Plastic Harms Men’s Fertility: How to Protect Your Health

Plastic harms men’s fertility and is invading their reproductive systems. Here we shed light on the health risks of plastics and what you can do to protect yourself, to help keep yourself and future generations healthier.

Plastic poisons people. While unborn babies, infants, children, and pregnant people are among those most vulnerable to the toxic impacts of plastic, evidence of plastic harming men’s health is also growing. Specifically, with plastic particles found throughout men’s reproductive systems, concerns are growing around the threats of plastic to men’s fertility, sexual function, and overall reproductive health.

It’s concerning to learn of plastic’s harmful impacts on our bodies. Yet, there are things you can do to better protect your health.

Microplastics Found in Men’s Reproductive Systems

It appears that the amount of microplastics accumulating in men’s testicles is among the highest found in any human body part: higher than what has been found in mothers’ placentas, and second only to the human brain, the organ which appears to be harboring the highest levels of plastic particles.

This year, scientists published the results of a small study assessing 23 human and 47 dog testicles for plastic particles. Unfortunately, the researchers found microplastic in all of testes analyzed. The most common type of microplastic found was polyethylene (PE), a plastic commonly used to make single-use bags and bottles. The next most common type was polyvinyl chloride (PVC), which is used for many purposes, from food packaging, to car interiors to building materials such as water pipes. The human testicles contained almost three times as many microplastics as those of the dogs, suggesting a higher level of exposure.

Human sperm samples are also testing positive for microplastics. In another small study published this year, scientists found plastic particles in all 40 of the sperm samples they collected from men undergoing routine sexual health assessments in China. They detected eight types of plastics in these samples, with polystyrene (PS)—from expanded polystyrene (EPS) foam items, like takeout clamshells, PE, and PVC being the most common. Other researchers have also found high levels of PS microplastics in sperm samples.

What’s more, scientists have also recently discovered microplastics in human penises for the first time. In a small study, four out of five men being treated for erectile dysfunction were found to have microplastics in their penis tissue. Of seven different plastics detected, the most common types of plastics included polyethylene terepthalate (PET) and polypropylene (PP).

Once they enter the human body through inhalation, ingestion, or contact with skin, plastic particles seem capable of traveling through our internal systems—much like the way plastic particles polluting the environment are known to travel through Earth’s atmosphere and air, oceans, freshwaters, and soils. Plastic particles have also been found in people’s bloodstreams, breast milk, feces, hearts, lungs, and veins, with more worrying research now on the way.

Plastic and Its Chemicals Harm Men’s Fertility

Plastic production and pollution is on the rise, and, unfortunately, so is male infertility. While the exact mechanisms of how microplastics and plastic chemicals harm reproductive health are still being fully understood, scientists have already learned a few key facts:

Microplastics decrease testes weight, and reduce and harm sperm

The presence of microplastics in men’s reproductive systems appears to decrease testes weight and sperm count. Scientists have found that the higher the levels of polyethylene and PVC plastic particles found in human and dog testicles, the lower the weight of the testicles. In dogs, the scientists linked the presence of PVC particles to lower sperm counts. Smaller testicles tend to produce less sperm, which can cause fertility issues. Experts estimate sperm levels globally could trend towards zero by 2045. This makes the issue of plastics, chemicals, and fertility a matter of human survival

Other studies have linked microplastic exposure, especially exposure to polystyrene, to infertility issues including increased sperm abnormalities and death, reduced sperm count and viability, and reproductive system damage in male mice and rats. Researchers have noticed that sperm found in samples with PVC move abnormally, and all sperm samples containing microplastic tend to have sperm with harmful mutations that impair their survival.

Plastic chemicals are linked to infertility and erectile dysfunction

PVC is considered one of the most toxic types of plastics because it contains dangerous ingredients plus harmful additive chemicals, including phthalates, which are known to interfere with normal hormone functions in the human body. Exposure to PVC plastic and the endocrine- (hormone-) disrupting chemicals it contains has been linked to serious health problems, including numerous reproductive issues in males, including undescended testes, premature puberty, and low sperm count.

There is ample and growing evidence that the hormone-disrupting chemicals in plastics‚ which are numerous and include bisphenols (like bisphenol A, or BPA), dioxins, flame retardants, PFAS “forever chemicals,” phthalates, toxic metals, and many others, have serious effects on the human body, and especially the reproductive system. In men, hormone-disrupting chemicals found in plastics have been linked to erectile dysfunction, reduced sperm counts and health, and many other reproductive abnormalities linked to infertility.

