Introduction: The Conscious Skincare Journey
Navigating the world of skincare can feel like deciphering a complex scientific code. Aisles are lined with brightly colored bottles boasting miraculous results, and ingredient lists are often a labyrinth of unpronounceable chemical names. In an era where consumers are increasingly mindful of what they put in and on their bodies, understanding the contents of our skincare products has never been more critical. This guide is designed to demystify that process, moving beyond fear-mongering to provide an evidence-based, rational approach to selecting products.
The goal is not to induce panic or suggest that every chemical is inherently harmful—after all, water is a chemical, and many synthetic compounds are both safe and highly effective. Instead, the purpose is to empower you with knowledge about specific ingredients that have been linked to potential health risks, skin irritation, environmental damage, or simply offer little to no benefit for their cost. By learning to identify these components, you can make more informed, conscious choices that align with your personal health priorities, skin type, and ethical values. This journey towards ingredient awareness is a proactive step in taking control of your skincare regimen, transforming it from a routine of hope into a practice of intentionality and self-care. We will delve into the science behind the concerns, explore why these ingredients are used despite the potential drawbacks, and identify safer, effective alternatives. Remember, knowledge is the most powerful skincare ingredient of all.
1. Parabens: The Preservative Predicament
Parabens are a class of synthetic compounds widely used as preservatives in cosmetics, skincare, pharmaceuticals, and even food products. Their primary function is to prevent the growth of harmful bacteria, mold, and yeast, thereby extending the shelf life of products and ensuring they remain safe for consumer use over time. Common parabens you might encounter on an ingredient list include methylparaben, ethylparaben, propylparaben, butylparaben, and isobutylparaben. The widespread use of parabens stems from their effectiveness, low cost, and long history in the industry. However, the controversy surrounding parabens erupted from a seminal 2004 study published in the Journal of Applied Toxicology, which detected parabens in human breast tumor tissue. This finding raised a red flag, suggesting a possible link between parabens and breast cancer. The hypothesis centers on parabens’ ability to mimic estrogen, the primary female sex hormone. As known xenoestrogens (foreign estrogens), parabens can bind to estrogen receptors on cells. While their estrogenic effect is considered much weaker than the body’s natural estrogen, chronic, low-level exposure from multiple sources is a point of concern for many endocrinologists and toxicologists. The theory is that this cumulative estrogenic activity could potentially disrupt the delicate balance of the endocrine system, which regulates growth, metabolism, and reproduction, and may play a role in the development of hormone-sensitive cancers. Furthermore, the fact that parabens are absorbed through the skin and can be detected in the blood, urine, and other bodily tissues indicates that they are not merely washed away but are systemically bioavailable. The cosmetic industry and regulatory bodies like the U.S. Food and Drug Administration (FDA) have maintained that parabens are safe at the low concentrations used in cosmetics, typically up to 0.4% for a single paraben and 0.8% for a mixture. They argue that the 2004 study did not prove parabens caused the tumors, only that they were present. Despite this, the public demand for paraben-free products has surged, leading many brands to reformulate. For consumers wishing to avoid parabens, the alternatives are plentiful. Many companies now use alternative preservative systems such as phenoxyethanol (though it has its own limitations), sodium benzoate, potassium sorbate, or natural preservatives like radish root ferment, leucidal liquid (derived from lactic acid bacteria), and certain essential oils. The decision to avoid parabens is a personal one, often rooted in the precautionary principle—the idea that it is better to err on the side of caution when definitive long-term human health impacts are not fully established, especially when safe and effective alternatives are readily available.
2. Phthalates: The Hidden Plasticizers
Phthalates, often referred to as “the everywhere chemical,” are a group of industrial chemicals used to make plastics more flexible and durable. Their application, however, extends far beyond vinyl flooring and shower curtains; they are pervasive in the beauty industry, though they are rarely listed explicitly on ingredient labels. In skincare and cosmetics, phthalates serve several functions. Most notably, they are used as solvents and plasticizers in nail polishes to prevent them from becoming brittle, and as vehicles for fragrance, helping scents to linger longer on the skin. This latter use is the primary way consumers encounter phthalates in skincare, as they can be hidden under the generic term “fragrance” or “parfum” on ingredient lists, thanks to trade secret laws that allow companies to keep their specific fragrance formulas confidential. The health concerns associated with phthalates are significant and center on their well-documented role as endocrine disruptors. Specifically, certain phthalates like diethyl phthalate (DEP), which is most commonly used in fragranced products, are known to interfere with the body’s androgen hormones, such as testosterone. This disruption is particularly concerning during critical developmental windows, such as pregnancy and early childhood. Prenatal exposure to phthalates has been linked to adverse outcomes in male infants, including anatomical changes in the genitalia associated with incomplete masculinization, a condition known as phthalate syndrome in animal studies. Furthermore, research has correlated phthalate exposure with increased risks of asthma, allergies, neurodevelopmental issues, and fertility problems in both men and women. Like parabens, phthalates do not persist in the body for a long time, but because exposure is continuous and ubiquitous from multiple sources (food packaging, dust, air fresheners, and personal care products), the body burden is constant. The evidence against phthalates is robust enough that they have been banned from children’s toys in many countries and are heavily restricted in the European Union for use in cosmetics. In the United States, the regulatory landscape is less stringent. To avoid phthalates, consumers must become diligent label readers. The most effective strategy is to choose products that are explicitly labeled “phthalate-free.” Since they are often hidden in fragrance, opting for products that are “fragrance-free” or that use natural, essential oil-based fragrances where the components are fully disclosed is another crucial step. Supporting brands that are transparent about their ingredients and committed to phthalate-free formulations is a powerful way to protect your health and drive industry-wide change.
