Clinical Insights

In recent years, I've noticed a shift in the questions patients ask about their skincare. Increasingly, they are looking beyond claims such as anti-ageing, hydrating or brightening and asking something much more fundamental: what exactly is in the products I use every day? These conversations are especially common among women planning a pregnancy, those undergoing IVF and fertility treatment, patients receiving chemotherapy, and individuals recovering from surgery. Others simply want to make more informed choices about the products they use, seeking greater ingredient transparency and a better understanding of what is often described as clean skincare. One topic that frequently arises is endocrine disruptors in skincare. While many cosmetic ingredients remain approved for use and scientific research continues to evolve, certain ingredients have attracted attention for their potential to interact with the body's hormonal systems. It is understandable that this has led many people to ask whether these ingredients deserve closer consideration, particularly during periods when their health or wellbeing may be a greater priority. Understanding the Endocrine System and Endocrine Disrupting Chemicals The endocrine system is one of the body's most important communication networks. Made up of glands such as the thyroid, adrenal glands, ovaries, testes and pancreas, it produces hormones—chemical messengers that travel through the bloodstream to regulate countless biological processes. Hormones influence far more than reproduction. They help regulate growth and development, metabolism, sleep, mood, stress responses, immune function and tissue repair. Every day, your body relies on these finely balanced chemical signals to keep its systems functioning as they should. As a plastic surgeon, I've always found the endocrine system remarkable because of how precisely it coordinates the body's response to change. Whether healing after surgery, adapting during pregnancy or responding to physical stress, hormones work continuously behind the scenes to maintain that delicate balance. What Are Endocrine Disrupting Chemicals? Endocrine disrupting chemicals (EDCs) are substances that have been shown, or are suspected, to interfere with the body's hormonal signalling. Rather than acting like toxins in the traditional sense, they may influence the way hormones are produced, transported, recognised or broken down within the body. Scientists have identified several ways in which certain endocrine disrupting chemicals may affect the endocrine system. Some may mimic naturally occurring hormones such as oestrogen, causing cells to respond as though the body's own hormones were present. Others may block hormone receptors, preventing natural hormones from carrying out their normal functions. Some may also alter hormone production, metabolism or elimination, potentially affecting the body's normal hormonal balance. It is important to recognise that endocrine disruption is an active and evolving field of scientific research. Not every chemical has the same biological activity, and any potential effects depend on many factors, including the specific ingredient, the amount of exposure, the duration of exposure, the route of absorption and an individual's own physiology. Many ingredients discussed in relation to endocrine disruption continue to be approved for cosmetic use by regulatory authorities around the world within established safety limits. Why Are Endocrine Disruptors in Skincare Receiving So Much Attention? Skincare products are unique because they are often used every day, sometimes several times a day, over many years. Although the amount of any single ingredient absorbed through the skin is typically low, researchers have increasingly explored the concept of cumulative exposure—the idea that we may encounter the same or similar chemicals from multiple sources throughout our daily lives, including cosmetics, personal care products, food packaging and the environment. This does not mean that using a skincare product containing one of these ingredients will cause harm. Rather, it has prompted scientists to better understand how repeated, long-term exposure to certain chemicals may contribute to overall exposure throughout a person's lifetime. As research continues to evolve, many individuals choose to take a precautionary approach by becoming more familiar with the ingredients in the products they use every day. "Patients often ask me whether an ingredient is "safe" or "unsafe", but the answer is rarely that simple. A more useful question is whether an ingredient serves an essential purpose, what the current evidence tells us about it, and whether equally effective alternatives exist. " — Dr Pearlie Tan, Founder of PPS Wellness Every ingredient should justify its place in a formulation. When equally effective alternatives are available, I believe it is reasonable to favour ingredients that offer the strongest safety profile and the fewest unanswered questions. When Ingredient Choices Matter Most -  - Women Trying to Conceive and Undergoing IVF - During Pregnancy - During Cancer Treatment - Recovery After Surgery - Health-Conscious Consumers   While research into endocrine disrupting chemicals continues to evolve, there are certain stages of life and medical situations where people naturally become more mindful of the products they use. During these times, many individuals begin looking beyond marketing claims and pay closer attention to ingredient labels, seeking greater transparency and reassurance about what they apply to their skin. Women Trying to Conceive and Undergoing IVF For many women, preparing for pregnancy is a time of heightened awareness about health and wellbeing. Nutrition, exercise and lifestyle habits often come under closer scrutiny, and skincare is no exception. It is increasingly common for women trying to conceive or undergoing fertility treatment to seek information