Additionally, experts say the presence of microplastics in the penis and body may potentially be linked to erectile dysfunction in men, and that more research is needed.

Environmental injustice and industrial air pollution linked to fertility issues

According to some estimates, about 70 percent of people employed by the plastic industry identify as men. Worldwide, about 20 million people work in the informal waste sector, picking through plastic pollution to make a meager living while facing the dangers of plastic pollution often without any form of health-protecting equipment. Many waste pickers are men. 

In the workplace, whether in a plastic factory or at a plastic dump site, workers face exposure to plastic particles and chemicals through inhalation, ingestion, and skin contact. Those working in close proximity to plastic often risk their lives, with accidents such as fires and explosions occurring frequently.

Similarly, people living in low-income, rural, and Black, Indigenous, and/or People of Color (BIPOC) communities are most likely to find themselves on the industrial fencelines of plastic and fossil fuel pollution. Such proximity to plastic pollution, transportation, and disposal exposes communities to an array of toxic air, water, soil, and bodily pollutants—including microplastics and the chemicals they contain. Exposure to plastic pollution has been linked to all manner of health serious issues, including autoimmune disorders, cancers, heart disease, infertility, reproductive issues, respiratory problems, and much more.

Take Action

While it is concerning to learn about the ways plastic is harming our health, the good news is steps can be taken to avoid plastic as much as possible. Learn more by using our guides and reading our blogs, which include actionable steps for eliminating plastic from your everyday life, from home cleaning supplies, to your wardrobe, and much more.

Besides taking individual actions to reduce the risks of plastic pollution exposure, we need wider systemic change to better protect our health. Plastic poisons people, and the only way we can halt the harm is to significantly reduce plastic production. With the UN Plastics Treaty set to be finalized by the end of this year, world leaders now have the opportunity to agree to cap plastic production. Join the call for an ambitious treaty during the final negotiating session in November 2024 that will allow us to end plastic pollution. If you’re in the U.S., sign the petition here. If you’re outside the U.S., sign the petition here.


And that’s what we see with sperm decline. We do see a dramatic decline. Dramatic decline. Cut in half—99 million per milliliter in 1973 and down to 47 million per milliliter in 2011. That’s 39 years. It’s a decline of 52% which is faster than 1% per year, and if you thought about anything else, like breast cancer or ADHD or anything else increasing or changing at that rate people would be up in arms. But for some reason, they’re not so alarmed about this decline.

Dr. Shanna Swan

Dr. Shanna Swan (@DrShannaSwan) is an epidemiologist and ​​Professor of Environmental Medicine and Public Health at the Icahn School of Medicine at Mount Sinai, where she has taught since April 2011. She has spent more than 25 years researching the effects of various chemicals on the environment and human health. 

Her research into the impacts of plastics, PFAS, and other chemicals of concern on declining sperm counts and neonatal development in human populations has earned her international recognition. In 2017, she co-authored a paper sounding the alarm on sperm levels trending towards zero by 2045. In 2021, she authored the book Count Down: How Our Modern World is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race.

For our inaugural episode of Plastic “Tox,” Dr. Swan sat down with Plastic Pollution Coalition CEO and Co-Founder Dianna Cohen to discuss the effects of phthalates on neonatal children through products their mothers used or ingested—from food packaged or heated in plastic to cosmetic products where phthalates are added to increase absorption of fragrances. As it stands, companies are allowed to include plasticizing chemicals in their products without informing consumers of their presence. There is no watchdog, outside of NGOs and activists akin to the FDA monitoring chemicals of concern.

Listen and learn more!


Hi, I’m Dianna Cohen, CEO and Co-Founder of Plastic Pollution Coalition. And today I’m talking with Dr. Shanna Swan, the author of Countdown. Shanna, welcome.

Thank you, Dianna. I’m happy to be here to talk to you about Countdown and the problems that I talked about in Countdown and other problems. I’m a Professor of Environmental Medicine and Public Health at the Icahn School of Medicine in Mount Sinai in New York. And I’ve been studying the effect of chemicals in plastic and other endocrine disruptors for over 20 years. And I’m happy to tell you about some of my findings.

Wonderful. Well, thank you for making the time to talk with us today. So let me just go right into some questions that I have for you. I’ve read your book, Countdown, and one of the most alarming facts, was the data showing average sperm levels trending towards zero by – was it 2040 or 2045? So I was wondering, in your opinion, are the chemicals and plastic contributing to a gradual chemical castration or infertility of humans as a whole? And if you could talk about that?

… Yes. 

