First, let’s spotlight the culprits that can dry out your skin: ethyl (also known as denatured, or SD, alcohol and ethanol) and benzyl. Note that methyl and isopropyl alcohol should never be seen in skin care, because they’re so harsh.

On the other hand, fatty alcohols are gems in skin care. These alcohols help formulas transform into silky-smooth products. They are:

• Cetyl alcohol, an emollient that comes from coconut oil. It’s often added as a stabilizer to cosmetic emulsions, such as: baby lotions, hand creams, foundation, lipstick, shampoo, mascara, deodorant, nail polish remover and cream blush.
• Stearyl alcohol, also derived from coconut oil, and can be used in place of cetyl alcohol in order to obtain a firmer formula. You’ll find stearyl alcohol in creams, lubricants, depilatories and conditioners.
• Cetearyl alcohol, an emulsifying wax that’s regularly used to soften ointments or other thick formulas. Widely found in permanent hair color, cleansers, face creams (especially for dry skin), eye makeup, lipstick and sunblock.
• Lanolin alcohol, the sebum extracted from sheep’s wool. It’s another excellent emulsifier that’s used in moisturizers, sunscreen, self-tanners, shaving cream and cosmetics.

However, some have charged that SLS is a carcinogen. At one point, a series of e-mails were circulating, warning that prolonged use of SLS would cause cancer. Despite these so-called warnings, SLS is neither a carcinogen nor dangerous. Experts agree that when used in minimal amounts, SLS is safe for your skin. In fact, according to the American Cancer Society, SLS and its compounds are not known carcinogens.

Research shows that the only real concerns are eye irritation and dry skin. For example, in a study published in the Journal of the American Academy of Dermatology, researchers applied SLS to the forearm and upper back of 10 women for 24 hours. Results revealed that the amount of water that normally evaporated from the skin’s surface increased, leaving the SLS-treated areas drier than the surrounding skin.

So individuals with sensitive or dry skin might want to avoid products with SLS. But anyone with normal or oily skin doesn’t need to worry about using SLS on a daily basis.

Mineral oil. Derived from petroleum and easily produced in mass quantities, mineral oil is relatively cheap and widely used across every sector of the skincare market. Although this ingredient is generally considered safe for cosmetic use, in recent years there’s been a backlash against mineral oil, prompting many myths. These include: Mineral oil is a known carcinogen; it clogs pores and causes acne; and dries out the skin.

However, the mineral oil you find in your skin care and cosmetics is highly refined, regulated by the Food and Drug Administration (FDA) and has been extensively studied. And the consensus is that mineral oil is not a carcinogen. Mineral oil might encourage breakouts in some people, mainly those with oily and acne-prone skin. But, for most of us, mineral oil is just fine. Its reputation for depleting dry skin of moisture is especially contradictory: Mineral oil is an occlusive agent, meaning that it improves the skin’s barrier function. This prevents moisture from leaving the skin. So, not surprisingly, it’s commonly used in many moisturizers.

Triclosan. This microbial agent is often found in antibacterial and acne-fighting products because of its ability to fight bacteria. It appears to be an effective ingredient in skin care, though studies have shown that washing your hands with soap and water is just as effective in killing germs as triclosan products. Some health advocates, however, question its safety.

In one study, the Environmental Protection Agency’s (EPA) Cancer Assessment Review Committee found a higher risk for adenomas and carcinomas in rats, though it didn’t find an association between triclosan and cancer among mice or hamsters, reports MedPage Today. Whether triclosan causes cancer in other animals and humans hasn’t been studied.

In addition, according to the EPA, triclosan is a pesticide that has negative effects on our environment, especially when exposed to ultraviolet light, which converts triclosan into dioxins (environmental pollutants). Interaction with tap water also could be toxic for the skin, especially water with high concentrations of chlorine.

Not everyone agrees about triclosan's harmful impact. Wayne Swofford, Ph.D., vice president of research and development at Microban International, tells The New York Times, "There are at least six peer-reviewed, published studies showing that you don't get resistant strains." He adds that there's an "infinitesimal" amount of triclosan in the environment. Also inconsequential, he says, is the combination of triclosan and chlorine in water.

Parabens. This group of popular preservatives, including methyl, ethyl, propyl and butyl, is one of the most controversial ingredients in the skincare industry. The biggest debate over parabens has been their supposed link to breast cancer. A 2004 study, published in the Journal of Toxicology, found parabens in breast tumors. But the study didn’t find that parabens cause cancer or that prolonged exposure to parabens is harmful.

The FDA considers parabens safe. In 1984, the Cosmetic Ingredient Review (CIR), an industry-sponsored organization, looked into the safety of parabens, concluding that they’re safe when used up to 25 percent. According to the FDA, parabens are used at 0.01 to 0.3 percent in skin care. In 2005, after reviewing its original conclusion, the FDA once again deemed parabens safe.

Parabens may irritate some skin types and conditions, including sensitive complexions and eczema.