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Human sperm. Credit: Wikipedia

Back in 2017 the world was shocked by a major study that focused on dropping sperm counts in men living in Western countries - a drop of over 50% in 4 decades, or about 1% per year. Along with an increase in infertility. If the drop in sperm counts continues at its current pace, it ultimately means that humans soon will not be able to reproduce. Worse case scenario: extinction of humans.

Dr. Shanna Swan, who an author of the study, has a just published an excellent eye-opening book about this topic. The cause for these sperm count drops and increasing infertility are the hormone (endocrine) disrupting chemicals in everyday products all around us. In plastics, in many pesticides, in personal care products, in our foods (from the packaging)... Yes, all around us. It turns out these chemicals have all sorts of harmful health effects, not just lowering of sperm counts and increasing infertility. [see below]

Good news: we can't escape all the harmful chemicals around us, but we can really decrease our exposures and so decrease the levels of these chemicals in our bodies. And it's better for our health! For tips on ways to reduce your exposures and the levels of harmful chemicals in your body - see Avoiding Harmful Chemicals.

The highly recommended book is written by Shanna Swan, PhD and Stacey Colino: Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race. Scribner, 2020. With many pages of references at the end.

An interesting short interview with Dr. Shanna Swan. From The Intercept: TOXIC CHEMICALS THREATEN HUMANITY’S ABILITY TO REPRODUCE

..a book that ties industrial chemicals in everyday products to a wide range of changes taking place in recent years, including increasing numbers of babies born with smaller penises; higher rates of erectile dysfunction; declining fertility; eroding sex differences in some animal species; and potentially even behaviors that are thought of as gender-typical.

Excerpts by Shanna Swan and Stacey Colino's piece from Scientific American: Reproductive Problems in Both Men and Women Are Rising at an Alarming Rate

When you see or hear a reference to “the 1 percent,” most people think of socioeconomic status—the people with the top 1 percent of wealth or income in the United States, which is how the term is commonly used in our culture.

Not us, though.  ...continue reading "A New Book Discusses Falling Sperm Counts and The Chemicals Around Us"

There is much concern nowadays about all the many chemicals we are exposed to in our lives. These include pesticides, heavy metals (e.g. lead, mercury), and chemicals that act as endocrine disruptors (hormone disrupting chemicals), such as BPA and phthalates. These chemicals are all around us and are linked to all sorts of health effects, including chronic diseases and reproductive effects - such as infertility, declining sperm counts, adverse effects on the developing baby, and endometriosis.

There is an excellent 7 part series of webinars that one can watch called Generation Chemical: How Environmental Exposures are Affecting Reproductive Health and Development. Big names in the field discuss the latest science on the impact of harmful chemicals and pollutants on female and male reproductive health, pregnancy, and development, starting from preconception and through  life.

Yes, it's in depth, but also eye-opening. For example, the evidence is now raising the questions: Are fertile people healthier? Does poor sperm quality mean poorer health? Or earlier death? Research suggests that sperm count and quality are "canaries in the coal mine" for male health - evidence of harm to men from environmental and lifestyle influences.

Also, keep in mind that while you can't totally avoid harmful chemicals, you can really minimize your exposure and the levels measured in you. Avoiding Harmful Chemicals gives good ways to reduce exposures to harmful chemicals. This is especially important for both males and females if thinking about conception or pregnant.

SEVEN PART WEBINAR SERIES: 1) Introduction. Oct. 29, 2020. Discussed declining sperm counts that have been occurring worldwide over the last few decades - 52.4% decline in 38 years among men from Western countries, and the decline is still continuing. Effects of endocrine disrupting chemicals (EDCs) on men's and women's fertility, conception delay, pregnancy loss, some diseases, and endometriosis. ...continue reading "Top Scientists Explain How Harmful Chemicals Are Affecting Reproductive Health and Development"

Two years ago scientists reported an alarming and steep decline in sperm counts in men from Western industrialized countries over the last 40 years. Both sperm count and sperm concentration declined 50 to 60% in this period in men in North America, Europe, Australia, and New Zealand. Especially concerning was that there was no evidence of this year by year decline leveling off.