To answer your question now, let me go into some detail. So first of all, let me say something about going to zero in 2045. You know, that’s kind of deceptive. You can draw the sperm decline line—which, by the way, is in Western countries in our published data, and probably the one you’ve seen—that line would, in theory, reach zero in 2045. 

However, it can’t ever reach zero. And that’s a mathematical conundrum if you will. It can go lower and lower. But since we’re looking at a mean of something that can’t be negative, you can’t have a negative sperm count. So the mean can’t ever be zero, because that would imply that a substantial portion of men had counts below zero, which is not possible. 

So what actually happens when things approach a lower limit biologically is that they can come closer and closer but never reach it. And that’s what we see with sperm decline. We do see a dramatic decline. Dramatic decline. Cut in half—99 million per milliliter in 1973, and down to 47 million per milliliter. In 2011, that’s 39 years. It’s a decline of 52%, which is faster than 1% per year. And if you thought about anything else, like breast cancer, or ADHD, or anything that was increasing or changing at that rate, people would be up in arms, but for some reason, they are not so alarmed about this decline. 

But I do believe and you asked about, could it be plastics? Yeah, so for me, I’m a scientist. So belief isn’t really part of my equation. I look for data. And that’s what I did when I saw this firm decline. So I started doing research around 2000, and looking at a number of chemicals in the environment that could be playing a role. But first I convinced myself that the environment was important. And I did that by looking at sperm counts in different environments where they were measured in the same way and the men were similar. And yet, we saw a huge difference. 

Here’s a number. Minnesota had twice as many moving sperm as Columbia, Missouri, which is rural, small town, Middle America, covered with pesticides. And there we showed that it was the pesticides that were significantly linked to sperm decline/sperm count, which is implicated. 

But then after that, I started thinking about something which toxicologists had talked about which was something called a phthalate syndrome. Now the phthalate syndrome, we can say what it is, but the first remarkable thing about it is that it exists at all. That there is a syndrome named after phthalates; plasticizers that make plastic soft and flexible and do other things as well, which I’m sure we’ll talk about. But the fact that there’s a syndrome, what does that mean? That means that something that’s so important that scientists have singled it out to name it as a condition, and it’s something that appears at birth in males, when the mother was exposed to phthalates. That’s why it’s called “the phthalate syndrome.”

So when I heard about this, I thought I was really alarmed. And I decided to ask, do we see that not only in the laboratory in animals? Do we see that in humans as well? And so I spent 20 years answering that question, and the answer is yes. 

So that’s why I not only believe that plastics are playing an intimate role in sperm decline and fertility decline in reproductive function decline, but I have the evidence that you can interfere with fertility and semen quality and so on, by messing with the hormones of an unborn fetus with phthalates, and now we know other chemicals as well.

And have you looked at bisphenols as well?

Yes, we have. And bisphenols are also bad news for reproduction. They’re not linked directly to sperm count, however, so since that’s where I focus a lot of my work. And we don’t have them linked to specific malformations of the male genital tract, which is the other area where I focus my work, while other people have worked and shown that bisphenols are also really harmful for reproductive function.

It’s pretty interesting to watch industry’s response to the evidence and the scientific research that came out around BPA, Bisphenol A, and how easily they—it’s almost like a PR move—made the shift to saying things were BPA free, and just switch to a different bisphenol that maybe was one molecule different. But from what I understand, many of those are equally bad, if not worse, to BPA. The BPA substitutes,

Right. And so what you’re describing a practice that we call “regrettable substitution,” or “Whack-a-Mole.” 

Roseanne Rodale called it “Whack-a-Mole.” 

But I call it “scamming.” You know how people are very alert to scamming these days? Scammers come in on your email and, and mess with your head and mess with maybe a lot worse than your head. And that’s just a kind of scamming. So what industry has done is, say, “okay, you don’t like BPA, we’ll take it out. And we’ll put in something that is, as you say, structurally, very similar chemically very similar, doing the same harm.” 

But they also did it for phthalates. And they did it for other chemicals; the flame retardants, and so on. They’ve been doing this for years. That’s common practice of the industry because there’s no law that says a chemical has to be proved safe before it’s put into the marketplace. So nothing is stopping them from substituting BPF or BPS for BPA, or DINP for DEHP, and so on and so forth. So this is how they can go about conducting business as usual with a small change which doesn’t really cost them very much. And then if you buy a BPA-free bottle, it says BPA-free, I think you’re being scammed if it contains BPF or BPS.

It’s really a form of greenwashing.

It’s dishonest. And I think the public should know about it. And that’s a problem we can talk about. How do people know about these things and hear about them? And they should be outraged.

