Breast cancer is on the rise worldwide, and research increasingly points toward the often-overlooked role of environmental chemicals like triclosan as key contributors to this escalating health crisis.
Chemicals are pervasive in daily life, from the plastics used to store your food to the ingredients in your personal care products, and the pollutants filling your air and water. Many of these substances, often unseen, mimic or disrupt your body’s delicate hormonal balance and interfere with essential biological processes, laying the groundwork for breast cancer to take hold and progress.
Triclosan Is a Key Culprit in Breast Cancer
A study published in the journal Scientific Reports explored the links between common endocrine-disrupting chemicals (EDCs) — specifically phenols and parabens — and the development of breast cancer in women.1 The study used extensive data from the National Health and Nutrition Examination Survey (NHANES), collected between 2005 and 2014.
The researchers examined urine samples from 4,455 women, quantifying levels of various phenols, including bisphenol A (BPA), triclosan and benzophenone-3, and parabens, such as methyl, ethyl, propyl and butyl paraben.
Among these chemicals, triclosan emerged as a key focus. The researchers found that women in the second quartile of triclosan exposure faced a 2.33 times greater risk and those in the third quartile had a 1.94 times greater risk of developing breast cancer when compared to women in the lowest exposure group.
Interestingly, the study revealed a complex, nonlinear relationship between triclosan exposure and breast cancer risk, specifically an inverted U-shaped curve. This pattern indicates that as triclosan exposure initially increases, the risk of breast cancer also rises, but then, at even higher exposure levels, the risk appears to plateau or slightly recede, though it remains elevated compared to the lowest exposure group.
Overweight women had a stronger association between triclosan exposure and breast cancer risk. Similarly, women under the age of 60, as well as White women, also had a more pronounced connection. While other phenols and parabens were not linked to an overall increased risk of breast cancer in this study, ethyl and butyl paraben exposure were found to increase breast cancer risk specifically among lean women.
Study Reveals Mechanisms Behind Triclosan’s Breast Cancer Link
A 2023 study published in Frontiers in Public Health adds more fuel to the fire regarding triclosan’s dangers, particularly its link to breast cancer.2 Researchers looked at 302 women with breast cancer and compared them to 302 healthy women. They found a clear connection between higher levels of triclosan in the urine and an increased risk of breast cancer. The paper then explains how triclosan is causing this increased risk.
The researchers focused on oxidative stress, which is an imbalance of free radicals and antioxidants in your body. Oxidative stress damages your cells, including your DNA. The researchers measured several markers of oxidative stress and found that women with higher triclosan levels also had higher levels of these markers. This suggests that triclosan contributes to breast cancer by ramping up oxidative stress in the body.
The study also looked at telomeres, which are like protective caps on the ends of your chromosomes. Shorter telomeres have been linked to an increased risk of cancer. Interestingly, this study found a connection between triclosan exposure and longer telomeres, which, surprisingly, has also been linked to breast cancer risk. Triclosan’s influence on telomeres reveals another pathway by which it increases cancer risk.
Triclosan Is Found in Many Everyday Products
Triclosan is an antimicrobial agent incorporated into a vast range of everyday products, from antibacterial soaps and toothpastes to cosmetics and even clothing. Its primary function is to inhibit the growth of bacteria and fungi, extending product shelf life and appealing to consumer desires for cleanliness. However, this additive carries an undesirable trait: it’s readily absorbed into the human body.
Alarmingly, triclosan has been detected in human blood, urine and even breast milk, with widespread exposure across populations. In fact, 75% of the U.S. population has triclosan in their urine.3
This pervasive presence raises concerns, particularly given triclosan’s classification as an endocrine disruptor. Its chemical structure resembles thyroid hormones and several known endocrine disruptors like diethylstilbestrol (DES) and BPA, raising red flags for hormonal interference.
At low concentrations, triclosan appears to increase the growth of estrogen-sensitive breast cancer cells, suggesting it behaves like estrogen. Estrogen plays a complex role in breast cell growth and development. When this signaling is disrupted by chemicals like triclosan, it promotes abnormal cell proliferation, fueling the growth of tumors.
Further, triclosan has been linked to thyroid dysfunction, which itself has been associated with an increased risk of breast cancer. Beyond breast cancer, concerns extend to other developmental and health issues, including smaller head circumference at birth, early breast development in girls and even the promotion of antibiotic resistance and allergies.4
Because triclosan is used in so many personal care products, it often ends up being washed down the drain after use. Triclosan persists through wastewater treatment and accumulates in sewage sludge. This sludge is often used as fertilizer, allowing triclosan to be absorbed by plants, including food crops, introducing this harmful chemical into the food chain.