3. Synthetic Fragrance and Parfum: The Secret Cocktail
The term “fragrance” or “parfum” on a skincare ingredient list represents one of the greatest mysteries and greatest sources of potential irritants and allergens in modern cosmetics. This single word can mask a complex cocktail of dozens, sometimes hundreds, of individual synthetic chemicals, none of which are required to be disclosed to the consumer. This loophole exists to protect a company’s “trade secret” formula, but it creates a significant problem for anyone with sensitive skin, allergies, or health concerns. From a skincare perspective, fragrance is a leading cause of allergic contact dermatitis, a condition characterized by redness, itching, swelling, and blistering. Reactions can be immediate or develop over time with repeated exposure, a process known as sensitization. Even if you have never experienced a reaction before, you can become sensitized to a fragrance component after multiple uses. The problem is compounded because you cannot identify which specific chemical is the culprit. Beyond skin irritation, the synthetic musks, phthalates, and volatile organic compounds (VOCs) commonly used in synthetic fragrances are associated with broader health issues. Many of these chemicals are respiratory irritants and can trigger asthma attacks. When applied to the skin, they can be absorbed into the bloodstream, and some, like the synthetic musks galaxolide and tonalide, have been found to bioaccumulate in human fat tissue and breast milk. There is ongoing research into their potential as endocrine disruptors. Furthermore, for individuals with conditions like rosacea or eczema, fragrance is almost universally a trigger that can lead to severe flare-ups. It is crucial to distinguish between synthetic fragrance and natural essential oils. While essential oils are derived from plants and can also be potent allergens for some individuals, they are specific, known compounds. A brand that uses essential oils for scent will typically list them (e.g., lavandula angustifolia (lavender) oil), allowing you to identify and avoid specific triggers. The safest choice for anyone, but especially for those with sensitive or reactive skin, is to choose products that are explicitly labeled “fragrance-free” or “unscented.” It is important to note that “unscented” can sometimes mean that masking fragrances have been added to neutralize the smell of other ingredients, so “fragrance-free” is the more reliable term. By eliminating synthetic fragrance from your skincare routine, you are not only reducing the risk of irritation and allergic reactions but also minimizing your exposure to a host of potentially harmful hidden chemicals.
4. Formaldehyde and Formaldehyde-Releasing Preservatives
Formaldehyde is a potent, colorless gas that is well-known as a human carcinogen, linked to nasopharyngeal cancer and leukemia by organizations like the International Agency for Research on Cancer (IARC). The idea of applying a known carcinogen to the skin is alarming, which is why you will rarely find pure formaldehyde listed as an ingredient in modern skincare. However, a more insidious threat exists in the form of formaldehyde-releasing preservatives. These are chemicals that, over time and under certain conditions (like heat or prolonged storage), slowly and continuously release minute amounts of formaldehyde to prevent bacterial growth in water-based products. Common formaldehyde-releasing agents include DMDM hydantoin, imidazolidinyl urea, diazolidinyl urea, quaternium-15, and bronopol (2-bromo-2-nitropropane-1,3-diol). These preservatives are effective and inexpensive, which is why they have been used for decades in a wide range of products, from shampoos and lotions to liquid baby soaps. The primary risk associated with these preservatives is twofold. First, there is the long-term, low-level exposure to formaldehyde, a carcinogen, through skin absorption and inhalation (particularly from sprays and lotions applied to the face and body). While the amount released from any single product is low and considered “safe” by regulatory standards, health advocates raise concerns about the cumulative effect of using multiple products containing these preservatives daily over a lifetime. This is known as the “cocktail effect.” Second, and more immediately concerning for many consumers, is that formaldehyde and its releasing agents are among the most common and potent allergens in the world. They are a leading cause of allergic contact dermatitis. Reactions can be severe, presenting as itchy, scaly, red rashes that can be misdiagnosed as eczema or psoriasis. For individuals already sensitized to formaldehyde (which can happen from exposure to other sources like building materials, household cleaners, or fabric finishes), using a product with a formaldehyde-releaser will almost certainly trigger a reaction. Due to consumer pressure and growing health concerns, many brands have phased out these preservatives. To avoid them, scan the ingredient list for the names mentioned above. Look for products preserved with alternative systems like phenoxyethanol (at safe concentrations), caprylyl glycol, or natural preservatives. The Environmental Working Group’s (EWG) Skin Deep database is a valuable resource for checking whether a product contains these ingredients. Choosing products from brands that have a clear “free-from” policy regarding formaldehyde-releasers is one of the most straightforward ways to minimize exposure to this unnecessary risk.
