The Impact of Junk Science on R&D: A Review of the 'Dirty Dozen'

By: David C. Steinberg, Steinberg & Associates

Posted: September 29, 2010, from the October 2010 issue of Cosmetics & Toiletries.

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In addition, parabens do not easily penetrate the skin unless they are dissolved in a solvent that enhances skin penetration; however, since they typically are dissolved in water for their use, penetration into the skin from cosmetic products is almost impossible to achieve. Currently, the FDA database lists the following numbers of formulas as containing these preservatives: 13,434 with methylparaben; 4,869 with ethylparaben; 10,421 with propylparaben; 336 with isopropylparaben; 5,289 with butylparaben and 2,693 with isobutylparaben. While there are replacements for parabens in some formulations, there is not an easy drop-in replacement in every case. In addition, replacements typically are more expensive and have less safety data available.

PEG Compounds

The next items to look for, according to the report, are chemical propylene glycol and other related ingredients containing the letters eth (e.g., polyethylene glycol or PEG-60). The group notes that PEG (polyethylene glycol) compounds are widely used in cream bases in cosmetics. PEG (and its chemical cousin, propylene glycol) opens the skin’s pores, allowing harmful ingredients to penetrate more deeply. PEG and other “ethoxylated” ingredients (which usually have chemical names including the letters “eth”) may be contaminated with ethylene oxide and 1,4-dioxane. Both contaminants may cause cancer. Also, ethylene oxide may harm the nervous system and interfere with human development, and 1,4-dioxane is persistent. In other words, it doesn’t easily degrade and can remain in the environment long after it is rinsed down the shower drain.

Facts: First of all, as chemists generally know, PEGs are not chemical cousins to propylene glycol (PG); these are two different types of chemistries. PEGs are polymers while PG is a simple 3-carbon atom diol. There is only one PG, while according to the PCPC INCI dictionary there are over 1,200 PEG derivatives and 46 PEG polymers. The dictionary also lists more than 900 eth ingredients that are formed by ethoxylation. The writer of the foundation’s report failed to mention all the other ingredients made from ethylene oxide. Further, ethylene oxide reacts violently with water, which makes it nearly impossible to find ethylene oxide in cosmetic products. 1,4 Dioxane is a by-product of ethoxylation but the industry has learned to reduce it to trace levels and the FDA has found no issue with the presence of these trace amounts.¹⁷ Since there are more than 2,100 ingredients in this list, their frequency of use is not included here.

Petrolatum

The foundation report states that petrolatum or mineral oil jelly is used in a variety of moisturizers as a barrier to lock moisture into the skin. It is also reported to be used in hair care products to make hair shine. The report adds: petrolatum, a petrochemical, can be contaminated with cancer-causing polycyclic aromatic hydrocarbons (PAHs). The EU considers petrolatum a carcinogen and restricts its use in cosmetics.

Facts: This interpretation of the EU regulation is the worst this author has ever seen. The EU bans petrolatum except when the full refining history is known, and when it can be shown that the substance from which the material is produced is not a carcinogen.¹⁸ Petrolatum or petroleum jelly has been used for more than 100 years topically as a drug and cosmetic ingredient as well as a lubricant. The foundation report’s writer would be hard-pressed to find a single case of cancer reported to be caused by petrolatum. Further, no US or Canadian producer of petrolatum ever has been prohibited by the EU. Based on the FDA database, there are currently 2,267 registered formulas containing petrolatum. While some ingredient suppliers are offering substitutes for this material, again, they are typically more expensive and cannot be used as equivalents in all applications.

Siloxanes