What does this mean? As these declines continue, more and more men will have sperm counts below the point at which they can reproduce. Instead they will be infertile or "sub-fertile" (fertilization is unlikely). According to the World Health Organization (WHO), a sperm count of below 15 million per ml makes a man subfertile. However, also of concern is the threshold level associated with a "decreased monthly probability of conception", which is 40 million/ml - which means conception will take significantly longer (due to impaired ability to fertilize an egg).

A recent Univ. of Geneva study looked at semen quality of 2523 young men (aged 18 to 22 years old) who were being drafted into the military in Switzerland. They found that average sperm quality and sperm concentration of the men, who were from all regions of Switzerland, was among the lowest in Europe (along with Germany, Denmark, and Norway).

In Europe, median sperm count ranges from 41 to 67 million per milliliter (ml), depending on the country. The researchers found that the group of Swiss men had a median sperm count of 48 million per ml. And 17 percent of the men had sperm counts below 15 million per ml (thus subfertile). By the way, countries with lower sperm counts and quality, have higher rates of testicular cancer - they go hand in hand.

Also, in a quarter of the Swiss men studied, less than 40 percent of sperm cells were motile (moved normally), and 43 percent of men had less than 4 percent normally formed sperm. Overall, only 38 percent of Swiss men had healthy sperm - that is, with concentration, motility, and morphology (shape, form) that met the WHO’s criteria for healthy sperm.

Why is this happening? The researchers found that of the men with very low sperm concentration, more of their mothers smoked during the pregnancy, which means there could be changes during embryonic development. Also, while this study did not discuss this, many other researchers say that sperm health is "the canary in the mine" for male health - evidence of harm to men from environmental and lifestyle influences. 

These Western developed countries are awash in chemicals and plastics, also with endocrine disruptors (hormone disruptors) in our foods, our personal care products, in products all around us - and so studies find these chemicals in all of us (in varying degrees). Same with flame retardants, pesticides, "scented" products. Exposure to all sorts of environmental pollutants - whether in air, water, soil, our food - such as high levels of aluminum. All of these can have an effect on sperm counts and reproductive health. You can't totally avoid these chemicals, but you can try to lower your amounts of exposure (some tips to lower exposures).

From Medical Xpress: Poor semen quality in Switzerland   ...continue reading "Male Fertility Is Plunging In Switzerland"

To the alarm of many, male fertility (sperm quality and sperm counts) has been rapidly declining over the past few decades. Researchers suspect that it's due to our exposure to chemicals in the environment, especially to endocrine disrupting chemicals - of which there are many, and to which we are exposed to daily. A recent study found that detrimental effects occur in the sperm of both humans and dogs when exposed to the common plastic softener DEHP and the persistent industrial chemical polychlorinated biphenyl 153 (PCB153). The researchers suggest this is because dogs live in households with humans and thus are exposed to the same environmental contaminants.

DEHP (diethylhexyl phthalate) is an endocrine disruptor (interferes with hormone systems) that is found in plastic materials in many household and personal items - for example, in carpets, vinyl flooring, some upholstery, rainwear, wires, some plastic toys, fragrances and air fresheners, some PVC pipes, some food packaging, medical tubing, plastic shower curtains. The problem is that it slowly leaches out of the products and into the air and household dust, it leaches out of packaging into foods (which we then ingest), and it can also be absorbed through direct skin contact. Bottom line: try to avoid DEHP by avoiding plastics known as polyvinyl chloride (PVC) or vinyl as much as possible. (One can't totally avoid them, but can reduce exposure to them.)

From Science Daily: Chemical pollutants in the home degrade fertility in both men and dogs, study finds

New research by scientists at the University of Nottingham suggests that environmental contaminants found in the home and diet have the same adverse effects on male fertility in both humans and in domestic dogs.  ...continue reading "Common Chemical Has Negative Effects On Sperm of Both Humans and Dogs"

New research is published every day, but only some studies are big research stories or game-changers. The following are what I consider some of the most memorable studies of 2018 – some in a good way, but some of the others have left me with a sense of horror. I think there will be follow-up research, so keep an eye out for more on these important topics.

Are we heading toward a time in the not so distant future when all men are infertile? (Due to exposure to all the endocrine disruptors around us.) Will All Men Eventually Be Infertile? This was posted September 5, 2018.

Researchers are now seriously investigating and finding evidence that microbes may be causing Alzheimer’s disease. This approach is rapidly finding support in the medical field, and may lead to possible ways to treat or prevent the disease. Possible Herpes Virus Link to Alzheimer’s Disease was posted July 13, 2018, and Herpes Viruses and Alzheimer's Disease on  June 22, 2018.