5. Sulfates: The Harsh Foaming Agents
Sulfates, most commonly Sodium Lauryl Sulfate (SLS) and its slightly milder cousin Sodium Laureth Sulfate (SLES), are surfactants—compounds that lower the surface tension between ingredients, acting as detergents, wetting agents, emulsifiers, and, most notably, foaming agents. They are the ingredients responsible for the rich, copious lather in shampoos, body washes, facial cleansers, and even toothpaste. This lather has been culturally ingrained as a sign of cleansing efficacy, but it often comes at a cost to skin and hair health. The primary issue with sulfates, particularly SLS, is their potency as degreasers. They are extremely effective at stripping away oil and dirt, but in doing so, they can also strip the skin and scalp of their natural, protective lipids (fats) and proteins. This disruption of the skin’s natural barrier function can lead to a cascade of problems. For the skin, this manifests as dryness, tightness, irritation, and flakiness. It can exacerbate conditions like eczema, rosacea, and psoriasis by compromising the skin’s first line of defense, allowing irritants to penetrate more easily and moisture to escape more rapidly—a process known as transepidermal water loss (TEWL). For those with sensitive skin, SLS can cause redness and inflammation. On the scalp, this stripping action can lead to dryness, itching, and increased sensitivity. Furthermore, because sulfates are such strong cleansers, they can cause color-treated hair to fade more quickly and make curly or frizz-prone hair more unmanageable by removing its natural moisture. The manufacturing process for SLES also raises a separate concern: it can be contaminated with 1,4-dioxane, a probable human carcinogen, which is a byproduct of the ethoxylation process. 1,4-dioxane is not listed on labels as it is a contaminant, not an ingredient. While many companies now use vacuum-stripping to remove this contaminant, it is not a universal practice. It is important to note that not everyone needs to avoid sulfates. Individuals with very oily, resilient skin and no sensitivity may tolerate them without issue. However, for anyone experiencing dryness, sensitivity, or inflammatory skin conditions, switching to sulfate-free cleansers is one of the most impactful changes they can make. sulfate-free alternatives use much gentler surfactants derived from coconut oil, amino acids, or other sources, such as decyl glucoside, cocamidopropyl betaine, or sodium cocoyl isethionate. These cleansers effectively remove dirt and impurities without compromising the skin’s barrier, often resulting in less tightness and irritation post-cleansing. The lather may be less dramatic, but the cleansing is no less effective, and the long-term benefits for skin health are substantial.
6. Mineral Oil: The Controversial Occlusive
Mineral oil is a highly refined byproduct of the petroleum industry, specifically derived from crude oil during the distillation process to produce gasoline and other petroleum products. In skincare, it is used as an occlusive agent, meaning it forms a physical barrier on the surface of the skin that prevents water loss. This makes it an effective, inexpensive, and stable moisturizing ingredient in everything from baby oils and body lotions to heavy-duty creams and ointments like Vaseline. Despite its widespread use and approval by regulatory bodies like the FDA as safe for topical application, mineral oil is the subject of significant controversy and is often avoided by consumers in the natural and clean beauty communities. The concerns surrounding mineral oil are multifaceted. First, there is the issue of its origin. For many, the idea of applying a petroleum-derived substance to the skin is unappealing, especially when plant-derived alternatives are available. This is largely an ethical or philosophical objection. Second, and more scientifically, the concern revolves around the purity of the mineral oil used. Mineral oil comes in different grades: industrial grade, which is not suitable for cosmetics and may contain harmful impurities, and cosmetic or pharmaceutical grade, which is highly refined and purified to remove these contaminants. The safety of mineral oil in skincare is contingent on it being of high purity. The third major concern is its comedogenic potential. Because mineral oil is a heavy occlusive, it can create a seal on the skin that, for some skin types, traps dead skin cells, bacteria, and sebum inside the pores. This can lead to clogged pores, blackheads, and acne breakouts, particularly for those with oily or acne-prone skin. While it is non-comedogenic for many, it is a common trigger for others. Furthermore, while it is excellent at preventing moisture loss, it does not actively add moisture or nutrients to the skin. It is functionally inert, meaning it doesn’t provide the skin with vitamins, antioxidants, or fatty acids that are beneficial for skin health and repair. For those seeking a more “nourishing” experience, plant-based oils like jojoba, squalane (from sugarcane or olives), argan, or rosehip oil are often preferred. These oils mimic the skin’s natural sebum, provide essential nutrients, and offer occlusive benefits without the same potential for clogging pores or the ethical concerns of a petroleum origin. Ultimately, the decision to use mineral oil is a personal one. Highly purified mineral oil is considered safe and can be a godsend for extremely dry, cracked skin that needs a powerful barrier repair agent. However, for those with acne-prone skin or who prefer bio-active, plant-derived ingredients, there are numerous effective and nourishing alternatives.
