The following list contains 10 ingredients commonly found in skincare products that should be avoided.

Courtesy of eek the cat, Flickr Creative Commons

1. Nanoparticles

The use of nanoparticles in personal care products started with sunscreens. Titanium dioxide and zinc oxide have always been considered safer than chemical alternatives used in sunscreens and just as effective, but the public didn’t like the white coating left on their skin after application. As a result of this marketing obstacle, the sunscreen industry began nano-sizing or reducing the size of these particles so they would be more transparent. Nanotechnology is the science used to shrink chemical particles to 100 nanometers wide, roughly 1/100,000 of the thickness of a piece of paper. A nanoparticle is a particle smaller than 100 nanometers or 100 billionth of a meter. Their small size allows them to enter cells and potentially produce toxic effects. Besides sunscreens, nanoparticles are now showing up in make-up and anti-aging skincare products.

Terms associated with nanoparticles include: micronized, microspheres, microsoles, and fullerenes. FDA regulations currently do not require skin care companies to list nanoparticles on their labels. Dr. Samuel Epstein has been quoted as saying that “If you have to single out the most hazardous development in the whole field of cosmetics and personal care products, I’d put nanoparticles on the top of the list.” Further he said in a 2010 interview with Dr. Mercola:

“Nanoparticles, because of their ultramicroscopic size, readily penetrate the skin, can invade underlying blood vessels, get into the general blood stream, and produce distant toxic effects.”

” . . . the evidence which we’ve accumulated so far, is largely restricted to the fact that they [nano particles] get into your bloodstream and reach organs throughout your body.

“And as far as the brain is concerned, we have actual evidence of entry into the brain and producing toxic effects — lesions, small lesions, toxic effects in the brain.”

Smaller than blood vessels, nanoparticles are able to penetrate the skin far more deeply and faster than regular chemicals. “Invisible” zinc, used in sunscreens to avoid the white appearance of the cream, is created by using this technology.

In Sept. 2011, research at Brown University found that carbon nanoparticles can mimic asbestos properties, possibly leading to similar DNA damage as asbestos exposure.

As of June 2010, the FDA has known that these particles may actually accelerate the growth of skin cancer cells. Zinc oxide nanoparticles can kill important brain stem cells in mice and are toxic to animal colon cells even in small doses. Titanium dixoide nanoparticles injected into pregnant mice produced gene changes.

The FDA says that “Nanoparticles may present different safety concerns than their normal-sized counterparts.” It should be obvious that if the physiological size of something is changed, its reactions and behaviors also will be changed.

Additionally, these particles are washed off of our bodies and into our water systems and are damaging aquatic ecosystems. They are negatively affecting and destroying micro-organisms in our environment.

2. Oxybenzone

Oxybenzone is a chemical broad-spectrum sunscreen ingredient. Broad spectrum means it protects skin from both UVA and UVB ultraviolet sunrays. Its primary function is as a photostabilizer, absorbing harmful ultraviolet light rays through chemical reactions to sunlight. Some research shows it can be absorbed through the skin, although this research is controversial. The Environmental Working Group (EWG) and other toxicology experts report that oxybenzone is an endocrine (hormone) disruptor and their studies show it can be linked to cell damage and skin cancer. Sweden has banned its use.

Also oxybenzone has poor skin tolerance, often producing allergenic reactions and actually has a low absorption rate of UVA ray absorption. (UVB stops sunburn; UVA stops the skin cancer- causing rays.)

3. Polyethylene Glycol (PEG)

PEG’s (polyethylene glycol) are petroleum-based compounds used as product thickeners, solvents, softeners, and moisture carriers. They maybe contaminated with measureable amounts of a chemical called ethelene oxide (a known skin carcinogen) and 1,4 dioxane a by-product of a petrochemical process called ethyoxylation. Ethelene oxide can harm the nervous system. The California Environmental Protection Agency has classified ethelene oxide as a developmental toxicant based on evidence that it may interfere with human development. The Environmental Protection Agency classifies 1,4 dioxane as a possible human carcinogen. The presence of 1,4 dioxane even in trace amounts is cause for concern because it accumulates in the body. Its presence is linked with liver and bladder cancer in animals.The National Toxicology Programs’ Eighth Annual Report identifies PEG’s as possible carcinogens because they contain small amounts of ethelene oxide and potentially 1,4 dioxane.

