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The decline in sperm count threatens humans.The book says that chemical monsters

Grace Hauck

| USA Today


Well-known epidemiologists warn that humans are not only facing the coronavirus pandemic and climate crisis, but also threatened by the decline in sperm counts caused by chemical exposure.

“Chemicals in our environment and other lifestyle factors of modern people have damaged our reproductive health, so that in the future, most people may not be able to reproduce in the old fashioned way,” Shanna Swan said. An environmental and reproductive epidemiologist at the Icahn School of Medicine at Mount Sinai, New York, has more than 40 years of experience in this field.

According to a meta-analysis co-authored by Swan in 2017, between 1973 and 2011, male sperm counts in North America, Europe, Australia and New Zealand fell by more than 59%. At the current rate, half of the men’s sperm counts in these countries will decline. Swann told USA Today on Saturday that there will be no sperm by 2045, while many others have very few sperm.

Swann wrote in this week’s new book with science writer Stacey Colino: “Some things we have always thought of as fiction, such as “The Maid’s Tale” and “The Man’s Child” are being It quickly becomes a reality. How our modern world threatens sperm count, changes the reproductive development of men and women, and endangers the future of mankind.”

In his book, Swann believes that chemicals commonly used in the world today are interfering with hormones in the human body and causing deterioration in the reproductive health of men and women. These “endocrine-destroying chemicals” include chemicals that are water-soluble and flush out of the body, such as phthalates and bisphenol A (BPA), and “permanent chemicals” that do not degrade, such as perfluoroalkanes. Base substance (PFAS). .

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Swan said these chemicals enter the body through food and beverages, inhaled tiny airborne particles, and in products we absorb through our skin. They are found in plastic and vinyl, floor and wall coverings, medical tubing and medical equipment, children’s toys, nail polish, perfume, hair spray, soap, shampoo, etc.

She said, for example, phthalates are usually consumed through food.

“Adding them to plastic can make it soft and soft-think about shower curtains, rubber ducks, soft pipes. The processed food we eat enters the packaging through the soft pipes, and when the chemicals in these plastics come into contact with the food, , Phthalates will leach out of plastic and penetrate into food. When we eat food, they will enter our body,” she said.

Endocrine disrupting chemicals can interfere with hormones in several different ways. Swan said that phthalates may “deceive the body” into thinking that there is more testosterone than it actually is, causing the body to stop producing testosterone and increasing the chance of infertility or a reduced sperm count.

Dr. Pat Hunt, a geneticist at the Washington State University School of Molecular Biological Sciences, has been studying the effects of chemical exposure on male and female fertility, because a laboratory accident in 1998 made her aware of the harmful effects of household products.

Hunter said: “Over the years, as the evidence has become more and more convincing, I have been observing that the views of my scientific colleagues are changing.” “There is no doubt that the sperm count has declined. Due to exposure to these chemicals. The hypothesis that the number of spermatozoa has decreased has also become more and more trusted.”

However, some trade groups have questioned the link between endocrine-damaging chemicals and adverse health consequences, and some scientists have previously criticized studies for lack of evidence to show that there is a direct causal relationship between the two.

For example, Vinyl Authentic, an organization dedicated to raising public awareness of ethylene, wrote on its website: “Some competitive advantage and agenda-driven activists have launched dishonest campaigns to mislead consumers and deprive them of manufacturing products. Right. My own decision on vinyl.”

Some scientists question whether the sperm count is declining. Allan Pacey, professor of andrology at the University of Sheffield in the United Kingdom, said that although he believes that prenatal exposure to endocrine-damaging chemicals may affect the development of male fetuses, he still “expresses doubts about the data, which shows that Sperm counts have declined” and are therefore worldwide. “

Percy said: “I think science and medicine have accepted this hypothesis uncritically.” “Extraordinary claims usually require extraordinary evidence. However, in this case, it is clearly not necessary.”

Pacey performed a retrospective analysis of semen analysis data obtained in the past, and questioned the way scientists reached their conclusions. Pace said this analytical method is “weak” because the methods of andrology in the laboratory (such as training) have changed over time.

Pacey said that the 2017 study co-authored by Swan was “an improvement” because it used more control measures, but the study still did not provide “extraordinary evidence.” “I can’t prove it, but they can’t prove it either.”

Linda Birnbaum, former director of the National Institute of Environmental Health Sciences and the American Toxicology Program, said that the 2017 study was “impressive” and pointed out that Swann’s work also borrowed from animals, Study of boys and young people.

Birnbaum said: “Different researchers in different places have carried out repeated studies to support the decline in sperm count.” “This may be a complicating factor in this situation. I don’t think there is a single thing. But I It is true that chemicals that destroy endocrine secretions are part of the puzzle.”