7. Chemical Sunscreen Filters: Oxybenzone and Octinoxate
Sunscreen is arguably the most crucial step in any skincare routine for preventing photoaging and reducing the risk of skin cancer. However, the specific active ingredients used to block ultraviolet (UV) radiation have come under intense scrutiny, particularly chemical filters like oxybenzone (benzophenone-3) and octinoxate (octyl methoxycinnamate). These chemicals work by absorbing UV radiation and converting it into heat, which is then released from the skin. While effective at preventing sunburn, a growing body of evidence highlights significant potential drawbacks for human health and the environment. From a health perspective, oxybenzone is the most controversial. It is a potent absorber of UVB and short-wave UVA rays, but it is also a known penetrant; studies have shown it can be absorbed through the skin in significant amounts, and it has been detected in urine, blood, and even breast milk. The core concern is its endocrine-disrupting activity. Research, primarily in animal and cell studies, has indicated that oxybenzone can mimic estrogen, potentially leading to hormonal imbalances. It has also been linked to allergic skin reactions and, in some studies, to a higher risk of endometriosis. Octinoxate, another common chemical filter, also shows evidence of endocrine disruption, with studies suggesting it can affect thyroid function and reproductive systems in animal models. The human health implications of these findings at typical exposure levels are still debated within the scientific community, but for many consumers, the precautionary principle applies. The environmental impact of these chemicals, however, is undeniable and has led to legislative action. When people swim in the ocean wearing sunscreens containing oxybenzone and octinoxate, these chemicals wash off and accumulate in the water. They have been proven to be highly toxic to coral reefs, even at minute concentrations. They contribute to coral bleaching, damage coral DNA, and disrupt the development of young coral, ultimately leading to the death of reefs. This environmental devastation has prompted places like Hawaii, Key West, and Palau to ban the sale of sunscreens containing oxybenzone and octinoxate. Fortunately, there are excellent alternatives. Mineral sunscreens, which use physical blockers like zinc oxide and titanium dioxide, are widely regarded as safer for both human health and the environment. These ingredients sit on top of the skin and reflect UV rays away like a mirror. Modern formulations have overcome the past issues of leaving a white cast, with many now using “micronized” or “nano” particles for a more cosmetically elegant finish. For comprehensive protection, look for “broad-spectrum” mineral sunscreens that contain zinc oxide, as it protects against both UVA and UVB rays effectively. By choosing reef-safe, mineral-based sunscreens, you can protect your skin without compromising your health or the planet’s ecosystems.
8. Polyethylene Glycols (PEGs)
Polyethylene Glycols, or PEGs, are petroleum-based compounds that are incredibly common in cosmetics. They function in a variety of ways: as thickeners, softeners, moisture-carriers, and penetration enhancers. Their versatility is why you’ll find them in everything from creamy lotions and serums to toothpaste and laxatives. PEGs themselves are a large family of compounds, and they are typically followed by a number (e.g., PEG-100 Stearate) that indicates their molecular weight, which affects their properties. The primary safety concern with PEGs is not necessarily the compound itself, but rather the potential for contamination during the manufacturing process. The production of PEGs involves ethoxylation, a process that uses ethylene oxide, a known human carcinogen. This process can result in PEGs being contaminated with two harmful substances: 1,4-dioxane (another probable carcinogen, as mentioned with SLES) and residual ethylene oxide. Both of these contaminants are not listed on ingredient labels. The concentration of these impurities depends on the degree of purification, and reputable manufacturers have processes to minimize them. However, because this is not tightly regulated or required to be disclosed, it creates uncertainty for consumers. A second concern, particularly for skincare, is PEGs’ function as penetration enhancers. By disrupting the skin’s surface barrier, they can increase the absorption of other ingredients in the formula. While this can be desirable for delivering beneficial actives like antioxidants or peptides, it can also increase the absorption of other, potentially harmful contaminants or ingredients you might wish to avoid, such as synthetic fragrance or preservatives. For individuals with compromised or damaged skin, this heightened permeability could lead to increased irritation or systemic exposure. While PEGs with a molecular weight above 500 are considered to have low skin penetration, the overall lack of transparency about purity is a valid reason for caution. For those seeking to avoid PEGs, the task involves carefully scanning ingredient lists for any word beginning with “PEG-” or “Polyethylene Glycol.” Alternatives are plentiful; many natural and clean beauty brands use plant-derived thickeners and emulsifiers like cetearyl alcohol (which can be derived from plants), xanthan gum, and acacia gum. While avoiding PEGs requires more label diligence, it is a feasible way to minimize potential exposure to carcinogenic contaminants and to choose products with more natural, plant-based formulation bases.
