A clear, honest look at hormone-disrupting chemicals, what peer-reviewed research has found, and what it means for everyday life.

There are things we have known for decades that still haven’t fully reached everyday conversation.

One of them is this: industrial chemicals that disrupt the hormonal system are present in our bodies — in our blood, our urine, our tissue — and a growing body of peer-reviewed research links them to declining reproductive health across the industrialised world.

This is not a fringe theory. It is published science, reviewed by independent researchers, in the world’s leading medical journals.

And it is worth understanding.

What the Endocrine System Does

The endocrine system is the body’s chemical communication network. Hormones — produced by the thyroid, adrenal glands, ovaries, testes, and other glands — travel through the bloodstream and regulate metabolism, sleep, mood, immune function, development, and reproduction.

Critically, hormones operate in extremely small concentrations. Even tiny changes in hormonal signalling can have significant effects on how the body functions.

This is why endocrine-disrupting chemicals (EDCs) are a particular concern — not because they are toxic in the way a poison is, but because they can interfere with hormonal communication at very low doses, and because exposure is lifelong and cumulative.

What the Research Has Found

The evidence base has grown substantially over the past two decades. Here is what peer-reviewed research consistently shows:

EDCs have been found in ovarian tissue and follicular fluid. A 2023 study published in Chemosphere, conducted at the Center for Reproductive Medicine at Peking University Third Hospital, measured 21 different EDCs — including parabens, phthalates, bisphenols, and PFAS — in the follicular fluid of women undergoing IVF treatment. The researchers found that higher levels of this chemical mixture were associated with a significantly increased likelihood of diminished ovarian reserve: the condition in which a woman has fewer and lower-quality eggs than expected for her age.

Female fertility is deteriorating in industrialised regions. A 2022 review published in Nature Reviews Endocrinology by researchers at the Copenhagen University Hospital, one of the world’s leading reproductive medicine centres, concluded that both male and female reproductive health is deteriorating in industrialised regions, and explicitly named endocrine-disrupting chemicals and pesticides as important environmental factors in this decline.

The global fertility rate is falling and chemicals are part of the picture. The International Federation of Fertility Societies published a consensus document in 2024 in Human Reproduction Update concluding that exposure to environmental pollutants, including endocrine-disrupting chemicals and pesticides, can be directly harmful to eggs and sperm. The document noted that male sperm concentration has been declining by approximately 1.4% per year and total sperm count by 1.6% per year — a trajectory that, if it continues, has profound implications for human reproduction.

A 2024 systematic review covering 14 epidemiological studies published between 2014 and 2024 found consistent associations between EDC exposure — specifically BPA, phthalates, parabens, and PFAS — and multiple reproductive problems, including impaired semen quality, decreased ovarian reserve, infertility, polycystic ovary syndrome, and poor outcomes in IVF.

Women are exposed to higher levels of certain EDCs than men. A 2024 review published in Frontiers in Public Health noted that women are often exposed to higher concentrations of phthalates than men, specifically through their greater use of personal care and cosmetic products. These phthalates — used as fragrance fixatives and plasticisers — have been shown to impair ovarian function and are found in products used daily by millions of women.

Where These Chemicals Come From

EDCs are not exotic substances found only in industrial settings. They are present in many products of everyday life.

Personal care and cosmetic products: certain preservatives, synthetic fragrances, and UV filters contain chemicals with hormonal activity. Parabens and phthalates are among the most studied, and both have been found in human tissue.

Plastics and food packaging: bisphenol A (BPA) and its replacements (BPS, BPF) are used in many plastic products and food containers. BPA has oestrogenic activity and has been detected in human blood and tissue in studies around the world.

PFAS (“forever chemicals”): used to make products water-resistant, stain-resistant, and non-stick. PFAS accumulate in the body over time and have been detected in ovarian tissue. Research links PFAS exposure to decreased ovarian reserve and poorer fertility outcomes.

Pesticides: many conventional pesticides have endocrine-disrupting properties. Exposure occurs through food, water, and indoor environments.

Synthetic fragrances: the word “fragrance” or “parfum” on an ingredient list can represent a mixture of many individual chemicals, including phthalates that are not separately disclosed.

The Problem of Cumulative Exposure

Perhaps the most important thing to understand is that this is not about any single chemical.

It is about lifelong, simultaneous exposure to a mixture of chemicals — from food, water, air, personal care products, and household materials — that are rarely tested together, and whose combined effects are poorly understood by regulators.

Traditional toxicology was built on the principle that “the dose makes the poison.” But this principle does not straightforwardly apply to endocrine disruptors, which can exert effects at very low doses, and whose effects may be more significant during certain developmental windows — in the womb, during puberty, during reproductive years.

Researchers are increasingly calling for regulatory systems that reflect this complexity, and for the precautionary principle to be applied more consistently to chemicals that interfere with hormonal systems.

Why This Matters and What Can Be Done

It is reasonable to feel frustrated by this information. Many of these chemicals were approved for widespread use under regulatory frameworks that did not adequately account for endocrine-disrupting effects, low-dose impacts, or cumulative exposure. Some have been in common use for decades.

The frustration is legitimate. But it is not a useful place to stay.

Because while we cannot control the full extent of our chemical environment, we can reduce our everyday exposure — particularly from the products we choose to use on our bodies and in our homes.

Fragrance is one of the most meaningful places to start. Choosing fragrance-free or naturally fragranced personal care products reduces exposure to undisclosed phthalates and other fragrance components.

Plastics in contact with food and drink: particularly when heated, are worth reconsidering. Glass, stainless steel, and ceramic are practical alternatives.

Personal care products: paying attention to ingredient lists, looking for products with transparent formulas, and choosing certified products where possible makes a real difference over time.

Organic produce: for the foods eaten most frequently, particularly those with higher pesticide residues, choosing organic reduces one meaningful source of EDC exposure
These steps do not eliminate all exposure. Nothing does. But together they represent a genuine and practical reduction in everyday chemical load and a more intentional relationship with the things we bring into our lives.

A Final Thought

The scientists who study endocrine disruptors are not alarmists. They are careful researchers working with peer-reviewed data. And many of them — including those who have found industrial chemicals in ovarian tissue and in the fluid surrounding developing eggs — have changed their own lives in response to what they have learned.

That is worth taking seriously.

Not with fear. Not with helplessness.

But with the kind of clear-eyed, informed attention that is the beginning of any meaningful change.

Research references used in this post:

• Tian et al. (2023). Mixed and single effects of endocrine disrupting chemicals in follicular fluid on likelihood of diminished ovarian reserve. Chemosphere, 330, 138727.
• Skakkebæk et al. (2022). Environmental factors in declining human fertility. Nature Reviews Endocrinology, 18, 139–157.
• Fauser et al. (2024). Declining global fertility rates and the implications for family planning and family building. Human Reproduction Update, 30(2), 153–173.
• Tricotteaux-Zarqaoui et al. (2024). Endocrine disruptor chemicals exposure and female fertility declining. Frontiers in Public Health, 12, 1466967.
• Shulhai et al. (2024). Which is the current knowledge on man-made endocrine-disrupting chemicals in follicular fluid? Frontiers in Endocrinology, 15, 1435121.

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