WHAT ARE ENDOCRINE DISRUPTING CHEMICALS?

Endocrine-disrupting chemicals (EDCs) are substances studied for their potential to interfere with hormonal signalling within the endocrine system. Research has explored associations between certain EDC exposures and changes in developmental, reproductive, neurological, and immune-related processes in both humans and wildlife.

EDCs include a broad range of natural and synthetic compounds, such as phytoestrogens, some pharmaceuticals, phthalates, dioxins, pesticides, polychlorinated biphenyls (PCBs), and plasticisers like bisphenol A (BPA) and bisphenol S (BPS). Potential sources of exposure discussed in the literature include some personal care products, cleaning agents, food packaging, plastics, canned foods, and thermal paper receipts.

Research in this area is ongoing, and awareness of potential exposure sources allows for informed, proportionate consideration as part of a broader view of health and wellbeing.

Here are some really frightening statistics. There are an estimated 50,000 chemicals in use today. Very few of these have been tested for their endocrine effects. It is estimated that 800-1000 are endocrine disruptors and only a small proportion of these have actually been tested. OMG. How is this even possible?

HOW DO THEY WORK?

Research has identified several theoretical and observed mechanisms through which endocrine-disrupting chemicals (EDCs) may interact with hormonal signalling pathways. These interactions are studied in laboratory, animal, and epidemiological research and help explain why EDCs are of ongoing scientific interest.

Rather than acting on a single hormone, EDCs are discussed in the literature as having the potential to interact with multiple points along the hormonal signalling cascade.

In research settings, endocrine-active chemicals have been described as having the capacity to:

  • Interact with hormone receptors by mimicking the structure of naturally occurring hormones — such as oestrogens, androgens, or thyroid hormones — which may influence how hormonal signals are interpreted by cells.
  • Occupy hormone receptors without activating them, which can interfere with normal hormone–receptor signalling.
  • Influence hormone metabolism, including pathways involved in hormone activation, transport, or breakdown, such as those occurring in the liver.
  • Alter hormonal signalling patterns, with studies describing effects that may increase, decrease, or modify normal hormone activity depending on timing, dose, and context.

These mechanisms are not mutually exclusive and are highly dependent on factors such as the specific chemical involved, the level and timing of exposure, and individual biological variability.

Understanding these proposed mechanisms helps provide context for ongoing research into environmental exposures and hormonal health, without assuming uniform effects across individuals.

SIDE EFFECTS

Endocrine-disrupting chemicals (EDCs) are a broad group of substances that have been studied for their ability to interact with hormonal signalling pathways. Research in this area has explored how EDC exposure may be associated with alterations in hormonal regulation relevant to reproductive, metabolic, neurological, and immune function.

In scientific and epidemiological studies, exposure to certain endocrine-active chemicals has been associated with changes in reproductive markers in both men and women, as well as with conditions that involve hormonal pathways, such as menstrual irregularities and fertility-related concerns. Research has also examined potential links between EDC exposure and a range of other health outcomes, although findings vary and continue to evolve.

Particular attention has been given to exposure during sensitive life stages. The prenatal and early postnatal periods are widely recognised in research as times when developing organ systems may be more susceptible to environmental influences, including endocrine-active compounds (National Institute of Environmental Health Sciences).

In 2013, the World Health Organization (WHO), in collaboration with the United Nations Environment Programme (UNEP), released a report highlighting the breadth of biological systems that may be affected by endocrine-disrupting chemicals. The report noted that these systems include those involved in reproductive development and function, metabolism, and neurological processes, and that disruptions observed in research settings have been linked with a range of health-related markers (WHO/UNEP, 2013).

This body of research has contributed to increased regulatory attention and ongoing investigation into environmental chemical exposures. Awareness of these findings allows individuals and health professionals to consider environmental factors as part of a broader, whole-person approach to health, without assuming direct causation at an individual level.

EXAMPLES OF ENDOCRINE DISRUPTORS

Phthalates

Phthalates are a group of industrial chemicals that have been widely used as plasticisers, particularly in polyvinyl chloride (PVC) products. They have also been used in a variety of consumer goods, including some personal care products, pharmaceuticals, paints, adhesives, and household materials (Frederiksen et al., 2007; Wittassek et al., 2011).

Common sources discussed in the literature include flexible plastics, vinyl flooring, wall coverings, furniture materials, shower curtains, packaging materials, medical tubing, and some cosmetics and personal care products. In personal care items, certain phthalates have historically been used as solvents or fixatives, particularly within fragrance formulations.

Human exposure to phthalates can occur through multiple pathways, including food contact materials, indoor dust, air, and direct use of personal care products (Wormuth et al., 2006; Janjua et al., 2008; Wittassek & Angerer, 2008).

Phthalates have been extensively studied for their potential to interact with endocrine pathways. Much of the concern around phthalates arises from animal and laboratory studies, where certain compounds have been shown to influence hormonal signalling and developmental processes under specific exposure conditions. Epidemiological studies in humans have explored associations between some phthalates — including diethyl phthalate (DEP) — and reproductive or fertility-related markers, although findings vary and research in this area continues to evolve.

Because of these findings, phthalates have been the subject of regulatory review and reformulation efforts in many countries, particularly in relation to products used during sensitive life stages.