9. Ethanolamines: DEA, MEA, TEA
Ethanolamines are a group of chemicals that include diethanolamine (DEA), monoethanolamine (MEA), and triethanolamine (TEA). In cosmetics, they are primarily used as emulsifiers to ensure that oil and water-based ingredients mix properly, and as pH adjusters to maintain a product’s acidity or alkalinity for stability and skin comfort. You will often find them in creamy products like moisturizers, sunscreens, and foundations, as well as in cleansers for their foaming properties. The safety concerns for ethanolamines are similar to those for PEGs and are two-fold. First, the primary concern is the potential for these ingredients to react with other substances in the formula to form nitrosamines. Nitrosamines are a class of chemical compounds, many of which are potent carcinogens. This nitrosation process can occur either during the product’s shelf life or on the skin itself if it comes into contact with nitrites from other sources. While cosmetic manufacturers are supposed to use inhibitors to prevent nitrosamine formation, the risk cannot be entirely eliminated. The International Agency for Research on Cancer (IARC) has listed DEA as possibly carcinogenic to humans, based on animal studies where it caused liver and kidney cancers. While direct evidence in humans is lacking, the potential for carcinogenic nitrosamine formation is a significant red flag. The second concern is that these compounds are known skin and respiratory irritants, particularly for individuals with sensitive skin or conditions like eczema. They can cause contact dermatitis, dryness, and allergic reactions. Due to these health concerns, the European Union has banned DEA in cosmetics, and the use of DEA and its related compounds is restricted in Canada. In the United States, the FDA has issued guidance but not an outright ban. For consumers, identifying ethanolamines on an ingredient list is straightforward: look for DEA, MEA, or TEA, often in combination with another ingredient name, such as Cocamide DEA or Lauramide DEA. Avoiding these ingredients is a proactive step to reduce potential exposure to carcinogenic nitrosamines and to minimize the risk of skin irritation. Many modern formulations have moved away from these compounds, using safer, alternative emulsifiers and pH adjusters derived from coconut oil or other plant sources.
10. Triclosan and Triclocarban: The Antimicrobial Agents
Triclosan and triclocarban are powerful antimicrobial agents that were once ubiquitous in “antibacterial” soaps, hand sanitizers, body washes, and even some acne treatments and deodorants. Their function was to kill bacteria and other microbes on the skin. For decades, they were marketed as providing a superior level of cleanliness compared to regular soap. However, a significant body of research and subsequent regulatory action has led to a dramatic decline in their use, particularly in rinse-off products. The concerns are substantial. First, the U.S. Food and Drug Administration (FDA) concluded in 2016 that there was no evidence that antibacterial soaps containing triclosan were any more effective at preventing illness than washing with plain soap and water. This rendered the primary marketing claim—and the associated health risks—completely unnecessary. The risks are serious. The widespread use of triclosan is a major contributor to the growing global crisis of antibiotic-resistant bacteria, or “superbugs.” By constantly exposing bacteria to low doses of triclosan, we encourage the survival and proliferation of resistant strains, making it harder to treat serious infections. Second, like many other chemicals on this list, triclosan is a suspected endocrine disruptor. Animal studies have shown that it can interfere with thyroid hormone regulation, which is critical for metabolism, growth, and brain development. It may also impact estrogen and testosterone levels. Furthermore, when triclosan is washed down the drain, it does not break down easily and can accumulate in the environment. It has been detected in waterways and soil, and when exposed to sunlight in water, it can convert into dioxins, which are highly toxic environmental pollutants. Due to these overwhelming concerns, the FDA banned triclosan and triclocarban from over-the-counter consumer antiseptic wash products in 2017. However, they can still be found in some consumer products like certain toothpastes (where it is used to fight gingivitis), cosmetics, and kitchenware. To avoid them, check labels for “triclosan” or “triclocarban.” The best practice for hand hygiene remains washing with plain soap and water for at least 20 seconds. For situations where soap isn’t available, an alcohol-based hand sanitizer (with at least 60% alcohol) is a safe and effective alternative that does not carry the same risks of bacterial resistance or endocrine disruption.
