Dumb & Dumber - Part 2 - Explanation why do people become more stupid than before

If you haven't read my precedent post i will resume it rapidly.

The researchers have remarked an ALARMING thing.

For About twenty - thirty years, scientists have noted with concern that intellectual abilities are decreasing on a global scale.
A decline in IQ has been observed in several Western countries.
In addition, there is an explosion of cases of autism and behavioral disorders.

What is the reason of this alarming state ?

They spotted main cause :

Toxic chemicals in our environment mainly Endocrine disruptors , these chemical molecules that disrupt the functioning of the thyroid and other essential hormones development of the fetus. notably the development of the brain

They are present in pesticides, cosmetics, couch foams or plastics, these particles have invaded our daily lives.
We bathe in a real chemical soup.

In the United States, each baby is born with more than a hundred toxic chemical molecules in the blood.

• How do these chemicals interfere with brain development in fetuses and babies?

• Why is thyroid dysfunction involved in the erosion of our brain capacity ?

• Is it still possible to escape the effects of a toxic environment ?

• How to limit their effects?

• What solutions can be put in place to preserve the brains of future generations?

I will try to answer the 2 first questions in this post and the others in a third part because there is so much to say about it.

First : Explanation how these Chemicals affect the brain and body.

What are these Chemicals and how they come into our bodies ?

Bisphenol A (BPA), phthalates, alkylphenols, Perfluorooctanoic acid & other fluorinated chemicals, brominated flame retardants (BFRs), perchlorates, pesticides, lead, mercury ... endocrine disruptors , and others contaminants hide in clothing, furniture, packaging, food containers, dust and even in your food & water ! In fact they are everywhere !

The problem with endocrine disruptors is that they look like our natural hormones, and the brain does not differentiate them. If fetus or baby are exposed to these chemicals their brain & body develop with anomaly.

Endocrine disruptors may be associated with the development of learning disabilities, severe attention deficit disorder, cognitive and brain development problems; deformations of the body (including limbs); breast cancer, prostate cancer, thyroid and other cancers; sexual development problems such as feminizing of males or masculinizing effects on females

They are many type of endocrine-disrupting chemicals (EDCs) :

• The Xenoestrogens are a type of xenohormone that imitates estrogens (female hormones). Some others take place of androgens (male hormones) and of thyroid hormones

Synthetic xenoestrogens include widely used industrial compounds, such as PCBs, BPA and phthalates, which have estrogenic effects on a living organism numerous studies have found that laboratory animals exposed to low levels of it have elevated rates of diabetes, mammary and prostate cancers, decreased sperm count, reproductive problems, early puberty, obesity, and neurological problems

Bisphenol A (BPA) is a known endocrine disruptor, and numerous studies have found that laboratory animals exposed to low levels of it have elevated rates of diabetes, mammary and prostate cancers, decreased sperm count, reproductive problems, early puberty, obesity, and neurological problems. Early developmental stages appear to be the period of greatest sensitivity to its effects, and some studies have linked prenatal exposure to later physical and neurological difficulties

Polychlorinated biphenyls (PCBs) are a class of chlorinated compounds used as industrial coolants and lubricants.
The effects of acute exposure to PCBs were well known within the companies who used Monsanto's PCB formulation who saw the effects on their workers who came into contact with it regularly.
Exposure increases the risk of skin cancer, liver cancer and brain cancer.
Monsanto tried for years to downplay the health problems related to PCB exposure in order to continue sales.

Polybrominated diphenyl ethers (PBDEs) are a class of compounds found in flame retardants used in plastic cases of televisions and computers, electronics, carpets, lighting, bedding, clothing, car components, foam cushions and other textiles. Potential health concern: PBDE's are structurally very similar to Polychlorinated biphenyls (PCBs), and have similar neurotoxic effects

Comparison of BDE-47 (a PBDEs) and PCB-77 with Triiodothyronine (a thyroid hormones)

For those who don't have base in chemistry atoms of Chlorine, Bromine and Iodine are all in the same subclass called halogens so they react practically the same way its why the brain confound them with natural hormones plus the structure of molecules who are very close