Type 2 Diabetes May Be Reversed With Weight Loss was posted August 10, 2018. This study and an earlier similar study from 2016 found that losing over 30 pounds over a short period can reverse type 2 diabetes - 46% in the 2018 study and 60% (in people who had it less than 10 years) in the earlier study.

More and more evidence is accumulating that certain diets are anti-inflammatory. Especially beneficial are diets rich in fruits, vegetables, seeds, nuts, legumes (beans), and whole grains - which also have a lot of fiber. This is exciting research because chronic low-grade inflammation is linked to a number of chronic diseases (heart disease, cancer, etc.). Fruits, Vegetables, and Whole Grains Lower Inflammation – posted August 1, 2018.

[Related to this last topic is one of the most eye-opening studies I have ever read on how what one eats has a quick effect on gut microbes and health of the gut (including inflammation of the colon): Changing Diet Has Big Effect On Colon Cancer Risk – posted April 28, 2015.]

Image result for human sperm, wikipedia The last post discussed the steep ongoing decline in sperm counts and sperm concentration in men from North America, Europe, Australia, and New Zealand. It mentioned a number of environmental causes that could be contributing to this, including the huge increase of chemicals, especially endocrine disruptors (chemicals that disrupt our hormones) over the past few decades.

But another study was also just published that showed (in mice) that effects of chronic exposure to endocrine disrupting chemicals are amplified over 3 generations - and each generation has even lower sperm counts, sperm concentration, and reproductive abnormalities. So each generation gets progressively worse with continued exposure.

As the researchers state: "Our findings suggest that neonatal estrogenic exposure can affect both the reproductive tract and sperm production in exposed males, and exposure effects are exacerbated by exposure spanning multiple generations. Because estrogenic chemicals have become both increasingly common and ubiquitous environmental contaminants in developed countries, the implications for humans are serious. Indeed, it is possible effects are already apparent, with population-based studies from the U.S., Europe, Japan, and China reporting reductions in sperm counts/quality and male fertility within a span of several decades." Yikes...

The World Health Organization (WHO) considers an impairment in ability to fertilize an egg at 40 million sperm per milliliter or below, and the level where WHO considers fertilization unlikely is 15 million sperm per milliliter. This is why the sperm count study discussed in the last post is so frightening: North American, Canadian, Australian, and New Zealand men  whose partners are not yet pregnant nor do they have children (i.e., they are not confirmed fertile men) have experienced a drop in average sperm count of about 50 percent over four decades, to 47 million sperm per milliliter. Niels Skakkebæk, a Danish pediatrician and researcher working on this topic said: "Here in Denmark, there is an epidemic of infertility."and "Most worryingly [in Denmark] is that semen quality is in general so poor that an average young Danish man has much fewer sperm than men had a couple of generations ago, and more than 90 percent of their sperm are abnormal." Uh-oh...What will it take for governments to address this serious issue?

In the meantime, see the last post for some tips on how to reduce your own exposure to endocrine disrupting chemicals. Just note that you can reduce exposure, but you can't totally eliminate exposure. Excerpts from Environmental Health News:

Science: Are we in a male fertility death spiral?

Margaret Atwood's 1985 book, The Handmaid's Tale, played out in a world with declining human births because pollution and sexually transmitted disease were causing sterility. Does fiction anticipate reality? Two new research papers add scientific weight to the possibility that pollution, especially endocrine disrupting chemicals (EDCs), are undermining male fertility.

The first, published Tuesday, is the strongest confirmation yet obtained that human sperm concentration and count are in a long-term decline: more than 50 percent from 1973 to 2013, with no sign that the decline is slowing. "The study is a wakeup that we are in a death spiral of infertility in men," said Frederick vom Saal, Curators’ Distinguished Professor Emeritus of Biological Sciences at the University of Missouri and an expert on endocrine disruption who was not part of either study.

The second study, published last week by different authors, offers a possible explanation. It found that early life exposure of male mouse pups to a model environmental estrogen, ethinyl estradiol, causes mistakes in development in the reproductive tract that will lead to lower sperm counts. According to vom Saal, the second study "provides a mechanistic explanation for a progressive decrease in sperm count over generations." What makes this study unique is that it examined what happened when three successive generations of males were exposed—instead of just looking only at the first. Hunt, in an email, said "we asked a simple question with real-world relevance that had simply never been addressed."