11. Aluminum Salts: The Antiperspirant Debate
Aluminum salts, such as aluminum chlorohydrate and aluminum zirconium, are the active ingredients in antiperspirants (not to be confused with deodorants). They work by forming a temporary plug within the sweat ducts, which reduces the amount of perspiration that reaches the skin’s surface. Deodorants, on the other hand, work by masking odor with fragrance and neutralizing odor-causing bacteria; they do not contain aluminum and do not stop sweat. The controversy surrounding aluminum in antiperspirants is one of the most persistent in the realm of personal care, primarily due to its proposed link to breast cancer. The hypothesis suggests that aluminum, when applied to the underarm area close to the breast tissue, can be absorbed through the skin. This is plausible, especially if the skin is shaved or has minor nicks, which can enhance absorption. Once in the body, aluminum is known to have estrogen-like effects, and since estrogen can promote the growth of hormone-receptor-positive breast cancer cells, the theory is that aluminum could contribute to the development or progression of the disease. Additionally, some studies have pointed to a higher concentration of aluminum in the outer breast tissue near the underarm. However, and this is a critical point, major health organizations including the National Cancer Institute (NCI) and the American Cancer Society (ACS) have stated that there is no conclusive scientific evidence linking antiperspirant use with breast cancer. They note that the studies suggesting a link have been small or flawed in their methodology, and larger population-based studies have not found a connection. The absorption of aluminum through the skin is also believed to be minimal. Despite the lack of conclusive evidence, the concern remains for many, driven by the desire to minimize exposure to potentially harmful substances, especially in such a sensitive area. For those who are concerned, the alternatives are straightforward. Switching to a deodorant that does not contain aluminum is the simplest solution. These products will be labeled as “deodorant,” not “antiperspirant.” Many natural deodorants use ingredients like baking soda, arrowroot powder, and essential oils to absorb moisture and fight odor. It is important to note that there may be a transition period when switching, as your body adjusts to the change. The decision to avoid aluminum-based antiperspirants is a personal one, based on individual risk tolerance. While the current scientific consensus does not support a causal link to breast cancer, choosing an aluminum-free deodorant is a safe and effective option for those who prefer to follow the precautionary principle.
12. Butylated Hydroxyanisole (BHA) and Butylated Hydroxytoluene (BHT)
BHA and BHT are synthetic antioxidants that are used as preservatives in a vast array of products, from food and food packaging to rubber, petroleum products, and cosmetics. In skincare, their primary role is to prevent fats and oils in a formulation from becoming rancid due to oxidation, thereby extending the product’s shelf life. You will often find them in lipsticks, moisturizers, and other oil-based products. While they are effective stabilizers, their safety profile is a subject of ongoing debate and regulatory scrutiny. The core concern stems from their potential to act as endocrine disruptors. Studies in animals have shown that BHA can affect the thyroid gland and reproductive system. Both BHA and BHT have exhibited effects on hormone levels in various animal models. Furthermore, the International Agency for Research on Cancer (IARC) has classified BHA as “possibly carcinogenic to humans” (Group 2B), based on sufficient evidence of carcinogenicity in animal experiments, though evidence in humans is inadequate. BHT has also raised concerns, though the evidence is somewhat less conclusive than for BHA. It is important to contextualize this risk; the concentration used in cosmetics is typically very low. However, the issue of cumulative exposure is again relevant, as these chemicals are found in so many everyday products, from the cereal you eat to the lip balm you apply. For individuals with sensitive skin, BHA and BHT can also be irritants and have been known to cause allergic contact dermatitis. Due to these concerns, their use in cosmetics is restricted in the European Union. For consumers looking to avoid them, scanning the ingredient list for “BHA” (which may also be listed as butylated hydroxyanisole) and “BHT” (butylated hydroxytoluene) is essential. Many brands now use natural antioxidants as preservatives instead, such as tocopherol (Vitamin E), rosemary extract, or ascorbic acid (Vitamin C). These alternatives not only stabilize the product but can also provide additional skin benefits. Choosing products preserved with these natural antioxidants is a simple way to avoid the potential risks associated with synthetic BHA and BHT.
13. Coal Tar: A Legacy Ingredient
Coal tar is a thick, black liquid that is a byproduct of the coal carbonization process. It has a long history of use in skincare, primarily in products designed to treat serious skin conditions like psoriasis, seborrheic dermatitis, and dandruff due to its ability to slow down the rapid growth of skin cells and reduce itching and inflammation. You will find it in medicated shampoos, creams, and ointments, often listed as “coal tar solution,” “pix carbonis,” or simply “coal tar.” Despite its therapeutic efficacy, coal tar is one of the most concerning ingredients still legally allowed in cosmetics and over-the-counter drugs. The reason for this high level of concern is unequivocal: coal tar is a known human carcinogen. The International Agency for Research on Cancer (IARC) classifies it as a Group 1 carcinogen, the highest rating, meaning there is sufficient evidence that it causes cancer in humans. This classification is based on occupational studies showing that workers exposed to coal tar vapors and dusts, such as in the aluminum production and paving industries, have a significantly increased risk of skin, lung, bladder, and gastrointestinal cancers. While the concentration used in topical preparations is much lower, and the risk from intermittent use on small areas of skin is considered low by dermatologists, the principle of applying a known carcinogen to the skin, especially to skin that is often inflamed and potentially compromised, is alarming to many. Furthermore, coal tar is a potent sensitizer and can cause severe skin irritation, photosensitivity (increased sun sensitivity), and staining of skin and hair. Due to these risks, coal tar is banned from use in cosmetics in the European Union, though it is still permitted in pharmaceutical products. In the United States, it remains an approved OTC drug ingredient. For those seeking alternatives for scalp conditions like psoriasis or dandruff, there are effective options. Salicylic acid helps to exfoliate and remove scales, pyrithione zinc has antifungal and antibacterial properties, and selenium sulfide is effective against the yeast that can exacerbate dandruff. For body psoriasis, topical corticosteroids, Vitamin D analogs like calcipotriene, and modern biologic drugs are often preferred by dermatologists due to their efficacy and better safety profile. While coal tar may be a powerful, old-school treatment, its status as a known carcinogen makes it an ingredient that many consumers will understandably choose to avoid given the availability of safer alternatives.