Phthalates are found in some soft toys, flooring, medical equipment, cosmetics and air fresheners. They are of potential health concern because they are known to disrupt the endocrine system of animals, and some research has implicated them in the rise of birth defects of the male reproductive system

Alkylphenols are xenoestrogens. The European Union has implemented sales and use restrictions on certain applications in which nonylphenols are used because of their alleged "toxicity, persistence, and the liability to bioaccumulate" but the United States EPA has taken a slower approach to make sure that action is based on "sound science".
The long-chain alkylphenols are used extensively as precursors to the detergents, as additives for fuels and lubricants, polymers, and as components in phenolic resins. These compounds are also used in making fragrances, thermoplastic elastomers, antioxidants, oil field chemicals and fire retardant materials & also found in tires, adhesives, coatings, carbonless copy paper and high performance rubber products. They have been used in industry for over 40 years.

Certain alkylphenols are degradation products from nonionic detergents. Nonylphenol is considered to be a low-level endocrine disruptor owing to its tendency to mimic estrogen.

A comparison of the structure of estradiol a natural estrogen (left) and Nonylphenol(right)

The socio-economic burden of endocrine disrupting chemicals (EDC)-associated health effects for the European Union was estimated based on currently available literature and considering the uncertainties with respect to causality with EDCs and corresponding health-related costs to be in the range of €46 billion to €288 billion per year

One fact who is funny ( if we can sa funny in this case).
In the 1940s, they made sweaters and children’s cowboy chaps out of rayon fabric that would ignite easily and flash burn, and there was a scandal over the tragic deaths that resulted. So in 1953, they passed the Flammable Fabrics Act which required children’s pajamas and a number of other items like mattresses to be made from flame-resistant fabric. (There were state-specific laws as well.) Many people believe that the tobacco industry was behind all this because they wanted clothing and furniture manufacturers to be blamed for fires–rather than cigarettes.

For years flame-resistant chemicals were added to children’s pajamas, carseats, and other items. In 1977, when researchers discovered that two commonly used fire retardant chemicals (brominated and chlorinated tris) were very dangerous and mutated your DNA, those particular chemicals were banned. But in later years, folks started to figure out that even the “safer” fire retardant chemicals were potentially dangerous to kids: the chemicals were linked to increased hyperactivity and lowered IQ.

Despite the risks of flame retardants, the laws requiring flame retardant fabrics remained on the books.More than three decades after manufacturers stopped making children's pajamas with a flame retardant suspected of causing cancer, new research suggests the same chemical has become the most widely used fire-resistant compound in upholstered furniture sold throughout the United States.
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Now why thyroid is linked to low IQ and abnormal brain development ?

The link we have with the EDCs goes back far into the past.
A disease affected some people, this disease was cretinism. (from which the French word "cretin" come from to say of a person that he / she is stupid.
This disease disappeared in the early 20th century. The discovery of the relationships of sporadic cretinism with congenital hypothyroidism, and of endemic cretinism with hypothyroidism due to iodine deficiency. Both have been largely eliminated in the developed world.

Congenital hypothyroidism can be endemic, genetic, or sporadic. If untreated, it results in mild to severe impairment of both physical and mental growth and development.

Poor length growth is apparent as early as the first year of life. Adult stature without treatment ranges from 100 to 160 cm (3 ft 3 in to 5 ft 3 in), depending on severity, sex, and other genetic factors. In adults, Cretinism results in mental deterioration, swelling of the skin, loss of water and hair. Bone maturation and puberty are severely delayed. Ovulation is impeded, and infertility is common.

Neurological impairment may be mild, with reduced muscle tone and coordination, or so severe that the person cannot stand or walk. Cognitive impairment may also range from mild to so severe that the person is nonverbal and dependent on others for basic care. Thought and reflexes are slower.

Other signs may include thickened skin, enlarged tongue, or a protruding abdomen.

Cretinism (Styria), copper engraving, 1815

So the EDCs affect the thyroid system of fetus & baby and develop "a form of cretinism".

Its all for today I'll continue this series of post if you are interested, don't hesitate to upvote and comment. Thanks

Source : Many scientific article and Wikipedia if someone is interested in this subject i can send him the link to more specific papers