In the real world, since World War II, successive generations of people have been exposed to a growing number and quantity of environmental estrogens—chemicals that behave like the human hormone estrogen. Thousands of papers published in the scientific literature (reviewed here) tie these to a wide array of adverse consequences, including infertility and sperm count decline. This phenomenon—exposure of multiple generations of mammals to endocrine disrupting compounds—had never been studied experimentally, even though that's how humans have experienced EDC exposures for at least the last 70 years. That's almost three generations of human males. Men moving into the age of fatherhood are ground zero for this serial exposure.

So Horan, Hunt and their colleagues at WSU set out to mimic, for the first time, this real-world reality. They discovered that the effects are amplified in successive generations. They observed adverse effects starting in the first generation of mouse lineages where each generation was exposed for a brief period shortly after birth. The impacts worsened in the second generation compared to the first, and by the third generation the scientists were finding animals that could not produce sperm at all. This latter condition was not seen in the first two generations exposed. Details of the experimental results actually suggested that multiple generations of exposure may have increased male sensitivity to the chemical[Original study.]

U.S. government agencies (such as FDA) say phthalates are OK, but evidence is mounting that they definitely are not OK. It's impossible to totally avoid phthalates, but one can lower exposure amounts by eating whole unprocessed foods, not microwaving or storing food in plastic containers (best is glass), and read ingredient lists on labels, including personal care products. From Medical Xpress:

Plastics chemical tied to changes in boys' reproductive development

When expectant mothers are exposed to plastics chemicals called phthalates during the first trimester, their male offspring may have a greater risk of infertility later in life, a new study suggests.Boys exposed to the chemical diethylhexyl phthalate (DEHP) may be born with a significantly shorter anogenital distance than those not exposed to these chemicals. Anogenital distance is the distance between the anus and the genitals. A shorter anogenital distance has been linked to infertility and low sperm count, the researchers explained.

"We saw these changes even though moms' exposure to DEHP has dropped 50 percent in the past 10 years," said lead researcher Shanna Swan, a professor of preventive medicine and obstetrics, gynecology and reproductive medicine at the Icahn School of Medicine at Mount Sinai in New York City. "Therefore, we have not found a safe level of phthalate exposure for pregnant women," she contended.

Swan said that this study cannot prove that these boys will have fertility problems as adults or that DEHP causes these problems. However, animal studies have implicated the chemical in male reproductive problems. Based on the data from this study, Swan believes there is a strong association between exposure to DEHP and fertility in human males.

DEHP is used to soften plastics. Most exposure results from eating foods that pick up the chemical during processing, Swan said. "Since food is the largest source of DEHP for consumers, it is difficult for pregnant women to minimize exposure," she said. "Eating unprocessed food will likely help. However, eliminating DEHP from food really has to be done by food producers."The chemical is also found in medical tubing and in a variety of products, including flooring, wallpaper, lacquers and personal care products, Swan said.

For the study, Swan's team collected data on almost 800 pregnant women and their infants.Specifically, the researchers found that exposure in the womb to three types of DEHP was associated with a significantly shorter anogenital distance in boys, but not in girls.

A group representing the chemical industry took issue with the study, however. In a statement, the American Chemistry Council (ACC) stressed that the study only examined one type of phthalate, not all versions of the chemical... The ACC added that DEHP "is known to break down into its metabolites within minutes after it enters the body. 

But another expert says phthalate exposure may not be benign. Dr. Kenneth Spaeth, director of the Occupational and Environmental Medicine Center at North Shore University Hospital in Manhasset, N.Y., said, "virtually everyone in the U.S. experiences continual exposure to phthalates."And, a number of studies have tied the chemicals with changes in developing fetuses. "Phthalates, in particular, have been shown in both human and animal studies to interfere with normal fetal development," he said.

This study supports what has been demonstrated before, that phthalate exposure in the first trimester is linked to male reproductive development, Spaeth said. "This study is an important step forward in establishing this effect because the study included a much larger number of individuals than prior studies and helps identify one particular agent, DEHP, as an important contributor to this effect," he said.Additionally, this study shows the importance of exposure in the first trimester as a critical window for the effect of phthalates on the male reproductive system.