Conclusion: Empowerment Through Ingredient Awareness
The journey through the landscape of potentially problematic skincare ingredients can feel overwhelming, but it is ultimately an exercise in empowerment. The objective is not to live in fear of every product on the shelf, but to become a conscious, informed consumer capable of making choices that align with your personal health values and skin’s needs. This guide has detailed a range of ingredients, from preservatives like parabens and formaldehyde-releasers to harsh surfactants like sulfates and controversial actives like chemical sunscreens. The common thread among them is that for each one, there are legitimate concerns—be it links to health issues, a high potential for irritation, or environmental harm—coupled with the existence of safer, effective alternatives. It is crucial to remember that skincare is not one-size-fits-all. An ingredient that causes a reaction in one person may be perfectly tolerated by another. The most important tool you have is your own power of observation. Pay attention to how your skin responds to products. If you experience persistent redness, itching, breakouts, or dryness, learning to decode the ingredient list can help you identify the potential culprit. Start by eliminating one category at a time, such as synthetic fragrances or sulfates, to see if your skin’s condition improves. Utilize resources like the Environmental Working Group’s Skin Deep database to research products before you buy. Support brands that prioritize transparency, safety, and sustainability. The movement towards cleaner, safer beauty is consumer-driven, and every purchase is a vote for the kind of products you want to see on the market. Ultimately, the goal of skincare is to nurture and protect your skin. By arming yourself with knowledge, you can move beyond marketing hype and build a routine that is not only effective but also safe and conscientious. Your skin is your body’s largest organ; treating it with care and respect by choosing ingredients that support its long-term health is one of the most profound acts of self-care you can practice.
SOURCES
Author. (Year). Title of the article. Title of the Journal, Volume(Issue), Page numbers.
Barr, L., Metaxas, G., Harbach, C. A. J., Savoy, L. A., & Darbre, P. D. (2012). Measurement of paraben concentrations in human breast tissue at serial locations across the breast from axilla to sternum. Journal of Applied Toxicology, 32(3), 219–232.
Darbre, P. D., & Harvey, P. W. (2008). Paraben esters: Review of recent studies of endocrine toxicity, absorption, esterase and human exposure, and discussion of potential human health risks. Journal of Applied Toxicology, 28(5), 561–578.
Dodge, L. E., Kelley, K. E., Williams, P. L., Williams, M. A., Hernández-Díaz, S., Missmer, S. A., & Hauser, R. (2015). Medications as a source of paraben exposure. Reproductive Toxicology, 52, 93–100.
Swan, S. H., Main, K. M., Liu, F., Stewart, S. L., Kruse, R. L., Calafat, A. M., Mao, C. S., Redmon, J. B., Ternand, C. L., Sullivan, S., & Teague, J. L. (2005). Decrease in anogenital distance among male infants with prenatal phthalate exposure. Environmental Health Perspectives, 113(8), 1056–1061.
Huang, P. C., Li, W. F., Liao, P. C., Sun, C. W., Tsai, E. M., & Wang, S. L. (2014). Risk for estrogen-dependent diseases in relation to phthalate exposure and polymorphisms of CYP17A1 and estrogen receptor genes. Environmental Science and Pollution Research, 21(24), 13964–13973.
Schettler, T. (2006). Human exposure to phthalates via consumer products. International Journal of Andrology, 29(1), 134–139.
Johansen, J. D., Frosch, P. J., & Lepoittevin, J. P. (2011). Contact Dermatitis (5th ed.). Springer.
Frosch, P. J., Johansen, J. D., & White, I. R. (2002). Fragrance contact allergy: A clinical review. American Journal of Clinical Dermatology, 3(11), 789–798.
Bridges, B. (2002). Fragrance: Emerging health and environmental concerns. Flavour and Fragrance Journal, 17(5), 361–371.
Dodson, R. E., Nishioka, M., Standley, L. J., Perovich, L. J., Brody, J. G., & Rudel, R. A. (2012). Endocrine disruptors and asthma-associated chemicals in consumer products. Environmental Health Perspectives, 120(7), 935–943.
International Agency for Research on Cancer. (2012). Chemical agents and related occupations: A review of human carcinogens. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 100F. World Health Organization.
de Groot, A. C., & Flyvholm, M. A. (2013). Formaldehyde and formaldehyde-releasers. In Patch Testing (pp. 305–334). Springer.
Flyvholm, M. A., & Menné, T. (1992). Allergic contact dermatitis from formaldehyde. A case study focusing on sources of formaldehyde exposure. Contact Dermatitis, 27(1), 27–36.