about fertility-safe skincare and to better understand the ingredients in the products they use every day. During Pregnancy Pregnancy brings profound hormonal and physiological changes, making many expectant mothers more conscious of the products they use. Questions about pregnancy-safe skincare are among the most common concerns raised during this period, particularly as women become more aware of ingredient labels and the concept of cumulative exposure. During Cancer Treatment Cancer treatments such as chemotherapy and radiotherapy can significantly affect the skin, often leaving it drier, more sensitive and more easily irritated. During this time, many patients seek gentle skincare with fewer unnecessary ingredients, focusing on products that support the skin barrier and maintain comfort. Recovery After Surgery Following surgery or aesthetic procedures, the skin enters a complex healing process involving inflammation, tissue repair and remodelling. During recovery, patients often become more selective about the products they apply to healing skin, choosing formulations that are gentle, well tolerated and free from ingredients they consider unnecessary. Health-Conscious Consumers Interest in ingredient transparency is no longer limited to those facing a specific medical condition or life event. Increasingly, people are taking a more proactive approach to their health, seeking to understand the products they use just as they do the food they eat or the environments they live in. The growing interest in endocrine disrupting chemicals reflects a broader shift towards evidence-based, informed decision-making, with many people seeking to reduce unnecessary chemical exposure in their daily lives. Understanding Commonly Encountered Endocrine Disrupting Chemicals  Not all skincare ingredients have the same function, nor do they carry the same level of scientific interest. Among the thousands of ingredients used in cosmetic formulations, a relatively small number have been studied for their potential endocrine activity. It is important to remember that the presence of an ingredient does not automatically mean a product is unsafe. Many of these ingredients remain approved for cosmetic use within established concentration limits set by regulatory authorities. However, because scientific understanding continues to evolve, they remain the subject of ongoing research and discussion. The following endocrine disrupting chemicals are among the most commonly encountered in skincare products. Ingredient Group Why It's Used Why It's Being Studied What to Look for on Labels Parabens Preservatives that prevent microbial growth and extend shelf life. Certain parabens have demonstrated weak oestrogen-like activity in laboratory studies. Methylparaben, Propylparaben, Butylparaben, Ethylparaben Phthalates Used in some fragrance formulations and as solvents or fixatives. Certain phthalates have been studied for potential effects on reproductive and hormonal signalling. Diethyl Phthalate (DEP), Dibutyl Phthalate (DBP)*, or potentially within Fragrance / Parfum formulations Benzophenones / Oxybenzone UV filters used in sunscreens and some cosmetics. Some have demonstrated potential endocrine activity in laboratory and animal studies. Oxybenzone / Benzophenone-3 (BP-3) BHA & BHT Antioxidants that help prevent oils and formulations from oxidising. Studied for potential endocrine effects, primarily based on laboratory and animal evidence. Butylated Hydroxyanisole (BHA), Butylated Hydroxytoluene (BHT) Important: The presence of one of these ingredients does not mean that a cosmetic product has been proven to cause endocrine disruption in humans. The strength of evidence varies considerably between chemicals, and many remain permitted for cosmetic use within regulatory limits. They are included here because of scientific research into their potential endocrine activity.  Parabens Parabens are preservatives that help prevent the growth of bacteria, mould and yeast in cosmetic products. They have been used for decades because they are highly effective at extending shelf life and maintaining product safety. Common examples include: Methylparaben Ethylparaben Propylparaben Butylparaben Why are they being studied? Certain parabens have demonstrated weak oestrogen-like activity in laboratory studies, meaning they may bind to oestrogen receptors under experimental conditions. This has prompted researchers to investigate whether long-term exposure could have biological effects, particularly when combined with exposure from multiple sources.¹³ Current evidence suggests that the oestrogenic activity of parabens is significantly weaker than that of the body's naturally occurring oestrogen. However, questions remain regarding cumulative exposure and the potential effects of prolonged use, particularly for ingredients such as propylparaben and butylparaben.¹³ What should consumers know? Many regulatory authorities continue to permit parabens in cosmetic products within specified concentration limits, while some manufacturers have chosen to formulate products without them in response to evolving consumer preferences and ongoing scientific research.⁴ Phthalates Phthalates are a family of chemicals commonly used to improve flexibility in plastics and to help fragrances last longer in some personal care products. Why are they being studied? Certain phthalates have been associated with endocrine and reproductive effects in laboratory and epidemiological studies, leading many jurisdictions to restrict or prohibit their use in cosmetics.¹³⁴ What should consumers know? Not all phthalates are used in cosmetics, and regulations differ around the world. Increasingly, manufacturers offer phthalate-free products for consumers who prefer to minimise exposure.