoilage and increased infection risk. The cleaner the manufacturing process and site, the less preservation required. Particularly problematic microbes are the gram-positive Staphylococcus aureus and the gram-negative Escherichia coli. Product preservation is an absolute necessity. Despite the misguided apprehension about and public fear of preservatives being “bad for you” or “not natural,” parabens have been classified as generally regarded as safe by the US Food and Drug Administration (FDA).

To enhance cosmetic properties, promote cosmetic efficacy, and produce more viable products, many cosmetics contain chemical additives, such as parabens. However, recent studies have cautioned that exposure to parabens may have harmful consequences on human health. Therefore, the safety of parabens for use as preservatives in cosmetics has come into controversy, and as a result, consumer demand for paraben-free products is widely increasing.

Why Paraben Phobia?
Many people fear parabens because of the claims made by various cosmetic companies and unscientific sources.

What did they claim?

• Parabens have the potential endocrine-disrupting ability.
• Parabens are carcinogenic and can result in breast cancer.
• Parabens harm your reproductive system.
• Parabens accumulate in the body.

Are the Above Claims True?
Parabens are not DANGEROUS….

Due to these claims Parabens have been continuously evaluated by the Food And Drug Administration (FDA) on a very strict basis. American cancer society, as well as FDA, concluded that there is no evidence that parabens are associated with cancer. Studies and reach papers also show that they don’t accumulate within human tissues. So, there is no reason to worry.

Are Paraben Alternatives Safer?
Other than parabens, the companies still have to put preservatives in the product. These preservatives tend to be more problematic with sensitive skin people. A paraben-free product often contains formaldehyde releasers which have more chances of giving allergies. Parabens are comparatively low-risk and safer preservatives for allergy-prone skin. From the angle of cosmetic companies, it is a marketing gimmick to sell you the product.

Physicochemical Properties and Metabolism

Parabens are homologous esters of p-hydroxybenzoic acid and represent an aromatic carboxylic acid containing a carboxyl group bonded directly to a benzene ring; a hydroxy group is present on position 4 with varying alkyl radicals as a side chain. Parabens, in general, are stable and nonvolatile; absorbed via the gastrointestinal tract and, to a degree, percutaneously; hydrolyzed to p-hydroxybenzoic acid, and conjugated with rapid urinary excretion. There is no solid evidence of accumulation within body tissues or organs, although detectable tissue and organ levels of indeterminate duration have been reported. One study has shown that parabens weakly interact with human serum albumin, thus suggesting that they are present to some degree in free form in plasma and available to reach or, theoretically, even accumulate in internal organs and tissues. Notwithstanding, parabens have not been proven to be carcinogenic or cytotoxic. Parabens are white, odorless, and crystalline and exhibit adequate water solubility to achieve the preservative activity. Increasing oil and organic solvent solubility is seen with increasing alkyl chain length (the same increase of chain length decreases water solubility and therefore the desired preservation activity). They are used in cosmetics, pharmaceuticals, and foods, but a strong, undesirable metallic taste occurs at concentrations of more than 0.08%, which (along with the understandable desire to minimize systemic exposure) results in limiting concentration used in foods. They are biodegradable by several nonspecific enzymes in nature, a fact that would suggest a potential environmental benefit in their use.

Antimicrobial Activity
On the macroscopic level, the mechanism of antibacterial action of parabens is linked to the membrane with disruption of the lipid bilayer, thereby interfering with bacterial membrane transport processes and perhaps causing the leakage of intracellular constituents.

The paraben family has excellent coverage against fungi and gram-positive bacteria. They are more effective against fungi than bacteria, and antibacterial activity is most effective against gram-positive organisms. Evidence of antimicrobial activity for commonly used parabens shows broad inhibition of E. coli, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans, with higher inhibition of staphylococcal species, particularly S. aureus.

Combinations of parabens are often found in final formulations, depending on solubility differentials, desired shelf life, and spectrum of activity. Evidence exists for improved antimicrobial efficacy with the use of lower concentrations of multiple parabens. Methylparaben and ethylparaben are the 2 most frequently paired Paraben biocidal activity increases with the length of the hydrocarbon alkyl chain, while solubility simultaneously drastically decreases. This is another rationale behind using parabens in combination. The issue of solubility of individual parabens, when used in combination, is complex. Propylparaben exhibits a peculiar solubility behavior in aqueous solution, with approximately 50% decreased solubility in mixtures also containing ethylparaben, a finding substantiated by solubility experiments on tertiary and quaternary combinations of parabens.

Because coverage against gram-negative bacteria is limited, a second non-paraben biocide is often added to the final formulations. Phenoxyethanol is the most commonly found synergistic biocide, but formaldehyde-releasing biocides and isothiazolinones are also frequently used.These combination biocides often allow effective preservation with lower concentrations of all preservative components.

References;
1. NCBI