Lee, C. H., & Maibach, H. I. (1995). The sodium lauryl sulfate model: An overview. Contact Dermatitis, 33(1), 1–7.
Rhein, L. D., Simion, F. A., Hill, R. L., Cagan, R. H., Mattai, J., & Maibach, H. I. (1990). Human cutaneous response to a mixed surfactant system: Role of solution phenomena in controlling surfactant irritation. Dermatologica, 180(1), 18–23.
Black, R. E., Hurley, F. J., & Havery, D. C. (2001). Occurrence of 1,4-dioxane in cosmetic raw materials and finished cosmetic products. Journal of AOAC International, 84(3), 666–670.
Fiume, M. M., Bergfeld, W. F., Belsito, D. V., Hill, R. A., Klaassen, C. D., Liebler, D. C., Marks, J. G., Shank, R. C., Slaga, T. J., Snyder, P. W., & Andersen, F. A. (2012). Safety assessment of petrolatum and mineral oils as used in cosmetics. International Journal of Toxicology, 31(5), 445–460.
Kligman, A. M. (1996). The myth of lanolin allergy. Contact Dermatitis, 35(1), 1–7.
DiNardo, J. C., & Downs, C. A. (2018). Dermatological and environmental toxicological impact of the sunscreen ingredient oxybenzone/benzophenone-3. Journal of Cosmetic Dermatology, 17(1), 15–19.
Downs, C. A., Kramarsky-Winter, E., Segal, R., Fauth, J., Knutson, S., Bronstein, O., Ciner, F. R., Jeger, R., Lichtenfeld, Y., Woodley, C. M., Pennington, P., Cadenas, K., Kushmaro, A., & Loya, Y. (2016). Toxicopathological effects of the sunscreen UV filter, oxybenzone (benzophenone-3), on coral planulae and cultured primary cells and its environmental contamination in Hawaii and the U.S. Virgin Islands. Archives of Environmental Contamination and Toxicology, 70(2), 265–288.
Krause, M., Klit, A., Blomberg Jensen, M., Søeborg, T., Frederiksen, H., Schlumpf, M., Lichtensteiger, W., Skakkebaek, N. E., & Drzewiecki, K. T. (2012). Sunscreens: are they beneficial for health? An overview of endocrine disrupting properties of UV-filters. International Journal of Andrology, 35(3), 424–436.
Fiume, M. M., Heldreth, B. A., Bergfeld, W. F., Belsito, D. V., Hill, R. A., Klaassen, C. D., Liebler, D. C., Marks, J. G., Shank, R. C., Slaga, T. J., Snyder, P. W., & Andersen, F. A. (2016). Safety assessment of polyethylene glycols (PEGs) and their derivatives as used in cosmetic products. International Journal of Toxicology, 35(2), 5S-34S.
National Toxicology Program. (2016). Report on Carcinogens, Fourteenth Edition. U.S. Department of Health and Human Services, Public Health Service.
Andersen, F. A. (2006). Final amended report on the safety assessment of triethanolamine, diethanolamine, and monoethanolamine. International Journal of Toxicology, 25(2), 1–30.
Food and Drug Administration. (2016). Safety and Effectiveness of Consumer Antiseptics; Topical Antimicrobial Drug Products for Over-the-Counter Human Use. Final Rule. Federal Register, 81(172), 61106–61130.
Halden, R. U. (2010). Plastics and health risks. Annual Review of Public Health, 31, 179–194.
Weatherly, L. M., & Gosse, J. A. (2017). Triclosan exposure, transformation, and human health effects. Journal of Toxicology and Environmental Health, Part B, 20(8), 447–469.
McGrath, K. G. (2003). An earlier age of breast cancer diagnosis related to more frequent use of antiperspirants/deodorants and underarm shaving. European Journal of Cancer Prevention, 12(6), 479–485.
Mirick, D. K., Davis, S., & Thomas, D. B. (2002). Antiperspirant use and the risk of breast cancer. Journal of the National Cancer Institute, 94(20), 1578–1580.
Darbre, P. D. (2005). Aluminium, antiperspirants and breast cancer. Journal of Inorganic Biochemistry, 99(9), 1912–1919.
IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. (1999). Some chemicals that cause tumours of the kidney or urinary bladder in rodents and some other substances. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 73. World Health Organization.
Botterweck, A. A., Verhagen, H., Goldbohm, R. A., Kleinjans, J., & van den Brandt, P. A. (2000). Intake of butylated hydroxyanisole and butylated hydroxytoluene and stomach cancer risk: results from analyses in the Netherlands Cohort Study. Food and Chemical Toxicology, 38(7), 599–605.
International Agency for Research on Cancer. (2010). *Some non-heterocyclic polycyclic aromatic hydrocarbons and some related exposures. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 92*. World Health Organization.
HISTORY
Current Version
SEP, 24, 2025
Written By
BARIRA MEHMOOD