PEG’s can have a manufacturing process called “stripping” to remove 1,4 dioxane but there is no easy way for consumers to know if this has been done. PEG names include: PEG-8, PEG-40 glycerol cocoate, PEG-6 and PEG-150.

4. Phthalates

Phthalates are known as “plasticizers” and are compounds used in the production of plastics to make them soft and pliable. They are also used in many cosmetics, particularly in fragrances and in some cases to make alcohol unfit for oral consumption. They may be labeled as “denatured alcohol.”

Their use in personal care products is to help products cling to the skin and increase longevity as in the case of helping fragrances to last longer. Phthalates on ingredient listings can be called “fragrance,” especially in perfume ingredient lists.

The compounds of phthalates bind specifically to estrogen receptors in our bodies and are considered “endocrine-disrupting chemicals.”

Recent studies have found these chemicals can alter genital development, create infertility, decrease sperm count, and increase the risk of testicular cancer in men and endometriosis in women. Phthalates from plastic bottles can leach into shampoos and other personal care products. They end up in our water systems and are washed down our drains and have been found to negatively impact marine life.

Other products often containing phthalates include hair gels, hairspray, shampoo/conditioner, soaps, perfumes, deodorants, nail polish, air fresheners and most things that come in soft plastic bottles.

5. Parabens

Parabens are synthetic preservatives used in cosmetics, foods, and pharmaceuticals. Their use is to allow skincare products to remain stable and stop the growth of harmful bacteria, fungus, and mold. Their use is to prolong the shelf life of a product. Scientific names include methylparaben, ethylparaben, propylparaben, and butylparaben.

Parabens are derived from para-hydroxybenzoic acid and have displayed the ability to slightly mimic the hormone estrogen and potentially disrupt the functioning of our endocrine system. The concern is that they are in such widespread use. In 2004 a study done at the University of Reading in the UK found parabens present in breast tumors (primarily methylparaben); however they were not able to determine if the parabens were the cause of the tumors. Cornell University (2011) reports that ongoing exposure to parabens can increase the risk of breast cancer as they have been shown to accumulate in fat cells, including breast tissue. Further studies have shown that methylparaben applied to the skin can react with UVB rays leading to increased skin aging and DNA damage. There are much safer preservatives on the market now, such as leucidal (made from fermented radishes) that are equally potent.

6. Propylene Glycol

Propylene Glycol is an alcohol derived from petroleum. It is used to dissolve natural extracts, attract water to increase moisturizing benefits of a product and help stabilize cosmetic formulations.

Although this ingredient has been described as having highly moisturizing properties, studies show the opposite. They show that propylene glycol partially dissolves the intercelluar cement of the stratum corneum , resulting in completely drying out the skin, making it more vulnerable to damage. Because propylene glycol is also used to enhance ingredient penetration, it can allow harmful ingredients to be absorbed more readily. This potentially increases the likelihood of allergic reactions and skin irritation.

This ingredient is often associated with brake and hydraulic fluids plus antifreeze. This is because there are different grades of this ingredient currently in use; one being commercial and the other, cosmetic. There is no way to communicate this grade difference on a label or for the consumer to be sure of which grade has been incorporated into their skin care product .

7. Phenoxyethanol

Phenoxyethanol is a common personal care preservative. It is an effective bactericide and has recently been widely used to replace parabens, especially in natural products. Phenoxyethanol has been found to be toxic to the body even in small doses.

In order to create it, the known skin carcinogen, ethylene oxide is combined with a phenol (a chemical compound which is also considered a carcinogen). The process of creating phenoxyethanol may (depending on each manufacturer’s production methods) produce the dangerous by- product called 1,4 dioxane. The EPA has established 1,4 dioxane is a probable human carcinogen. The FDA describes it as being able to depress the nervous system and may cause vomiting and diarrhea. The product’s Material Safety Data Sheet says that it is harmful if inhaled or swallowed or absorbed through the skin and that it can cause reproductive damage. The Chemical Toxicity Database lists that phenoxyethanol may cause central nervous system depression, kidney damage, skin irritation, headaches, dizziness, nausea and drowsiness. If inhaled it may cause respiratory and digestive tract irritation. Japan has banned the use of it in all cosmetics.