Early-Life Exposure to Chemicals Increases Breast Cancer Risk Later in Life
In a review published in Environmental Research, numerous epidemiological studies — research that tracks disease patterns in populations — were evaluated against established biological knowledge of how various chemicals interact with the human body at the cellular level.5 By merging these two streams of evidence — population trends and biological understanding — the review achieves a powerful perspective on the environmental chemical-breast cancer link.
The in-depth review found that early life exposures to certain environmental chemicals are particularly concerning for breast cancer risk later in life. Exposure during key windows of development — in utero, during infancy and throughout puberty — has lasting effects and increases vulnerability to breast cancer decades later.
The review specifically pinpoints persistent and pervasive chemicals like DDT and dioxins, along with perfluorooctane-sulfonamide (PFOSA), as posing significant risks when exposure occurs early in life.
Early-life exposure to endocrine disruptors like DDT and dioxins has particularly devastating effects on mammary gland development. Since these chemicals mimic or block natural hormones, it sends confusing signals to developing breast cells, altering their normal growth patterns and ultimately increasing cancer susceptibility. Beyond endocrine disruption, the review details other mechanisms at play.
Polycyclic aromatic hydrocarbons, or PAHs, and air pollution are highlighted as significant risk factors, particularly through the mechanism of DNA damage. PAHs, produced by burning fossil fuels and found in vehicle exhaust and industrial emissions, and components of general air pollution directly damage DNA, the very blueprint of your cells. This DNA damage, if not properly repaired, leads to mutations that drive cancer development.
Other widely used chemicals in consumer products were also named in the review. For instance, BPA, an endocrine disruptor with estrogenic activity, and phthalates and nonylphenols also exhibit endocrine-disrupting properties and have been linked to altered mammary gland development in animal models. Hair dyes and straighteners contain aromatic amines and formaldehyde, respectively, both of which have raised carcinogenicity concerns.
Per- and polyfluoroalkyl substances, commonly known as PFAS, are persistent chemicals with evidence of mammary gland effects and links to cancer. Flame retardants, including PBDEs, also show evidence of endocrine disruption and altered mammary gland development in animal studies.
The review reinforces the conclusion that environmental chemicals are not merely bystanders but active players in the development of breast cancer. It is not just about one or two isolated chemicals; it’s about the complex mixture of exposures you face daily and the cumulative impact these exposures have over your lifetime, especially when exposure occurs during important periods of development.
Proactive Steps to Reduce Your Chemical Exposure
While the risks posed by environmental chemicals is significant, remember that you’re not powerless. You can take meaningful steps to reduce your exposure and lessen your risk of breast cancer and other related health problems. It starts with making informed choices in your daily life and being proactive about your health. Every small change you make to reduce your chemical burden contributes to a healthier you.
1. Scrutinize your personal care products — Personal care products are a common source of triclosan, phthalates and nonylphenols. Start reading labels and opt for products specifically labeled “phthalate-free,” “triclosan-free” and “nonylphenol-free.” In addition, switch to simpler products with fewer ingredients, focusing on natural and organic options whenever possible. Your skin is absorbent, so what you put on your body matters.
2. Avoid antimicrobial products — Avoid “antimicrobial” soaps, toothpastes and other products claiming to be antimicrobial and containing triclosan or 5-chloro-2-(2,4-dichlorophenoxy)phenol — another name for triclosan. Wash your hands with plain soap and water. Antibacterial soaps are no more effective than plain soap for killing germs for everyday activities.
3. Peel your carrots and other root vegetables, or buy organic — Vegetables (especially the outer layer of roots) may be contaminated if sewage sludge is used as a fertilizer.6 Sewage sludge is not allowed in organic farming, so choosing organic produce is wise when possible.
4. Improve your indoor air quality — The air you breathe daily in your home is likely polluted with PAHs, flame retardants and other chemicals. Ensure your home is well-ventilated by opening windows regularly to circulate fresh air and reduce the build-up of indoor pollutants.
Vacuum and dust frequently to minimize dust, which is a significant source of triclosan, flame retardants and other chemicals. An air purifier with a HEPA filter is also a worthwhile investment to further cleanse your indoor air.
5. Consider natural progesterone for estrogen balance — If you’re concerned about the cumulative effects of xenoestrogens — estrogen-mimicking chemicals like triclosan — on your hormonal balance, consider natural progesterone. Natural progesterone works as an estrogen antagonist and helps mitigate some of the negative effects of excessive estrogen in your body.
Editor’s Note: This article is a reprint. It was originally published here: Articles