Parabens

Parabens are used as antimicrobial preservatives in personal care products, cosmetics and pharmaceuticals. They are commonly found in deodorants, body washes, shampoos, facial cleansers & makeup products. The worst of this group include Methylparaben (MetP), ethylparaben (EthP) and propylparaben (ProP), used as food preservatives in confectionary and dried meat (Larsson et al, 2014). They are easily absorbed through the skin and the use of parabens has raised concern due to their weak oestrogenic activity confirmed in in vivo and in vitro studies (Larsson et al, 2014).

According to Campaign for Safe Cosmetics, “Parabens mimic oestrogen by binding to oestrogen receptors on cells. They also increase the expression of genes usually regulated by oestradiol (a natural form of oestrogen); these genes cause human breast cancer cells to grow and multiply in cellular studies ”

BPA/BPS

Bisphenol A (BPA) is a high-production-volume chemical that has been used in the manufacture of polycarbonate plastics and epoxy resins. These materials have historically been used in a range of products, including food and beverage can linings, plastic containers, thermal paper receipts, and some industrial applications.

Dietary intake is considered one of the primary sources of human exposure, as BPA can migrate from food packaging into food under certain conditions. Research examining canned food products has identified ongoing BPA use in some packaging, despite increasing regulatory scrutiny and reformulation efforts (Geens et al., 2012; Environmental Working Group, 2015).

BPA has been widely studied for its ability to interact with hormone receptors, particularly oestrogen receptors, and is commonly described in the scientific literature as an endocrine-active compound. Much of the data examining biological effects comes from animal and laboratory studies, where BPA exposure has been associated with changes in reproductive, neurological, metabolic, and immune-related processes (Richter et al., 2007).

Because of these findings, BPA exposure has been an area of particular interest in relation to sensitive life stages, including pregnancy and early development. Regulatory responses have included restrictions or bans on BPA use in certain products, such as baby bottles and some cosmetic applications, in parts of the European Union (Larsson et al., 2014).

It is also important to note that some “BPA-free” products use alternative bisphenols, such as bisphenol S (BPS), which are themselves being studied for similar endocrine-related activity. Research in this area is ongoing.

Triclosan

Triclosan is used as an antimicrobial agent in personal care products such as deodorants, toothpastes, mouth washes and shower gels, and also in consumer products such as cleaning products, plastics and toys (Bedoux et al., 2012)

Dioxins

Dioxins are a group of environmental pollutants that have been studied for their potential effects on human and environmental health. They are not intentionally added to products but can occur as by-products of certain industrial and manufacturing processes.

In research settings, dioxins have been examined for their interactions with hormonal pathways and cellular processes. Trace exposure has been identified in a range of environmental contexts, including some manufacturing chains associated with personal care and household products. Regulatory standards exist to limit exposure, and research in this area continues to evolve.

COMMON SOURCES OF ENDOCRINE-DISRUPTING CHEMICALS (ADAPTED FROM MERCOLA)

Modern life brings exposure to a wide range of environmental substances, many of which are being studied for their potential interaction with hormonal signalling. Research in this area is evolving, and exposure levels, relevance, and individual sensitivity vary widely.

Rather than alarm, the aim is awareness — understanding where exposures may occur and considering practical ways to reduce unnecessary contact where appropriate.

Drinking water

Some water supplies have been found to contain trace levels of substances such as atrazine, arsenic, or perchlorate in certain regions. These compounds are studied for their potential endocrine-related effects in research settings.

Awareness point: Water quality varies by location. Some people choose to explore filtration options based on local water reports and personal preference.

Canned foods

Bisphenol A (BPA) has been used in the lining of some cans and food packaging. BPA has been widely studied for its interaction with hormone receptors.

Awareness point: Some individuals choose fresh foods or store foods in glass or stainless steel where practical.

Meat, poultry & dairy

Antibiotics and hormone use in animal agriculture are regulated differently across countries, and residues are monitored. These practices are commonly discussed in the context of environmental and dietary exposure research.

Awareness point: Some people choose free-range, organic, or minimally processed options based on personal values and preferences.

Fish & mercury exposure

Certain large predatory fish are known to accumulate higher mercury levels. Mercury exposure is an area of active research in reproductive and neurological health.

Awareness point: Smaller fish such as sardines, anchovies, and herring are often included in discussions about seafood variety and lower contaminant exposure.

Office & occupational materials

Substances used in inks, toners, and industrial materials are sometimes included in studies examining workplace exposure and health.

Awareness point: Occupational exposure varies widely and is regulated in many settings. Awareness and basic hygiene practices are often emphasised.

Cash register receipts

Thermal paper receipts may contain BPA or related compounds. Research has examined transfer during handling, particularly under certain conditions.

Awareness point: Some people choose digital receipts or minimise handling where possible, based on personal comfort and awareness.

Personal care products

Personal care products may contain a range of chemical ingredients, including compounds that are studied for endocrine-related effects, such as phthalates.

Awareness point: Ingredient awareness and personal product choice is an area many people explore, depending on individual sensitivity, values, and preferences.

The bigger picture

Environmental exposures are just one part of a much broader health landscape. Understanding potential sources allows individuals to make informed, proportionate choices — without fear or perfectionism.

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