⁴ Benzophenones (Including Oxybenzone) Benzophenones are ultraviolet (UV) filters used to protect products and the skin from damage caused by sunlight. Oxybenzone is one of the best-known members of this group. Why are they being studied? Laboratory and animal studies have suggested that oxybenzone may demonstrate endocrine activity, and researchers have confirmed that it can be absorbed through the skin. However, there is currently no conclusive evidence that normal use of approved sunscreen products causes endocrine disorders in humans.¹³⁴ Beyond human health, researchers have been closely studying oxybenzone's impact on ocean life. When swimmers wear sunscreen in the ocean or wash it off in the shower, the chemical flows into marine habitats. Laboratory studies show that even low concentrations of oxybenzone can exacerbate coral bleaching by lowering corals' tolerance to warm temperatures. It has also been shown to damage coral DNA, cause severe deformities in young coral larvae, and act as an endocrine disruptor in marine life—impairing reproduction in fish, sea urchins, and algae.  What should consumers know? Sun protection remains one of the most effective ways to reduce premature skin ageing and lower the risk of skin cancer. Individuals who prefer to avoid oxybenzone may choose sunscreens formulated with alternative UV filters, including mineral filters such as zinc oxide or titanium dioxide. BHA and BHT BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene) are antioxidants that help prevent oils and other ingredients from oxidising, improving product stability and shelf life. Why are they being studied? Questions about BHA and BHT arise largely from high-dose animal studies investigating their potential endocrine activity. Evidence relating to cosmetic use in humans remains limited, and both ingredients continue to be permitted within regulated concentration limits in many countries.¹³⁴ What should consumers know? For many consumers, avoiding BHA or BHT is a personal preference rather than a medical necessity. Those wishing to minimise exposure can choose formulations that use alternative stabilising ingredients. A Balanced Perspective   As a surgeon, I encourage patients to approach ingredient information with curiosity rather than fear. Cosmetic safety is rarely determined by a single ingredient in isolation. Instead, it depends on the formulation as a whole, the concentration of each ingredient, how the product is used and the quality of the scientific evidence supporting its safety. Dr Pearlie Tan, Founder of PPS Wellness   Ultimately, informed consumers are empowered consumers. By understanding why certain ingredients attract scientific attention, you can make choices that reflect your own health priorities, values and stage of life. Choosing Skincare with Confidence Navigating skincare ingredients can feel overwhelming, particularly when scientific studies, social media and marketing messages often appear to contradict one another. While ingredient awareness is valuable, it is equally important to view each ingredient within the context of the product as a whole rather than in isolation. One term that has gained significant popularity is clean skincare. Although widely used by brands and consumers alike, there is currently no universally accepted scientific or regulatory definition of what constitutes "clean" skincare. One company's definition may differ considerably from another's, making it important to look beyond marketing claims and understand the ingredients themselves. Rather than relying solely on labels such as natural, organic or clean, I encourage patients to develop the habit of reading ingredient lists. Becoming familiar with commonly discussed ingredient groups—such as parabens, phthalates, benzophenones and BHA or BHT—allows you to make decisions that are based on knowledge rather than assumptions. It is also worth remembering that skincare is only one source of potential exposure to environmental chemicals. The products we use every day, the food we eat, food packaging, household items and our surroundings all contribute to our overall exposure. For this reason, many researchers now consider the concept of cumulative exposure, rather than focusing on a single product or ingredient in isolation. Conclusion The science surrounding endocrine disrupting chemicals continues to evolve, and researchers are constantly improving our understanding of how different substances interact with the human body. While many cosmetic ingredients remain approved for use within established safety limits, ongoing research helps us make better-informed decisions about the products we choose every day. My hope is not that every reader reaches the same conclusion, but that every reader feels empowered to ask thoughtful questions, understand the available evidence and make skincare choices that reflect their own health priorities. Informed decisions, guided by evidence and personal circumstances, are ultimately the foundation of confident and responsible skincare. Medical Disclaimer This article is intended for educational purposes only and reflects current scientific understanding at the time of writing. Research into endocrine disrupting chemicals continues to evolve, and scientific recommendations may change as new evidence emerges. The information provided should not be considered a substitute for personalised medical advice. Individuals who are pregnant, undergoing fertility treatment, receiving cancer therapy or managing other medical conditions should consult their healthcare professional regarding products that are appropriate for their individual circumstances. References Endocrine Society. Endocrine-Disrupting Chemicals: Position Statement. Diamanti-Kandarakis E, et al. Endocrine-Disrupting Chemicals: An Endocrine Society Scientific Statement. Endocrine Reviews. Tomar C, et al. Endocrine-disrupting chemicals in cosmetics: mechanistic insights and their impact on human and skin health. Scientific Committee on Consumer Safety (SCCS). Scientific opinions on parabens, benzophenone-3 (oxybenzone), BHA and related cosmetic ingredients.