8. Fragrance

Synthetic fragrances are in thousands of personal care products, candles, and air fresheners. These scents can have as many as 200 chemical ingredients per aroma. There is no way to know what chemicals have been used because the FDA only requires manufacturers to list them as “Fragrance.” Often these fragrances are considered trade secrets by a manufacturer and their ingredient information is considered private information protected by law. Over 95 percent of synthetic fragrances are derived from petroleum. Some of the toxic ingredients used in synthetic fragrances include benzone derivatives such as phthalates (read above for more about this ingredient), formaldehyde, napthalene, xylene, toluenes, and aldehydes. These toxins are related to cancer, birth defects, central nervous system disorders, neurotoxicity, and allergic reactions. A study done in 2001 by the EPA found synthetic fragrances to contain hormone disruptors linked to abnormal cell reproduction.

Often products marketed as “unscented” or “fragrance free” contain a synthetic fragrance along with a “masking agent” that prevents the brain from perceiving fragrance.

Synthetic musk is of particular concern for the environment. Musk compounds are persistent in the environment and accumulate in the fat cells of aquatic organisms. Once musk compounds that have not been absorbed by our bodies have been washed off of our bodies, they enter into our water systems. Measureable amounts of synthetic musk have been found in the fish of the Great Lakes Region as well as in the sediment of the area.

9. Dimethicone AKA Polydimethylsiloxane (PDMS)

Dimethicone is a synthetic oil made from two different types of silicon polymers, D4 and D5. It is used primarily as a skin and hair conditioner. Manufacturers like it because it adds a gliding feel to lotions and creams. It also forms a lasting barrier on the skin that can fill in fine lines and wrinkles. The downsides to this ingredient are many. Silicone and its derived ingredients are occlusive, meaning they don’t let oxygen through. Dimethicone reduces normal and necessary skin functioning. The artificial coating of dimethicone on the outside of skin interferes with the skin’s natural ability to eliminate toxins coming out of the body. Recent studies show that prolonged exposure of the skin to its own sweat, because of occlusive substances like dimethicone, can cause skin irritation and impair cell development.

The European Union has found D4 to be an endocrine disruptor based on evidence it interferes with human hormone function and as a possible reproductive toxicant that may impair human fertility. Lab animal experiments using high levels of D5 have caused uterine tumors and harm to the reproductive and immune systems. D5 also showed an ability to influence neurotransmitters in the nervous system.

Dimethicone is not biodegradable. In Canada this ingredient has been shown to be persistent in the environment and to accumulate in aquatic organisms. Environment Canada and Health Canada have proposed adding D4 and D5 to the “List of Toxic Substances” and to limit the quantity of D4 and D5 in personal care products.

10. Genetic-Engineered Biosynthetic Ingredients

With the advent of GMO ingredients showing up in food, a new technology is entering the cosmetic industry, genetic engineered ingredients. According to NYR Natural News in February 2014, “Cosmetic companies are investing in extreme GMO technology to create novel ingredients.”

“According to a recent story in Genetic Engineering News, L’Oreal has signed a deal with a company called Evolva to develop novel biosynthetic ingredient that will have broad applications in the cosmetics industry.

The two companies are going to use fermentation technology developed by Evolva to produce and optimize yeast strains for production of the ingredient. The “ingredient” is as yet unidentified but Luc Aguilar, global head of L’Oréal’s biotechnologies department, said in a statement that the firm believes this platform “could end in new cosmetic ingredients bringing a real breakthrough for our customers.”

Most health concerns around GMOs have to do with putting them in our bodies. Putting them on our bodies is largely an unknown quantity. Because the details have not been revealed, it is impossible to say what the health impact may be.

L’Oreal is not the only cosmetic company investing in synthetic biology. Johnson & Johnson is also involved in developing hair and beauty products using this technology.

Evolva, in collaboration with a company called International Flavors and Fragrances, is also involved in the development of a vanilla essence made with synthetic biology. In response, the environmental group Friends of the Earth is actively campaigning against the product and asking food companies not to use it.

What is synthetic biology?

Synthetic biology, or synbio, is a new form of genetic engineering. Instead of using existing DNA from plants or animals synthetic biology involves scientists creating entirely new DNA sequences in the lab and using them to create new synthetic life forms or splicing this DNA into naturally occurring DNA.

It is a new science, the products of which have had no safety testing. Being manmade, sybio products are fully patentable and have the full protection of the law and, in theory at least, are able to freely enter the marketplace. Cosmetics and food are considered two of the most attractive markets for synthetic biologists.