Why are endocrine disruptors so dangerous? How do estrogenics mimic estrogen?
An estrogenic is a chemical that mimics estrogen, which is a hormone that your body naturally produces. Estrogenics, which are just one category of endocrine disruptors, come from a variety of sources and can affect your health in significant ways.
Let’s look at how estrogenics work within our bodies and the characteristics that make them especially damaging.
Estrogenics Mimic Your Body’s Hormones
Jay explains that hormones are molecules that act as messengers, communicating between tissues and organs and regulating bodily functions like growth, appetite, and metabolism. Your body secretes hormones into your bloodstream, where they travel until they get picked up by matching receptors in cells located in various parts of your body. When the hormone latches onto a receptor, it triggers bodily processes crucial to your overall health and functioning.
Estrogen is a steroid hormone, which is a type of hormone derived from cholesterol. But, why are endocrine disruptors so dangerous? Estrogenics are harmful because they activate your body’s estrogen hormone response and disrupt your natural hormonal balance. Estrogenics are particularly dangerous because estrogen receptors are found all throughout your body—your brain, reproductive organs, muscles, and so on—which means estrogenics can affect nearly every part of your body. Consequently, they can lead to a wide range of health issues, including obesity, depression, hormone imbalance, immune system dysfunction, cancer, and infertility (we’ll discuss each of these later in the guide).
Estrogenics Have Prolonged Effects
According to Jay, estrogenics also pose a concern because they have a sustained effect on your health. Unlike your nervous system—which transmits quick but short-lived responses via neurons in your brain—once hormones attach to receptors in your body, they activate responses that can potentially last from several hours to days.
(Shortform note: Other experts note that the length of activation differs depending on the type of hormone. There are three main types of hormones: Peptides (such as insulin) have fast-acting and short-lived responses. In contrast, steroids (like estrogen) have slow-acting but long-lived responses. Amines typically have response times that fall between those of peptides and steroids, with some functioning quickly and others having lengthy responses.)
Not only do estrogenics have sustained effects, but they can also impact the health of your descendants. Jay writes that the effects of estrogenics on your body can be hereditary because your environment—including chemicals you’re exposed to—can alter your genes in ways that can be passed down to later generations. Specifically, chemicals can add molecules to your DNA sequences that change the way your genes behave, even if the exact DNA code hasn’t been modified. This is called epigenetics. Because epigenetic changes can be inherited, the effects of estrogenics can span generations.
How Your Environment Affects Your Health Although Jay claims that epigenetic changes can be inherited, other experts argue that there’s no conclusive evidence for this and claim that evolutionary mechanisms and biochemical processes during reproduction make it unlikely for epigenetic information to survive multiple generations. However, some argue that a pregnant woman’s environment, behavior, and diet can affect a baby’s epigenetics. According to experts, there are three ways epigenetic changes occur: 1. DNA methylation: This is a process where a chemical group attaches itself to your DNA at specific locations, inhibiting proteins from accessing and reading the gene. DNA methylation puts your genes in the “off” state, although a process called demethylation can switch it “on” again. 2. Histone modification: Your DNA is wound around proteins called histones, which can be packed tightly or loosely. The level of tightness affects a protein’s ability to read the gene—tight packing turns the gene “off,” while loose packing turns it “on.” 3. Non-coding RNA: Your body makes coding and non-coding RNA. Coding RNA is used to build proteins. Non-coding RNA can attach to coding-RNA and break it down so that it can’t be used to make proteins. |
Estrogenics Are Pervasive
Jay writes that another reason estrogenics are so dangerous is that they’re impossible to avoid. These artificial estrogens infiltrate the environment through land, air, and water, contaminating our food and water supply along with the everyday objects we use.
For instance, estrogenics in herbicides wash into lakes, rivers, and oceans in great quantities. Zooplankton and other organisms that live at the bottom of the food chain ingest these estrogenics. These chemicals accumulate as they move up the food chain, increasing the estrogenic load on creatures higher in the chain (such as humans). Because many types of estrogenics are so widely used, we’re all regularly exposed to a mixture of estrogenics, which magnifies their impact on our health.