People have no choice to reduce sperm count

Swan wrote that from 1960 to 2015, the global fertility rate fell by 50%. She acknowledged that many socio-economic factors are contributing to this decline, such as people choosing to have children in later years and smaller families.

Swan wrote, but surprisingly, fertility rates are falling at all ages. Not only is the number of sperm in men gradually decreasing, but the rate of abnormalities in the genitalia of boys is also higher. Among women of all ages, the risk of miscarriage has been rising.

Swan said: “Part of this picture has elements of selection, and some of them don’t.” People did not choose to reduce their sperm count.

Swan said that lifestyle factors-including diet, physical exercise, smoking and alcohol or drug use-change hormone levels and play a role in the decline. But Swan said she is most worried about chemical exposure, especially for pregnant women and children.

Swan said: “Other lifestyle factors work in a short-lived way.” “The reason why I focus on these early exposures to endocrine disruptors is that this will never change and will be passed on to future generations. Stories are more important, although they are much smaller and easier to control.”

Chemicals that destroy endocrine will not only affect reproductive health. Swan wrote that they are also related to “many adverse health effects in almost all biological systems,” including the immune, neurological, metabolic, and cardiovascular systems.

Hunter said: “We can see small changes in the development process, for adults, it can increase the incidence of cancer.” “We are letting our children have metabolic problems in adulthood, and I found this to be very disturbing. Incredibly thought-provoking and worrying.”

And we are not only hurting ourselves. We are also hurting animals.

Swan wrote: “These ubiquitous environmental chemicals have brought losses to the animal kingdom in many different ways.” “As a species, we cannot reproduce and reproduce ourselves, and hinder the ability of other species to reproduce.”

Disassembly, replacement and adjustment

Swan proposes an action plan in her book to help individuals change their daily habits and reduce exposure. Swann suggested using three new alternatives to the traditional “three rupees” to promote the reduction of exposure to plastics and other environmental chemicals: “remove, replace and manage” endocrine-damaging chemicals.

Swan said: “The chemicals themselves must be modified-to replace chemicals that can’t interfere with the human hormonal system. This is absolutely vital.” “They don’t have to be harmful at very low doses. They don’t have to be durable in the environment. exist.”

Hunter said her research on the effects of damaging endocrine chemicals has made her thinking about life “completely different.”

Hunter said: “You can’t eliminate plastic from your life, but you can buy different products.” “The plastic in my kitchen is silicone, and I use a lot of glass. There is a rule in my house that no plastic should enter the dishwashing area. Do not enter the microwave oven. Besides, I can’t forget to read the label.”

Swan also called for greater social changes, including strengthening government supervision of chemicals.

Hunter said: “We need to reconsider the entire chemical safety approach.” “We now place the responsibility on federal regulatory agencies to prove that these chemicals are harmful. The responsibility should be to prove that they are safe before use, not They proved to be dangerous after use.”

Swan said that for decades, the United States has experienced public outcry against certain chemical substances (such as bisphenol A), only replacing the chemical substance with the same harmful chemical substance.

She said: “This is a regrettable alternative, or informally known as “worse”. You knocked down one undesirable chemical substance into another chemical substance with a new name but with the same effect. . We need to stop this behavior.”.

Swan said she is launching a campaign related to this book to educate the public and the medical community about the dangers of damaging endocrine chemicals. Swan said she hopes to reach people of color, especially because many people are heavily affected by chemicals.

Swan said: “For example, because of the reduced supply of unprocessed fresh foods and their proximity to poor air and water quality, colored communities are overexposed.” “These communities are more affected by these chemicals and suffer more. The impact is also greater. There is an equity issue here, and we hope to resolve this issue.”

“These things are not separate”

Swan said that the discussion surrounding the reproductive health crisis in 2021 can be compared to the discussion surrounding climate change 40 years ago. Swan said: “Initially it was a denial, and then people began to accept that it was a problem.”

Swan said that in 1992, when a paper in the British Medical Journal suggested that sperm counts had gradually declined over the past 50 years, the paper “wasn’t taken seriously. It was criticized and almost ignored.” But in 2017, when Swan’s co-authored meta-analysis reached the same conclusion, the paper became one of the most cited scientific papers in the world that year.

She said: “Where they denied the problem in 1992, they said yes, it was a problem.” “Now, we need to enter the next stage, at which we assume our responsibilities as a society and as the earth.”

Swan said that discussions about the reproductive health crisis should be included in discussions around climate change and COVID-19. For example, many chemicals that destroy endocrine are made from by-products of petroleum production. In addition, recent papers also show that chemical exposure can increase the risk of severe disease caused by COVID-19.

Swan said: “These things are not separate, I think they should be considered together.” “We must realize that we face a triple risk.”

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