Endocrine Disrupting Chemicals

What is an endocrine disruptor?

An endocrine disruptor is any agent capable of interfering with our endocrine system, which is responsible for producing and regulating hormones. While the term can encompass non-chemical stressors, such as artificial light at night, certain types of radiation, or dietary components with hormonal activity (e.g., phytoestrogens in soy), it is most commonly used in reference to endocrine-disrupting chemicals (EDCs). An EDC is a chemical substance that alters endocrine function.

A chemical substance may either mimic the action of a natural hormone, thereby triggering similar reactions, or block the hormone receptors of cells, preventing the hormone from acting. In addition, EDCs can influence the synthesis, transport, metabolism and excretion of hormones, thus altering their concentration in the body.

Sources of EDCs

EDCs do not constitute a single chemical family, but rather a very broad set of substances capable of interfering with the hormonal system. Thousands have been identified, and they can enter the body by ingestion (diet and drinking water), inhalation or skin contact, or even reach the foetus or baby via the placenta or breast milk.

1. Food packaging and containers: Certain endocrine-disrupting chemicals migrate from food contact materials into food and beverages. These include bisphenols such as BPA and BPS, phthalates used as plasticisers, and per- and polyfluoroalkyl substances (PFAS) found in grease-resistant packaging, can linings, and non-stick cookware. Migration may increase with heat, repeated use, or food acidity. Exposure occurs primarily through ingestion. PFAS are known as ‘forever chemicals’ because they do not degrade in the environment and some can remain in the human body for approximately 5-10 years.
2. Pesticides and agriculture: Agricultural chemicals used in crop production and livestock farming include herbicides (e.g., atrazine), organophosphate insecticides (e.g., chlorpyrifos), legacy pesticides such as DDT, and certain PFAS used in pesticide formulations. Residues may be detected in fruit, vegetables, grains, animal feed, and animal-derived products. Exposure is mainly dietary, although occupational inhalation and dermal exposure may also occur. Persistence varies widely, with some compounds remaining in soil and water for decades.
3. Personal care and cosmetics: EDCs are incorporated into cosmetics and personal care products to serve preservative, antimicrobial, fragrance-stabilising, or UV-filtering functions. Common examples include phenols (such as some bisphenol derivatives), parabens, phthalates, and triclosan. Exposure occurs primarily via dermal absorption and is often chronic due to daily use. Dermal exposure can partially bypass first-pass liver metabolism, potentially increasing systemic bioavailability.
4. Household products and building materials: EDCs are present in indoor environments through consumer goods and construction materials. Phthalates are used in vinyl flooring and furnishings; polybrominated diphenyl ethers (PBDEs) are flame retardants found in electronics and furniture; and PFAS are used in stain-resistant textiles and coatings. These substances accumulate in indoor dust and air, leading to inhalation, ingestion (especially in children), and dermal exposure. Many are persistent and bioaccumulative.
5. Industrial and environmental contamination: Industrial activities have released persistent pollutants into air, soil, and water. These include polychlorinated biphenyls (PCBs), dioxins, heavy metals such as mercury, cadmium, and lead, and PFAS. They bioaccumulate in the food chain, particularly in animal fats and seafood. Exposure is mixed (dietary and respiratory), and some of these substances have long biological half-lives, meaning that it can take a long time for the body to eliminate them.
6. Pharmaceuticals and synthetic hormones: Certain medicinal products can act as endocrine disruptors when they are used outside of their intended therapeutic context. These include synthetic steroid hormones (e.g., ethinylestradiol used in oral contraceptives), progestins, androgens, as well as non-steroidal estrogens (e.g., diethylstilbestrol). Exposure can occur through therapeutic use, occupational handling or low-level environmental contamination.

Examples of endocrine disrupting chemicals

Health effects of endocrine disrupting chemicals

Endocrine disrupting chemicals alter the normal functioning of hormones, which regulate essential processes such as growth, metabolism, reproduction and brain development.

Although exposure is usually at low doses, its effect may be especially relevant when it occurs continuously or at critical stages of development, such as pregnancy or the first months of life. Another particularly vulnerable stage is pre-pubertal childhood; in this context, exposure to EDCs has been linked to an earlier onset of puberty. Additionally, research shows that some EDCs have a u-shaped response curve, meaning that they can have significant negative health effects at even very low doses.

Hormonal alterations may affect multiple systems. They have been associated with reproductive problems and fertility, changes in childhood growth, increased risk of obesity, diabetes and metabolic syndrome, as well as alterations in neurodevelopment. They may also influence the immune system, lung function or liver function and, in some cases, hormone-dependent tumours.

Some highly persistent substances remain in the body and the environment for years, meaning their effects may be long-lasting. Thus, the main health risk is not immediate poisoning but the silent modification of biological processes that may increase the probability of disease in the long term. And for those that are processed quickly by the body, the constant, daily exposure can have more immediate disruptive effects to everyday hormone functions.

There is no need to panic, as our health is not determined solely by exposure to endocrine disruptors. However, adopting and maintaining a healthy lifestyle remains essential. You can reduce EDC exposure by following certain guidelines, such as buying fewer synthetic materials or opting for glass or stainless steel food containers instead of plastic ones.