Biomagnification: How Estrogenics Contaminate the Environment Chemicals increasing in concentration as they move up the food chain is a process known as biomagnification. Researchers have identified two key characteristics that determine whether and how well a chemical can biomagnify and accumulate up the food chain: 1. Ability to dissolve in water. Chemicals that don’t dissolve well in water accumulate in animal fats, leading to higher concentrations in top predators. 2. Ability to be metabolized by animals. Some chemicals are poorly metabolized, meaning they aren’t easily broken down and tend to remain in the animal’s tissues. As a result, these chemicals get passed up the food chain when the animal is eaten by another. Scientists add that certain ecosystems—such as oceanic environments with birds and mammals—are more susceptible to higher biomagnification than others. They argue that this is because these ecosystems have longer food chains with many levels of predators. Additionally, warm-blooded animals consume more food than cold-blooded animals, which means they consume and accumulate more of these chemicals. |
The US Regulates Estrogenics Poorly
Jay outlines another problem with estrogenics: They’re poorly managed. The United States trails behind Europe and other nations in regulating the use and disposal of estrogenics. The US doesn’t impose legal bans, restrictions, or limitations on numerous harmful estrogenic substances ranging from those found in foods to personal care products, and it allows far higher pesticide levels in drinking water—it permits three times the amount that Europe permits of the pesticide atrazine in water supplies.
Why US Regulation Lags Behind Experts suggest several reasons many toxic substances banned or restricted in Europe and other countries continue to circulate freely in the US: 1. Influence of the chemical industry: Key legislation, like the Toxic Substances Control Act, has been drafted with significant input from the chemical industry. As a result, these laws are more concerned with minimizing inconvenience to businesses than with protecting public health. 2. Legally, chemicals are considered harmless unless proven otherwise: In America, it falls to the government to prove that a chemical is harmful before banning or restricting it. Europe works the other way round—if there’s evidence that a substance could be risky, the burden is on the manufacturer to prove its safety. 3. Lack of action after regulatory failures: When efforts to ban harmful substances have failed in the past, regulatory bodies have often not attempted to try again, resulting in harmful substances remaining readily available. 4. Inadequate resources: The process of regulating chemicals takes years, and the Environmental Protection Agency (EPA) has struggled to do its job due to a lack of funding and staff. 5. The “Generally Recognized As Safe” (GRAS) loophole: The GRAS loophole was made in 1958 and allowed companies to use certain ingredients without thorough safety review. Originally, companies would ask the FDA to confirm these ingredients were safe, but since 1997, they can just say a new chemical is safe and add it to foods without telling the FDA. Because of this, almost all new chemicals added to US food since 2000 entered under the GRAS rule. |
Scientific Research Suffers From Biases
If estrogenics are so problematic, why don’t we know more about them and why don’t governments impose greater restrictions on them? Jay proposes three explanations: the impact of funding on published research, bias within the scientific community, and the lack of reliable scientific studies.
First, Jay explains that scientific investigations can be distorted because research institutions rely on external funding to conduct studies, and that funding can come with strings attached. American labs typically receive funding from either the government or from large corporations. To secure this funding, labs must research topics that appeal to government or corporate interests.
Because of this, scientific research data can often be biased. For example, Jay notes that many products containing estrogenic chemicals are major revenue earners for corporations. When one of these corporations backs a study, the findings tend to tilt in the product’s favor.
Second, Jay points out that there are shortcomings in how scientific research is validated. In the peer review process, for instance, researchers can suggest who should review their work (such as their colleagues), which can potentially lead to biased evaluations.
Third, Jay adds that many scientific studies are unreliable: They’re prone to inaccuracies such as miscalculations, misinterpreted results, or simple human error, so that when replicated, they fail to yield similar results. Because of this, there are many unreliable studies that provide contradictory information about estrogenics. This confusion could explain why the risks of estrogenics aren’t well known and why governments may hesitate to enact regulations.