Endocrine disruptors: Why protect yourself from them?
Who hasn't heard of endocrine disruptors , environmental pollution, bisphenol?... But what are these substances called endocrine disruptors? Are they dangerous? Where are they found? Should we protect ourselves from them?
What is the definition of endocrine disruptors?
There is an official definition issued by the WHO in 2012; this definition is the one used in France and the European Union:
“An endocrine disruptor is a substance or mixture of substances that alters the functions of the endocrine system and thereby induces adverse effects in an intact organism, its offspring, or within (sub)populations.”
Endocrine disruptors are numerous (they are notably listed on a European list ). Endocrine disruptors constitute a real environmental pollution problem: they are present everywhere: air, water, soil, food, etc.
Some are considered proven endocrine disruptors, others are suspected of being so.
What do endocrine disruptors do to the body and health?
Endocrine disruptors (EDs) are substances that alter the hormonal function of organisms. In doing so, they alter their physiology and therefore disrupt the functioning of various systems such as:
- communication between organs, tissues or cells
- Developmental processes: growth, fetal development
- metabolism
- nutrition
- functioning of the nervous system
- immunity
- reproduction
How do endocrine disruptors work?
Endocrine disruptors interfere with the functioning of the hormonal system; they can act in three different ways:
- by disrupting the production of a hormone, its regulation, or its receptor. This alters the endocrine signal.
- by mimicking the message of a hormone (e.g., estrogen-mimics*)
- by preventing the hormone receptor interaction
*estrogenic: that which reproduces, in whole or in part, the action of estrogens
How are we exposed to endocrine disruptors?
A distinction must be made between cases of exposure in the workplace, due to the profession, and routine exposure for the general population.
Professionals in certain sectors are likely to be exposed to endocrine disruptors due to their work (agriculture, pharmaceutical industry, chemical industry, etc.). These professionals may be exposed to a number of substances such as plant protection products, pesticides, plastics, etc. In these specific cases, it is essential to adhere to personal protective measures.
Regarding the general population, among the sources of exposure to endocrine disruptors we can find:
- the ingestion of endocrine disruptors , in water or food due to substances that have migrated from packaging or residues present due to plant contamination (via soil)
- skin contact, particularly through contact with household products, cosmetics, and personal hygiene products
- inhalation
What are these molecules, and where are they found?
Endocrine disruptors are numerous and ubiquitous. However, a number of substances have come to light recently. Among these are:
-
Bisphenol A (BPA)
- Used in the manufacture of plastics and resins, it is found in packaging and everyday products. It is primarily ingested and has been implicated for its carcinogenic and estrogenic effects in humans. ANSES (the French Agency for Food, Environmental and Occupational Health & Safety) has identified the products and sectors using bisphenol A (BPA), so BPA is likely to be found in a wide variety of products, both food and non-food (sporting goods, industrial fluids, plastic packaging, receipts, etc.). Since January 1, 2015 (Law No. 2012-1442 of December 24, 2012), BPA has been banned in containers intended for direct food use.
-
Some phthalates
- They are present in some lubricants, detergents, solvents, and also in some pharmaceutical and cosmetic products. They have been banned in France since 2011. They are estrogenic and can cause developmental abnormalities and metabolic disorders. Absorption occurs through ingestion via the migration of these products under the influence of heat (in packaging).
-
Some parabens
- They are widely used in cosmetics where they act as preservatives, but they can also be found in some pharmaceutical products or in food as additives. They are particularly problematic for pregnant women because they can lead to fetal developmental abnormalities. They are also carcinogenic.
-
Alkylphenols
- They are found in everyday products and cosmetics, including detergents, paints, pesticides, spermicides, PVC pipes, hair dyes, and shaving creams. The EU prohibits their use in everyday products at concentrations above 0.1%. They have estrogenic activity and can lead to developmental abnormalities.
-
Butylated hydroxyanisole (BHA)
- Like BHT, it is used as an antioxidant preservative in some foods (E320) and cosmetic products. It helps prevent lipid oxidation, which is why it is found in creams, balms, lipsticks, and even some potato chips. It has estrogenic, neurotoxic, and carcinogenic properties. It is banned in some countries, but not yet in France.
- Butylated hydroxytoluene (BHT)
- It is used as a replacement for BHA and is abundant in cosmetic products. It is also found in food preparations (E321) such as cakes, chewing gum, breakfast cereals, etc. It is suspected of being estrogenic and carcinogenic.
-
Brominated flame retardants / polybrominated compounds (PBDEs)
- They are used as flame retardants in everyday objects: mattresses, foams, upholstery, vehicles, electronics, furniture, etc. They are very persistent in the environment and have effects that mimic thyroid hormones.
-
Lead
- It can be found almost everywhere, in (old) pipes, (old) paints, car batteries, pigments, etc. It is considered an endocrine disruptor and has neurotoxic effects.
-
Perfluorinated compounds (PFCs)
- They are found in some cosmetic creams, stain-resistant treatments for textiles, packaging (food and non-food), and sports equipment. They are particularly resistant and persist in the environment for a long time. They are carcinogenic and can cause metabolic disorders.
- Diethylstilbestrol (Distilbene)
- A former health scandal, it has estrogenic properties and is responsible for birth defects. It was a prescribed drug in France until 1977, when it was banned.
The specific characteristics of exposure to endocrine disruptors
For some compounds, it is clearly established that there are proven toxicities at high doses. For others, it is more complicated. There may be more subtle effects at lower doses, but also transgenerational effects**.
**Transgenerational: whose effect spans generations
Several distinctive features can be identified:
- Exposure doses / low exposure : some substances do not have a threshold effect and even a low dose can have effects.
- Non-monotonic dose-response relationships: We generally expect the effect to increase with the dose. The famous " the dose makes the poison " (monotonic dose-response curve)... This proverb may be true, but not in the way we usually understand it. Low doses of certain substances can have more effects than high doses; the toxicity curve is inverted (there are also toxicity curves called U-shaped or inverted U-shaped)...
- The issue of the window of exposure : There are critical periods when exposure to endocrine disruptors is likely to have a greater impact. This is the case during embryonic and fetal development, as well as early childhood.
- Cocktail effects : Combining exposure to several endocrine disruptors is likely to lead to interactions and effects at unexpected doses.
What about the regulations?
The use of chemical substances is regulated at the European level (REACH regulation), but there are also other specific regulations depending on the use.
Health authorities monitor substances suspected of being endocrine disruptors , and studies are conducted to determine their effects and exposure levels. In France, ANSES is involved in risk assessment. Following this risk assessment, lists of endocrine disruptors are established, and regulations are subsequently updated.
Can we protect ourselves from endocrine disruptors?
To protect oneself from endocrine disruptors , there aren't many strategies: the best is to avoid exposure...
Therefore, it is advisable to avoid products that contain them if possible:
- polycarbonate (PC-7) containers
- Do not use plastic containers in the microwave.
- pay attention to the type of food packaging
- Organic products are likely to contain fewer pesticides (suspected of being endocrine disruptors ).
- avoid cosmetics containing endocrine disruptors
- Ventilate homes to remove endocrine disruptors that can be released from paints
- Limit the use of pesticides/insecticides
Sources
Ministry of Solidarity and Health
Evaluation of endocrine disruptors by ANSES
National Strategy on Endocrine Disruptors
EFSA: Update on the non-monotonic dose-response relationship
WHO: Historic report on the human effects of exposure to endocrine disruptors