I know I feel outraged. I was just thinking as well, aside from thinking about how this whole “Whack-a-Mole” concept and shifting things quickly to “regrettable substitutes” is a form of greenwashing and marketing. I’d like to just ask you if we backed up a little bit, and we’re talking to people who are new to this issue, how you might present it in a more general way to them? Because I feel like—I like going down the rabbit hole of talking about chemicals because I think it’s interesting and I continue to learn as much as I can about them, but I feel like your average person who’s just trying to get through a day; go to work, buy food, put food on the table for their family, care for their family may not have time to go deep into understanding or really thinking about this at all, and may not have the ability to select other packaging choices, etc, that might be less reactive. So how would you approach just laying out an overview of this issue for someone who’s new and coming to it?

So I would say the first thing to note is that we are very sensitive to very small perturbations of our hormones. Things that change our hormones, we’re very sensitive to and we need to do that because hormones are present at very low levels, and the body responds to them in very important ways – all the way from conception throughout life. 

So we depend on these hormonal signals to create proteins to function as organisms so anything that’s going to interfere with those can seriously affect our development and health. 

So if you think about how there are some natural chemicals like some mushrooms, soy, clover, which we’ve known for a long time are either estrogenic because in our bodies they act like estrogen, or maybe antiandrogenic. But what we didn’t know until relatively recently, was that manmade chemicals could also do these things and interfere with our body’s hormones.

Can you talk to that for a second? Just talk about how those hormones work and turn things on and off, because I’m not sure somebody coming to this would immediately understand.

What hormones are—they’re produced in glands. They travel through the bloodstream, and they go to a target. They go into a receptor and when they’re read out, the response is to make a change in the body. Maybe to produce more protein or to limit some function of the body. It’s what tells us when we’re hungry, and when we’re full, and increases our menstrual flow or stops it—controls our menstruation. It controls when sperm are produced, and when eggs are produced at ovulation and so on. So every part of our bodily function is controlled by hormones. Every bodily function And there are close to 100 hormones in the body. We have no idea how many of them are impacted by environmental chemicals. I have focused on the steroid hormones, those are the sex hormones, the estrogen, testosterone, to some extent, progesterone; these are the things that affect reproduction and that’s why I studied them because I studied reproduction. 

But there are others; thyroid hormone affecting immune function and ghrelin affecting appetite, and so on and so forth. Every function in the body, right? So if you have a chemical that gets into the body which is not a hormone, but is a “hormone mimic,”—another kind of scam, right?—It comes in and says, “I’m an estrogen, I’m gonna sit in this estrogen receptor, you don’t need to make any more estrogen. We’re all happy here with estrogen so you can stop making that estrogen.” That’s going to interfere with your body’s function. And it might interfere with the way the estrogen is transported, or how it passes through tissue membranes, and so on and so forth. 

So surprisingly, there are a lot of chemicals that have this ability to trick our body into thinking it should make more or less of a particular hormone. And the phthalates, where I’ve spent a lot of my time, they have this uncanny ability to decrease testosterone production. Anti-androgens they’re called because testosterone is an androgen. So these chemicals that are anti-androgens are gonna mess you up. Grown men know how important testosterone is. Women are not so aware of it, but they’ve got it too. Testosterone is important in adults for sexual function, libido, muscle mass, and all kinds of reproductive function. But the biggest effect is in utero. Maybe we can talk about that afterwards. Does that about cover?

Yeah, that covers it. But let’s talk about how they get in.

Yeah. All right. Right. So, first of all, they get in through ingestion. So what does that mean? That means eating and drinking, right? And they get in through our foods and drink. And how do they get into the foods? Well, they can get into the foods lots of ways, but one way is through the production. 

And I want to give you a really clear example. This is a small study, it was done in Eastern Europe. It was on cows that were being milked. And what they did was they compared the phthalate levels in milk from hand-milked cows—old-fashioned hand milking—to machine-milked cows. And the machine milked cows, well, you’ve seen milking machines, right? They have these tubes. Well, those tubes have, guess what? Phthalates in them. So what they did was they measured the phthalates in the milk that had come from the machine-milked cows and the hand-milked cows, and there were significantly more phthalates in the machine-milked cows. 

Now, I know you’re not surprised about that and I don’t think I wasn’t surprised. But what I was surprised by was that this was ignored. It was ignored, and no action was taken, and nobody said, “wait a minute. We have to change the tubing in these milking machines!” So that’s just one example.

Another example is the neonatal intensive care nursery. They’re—the babies are receiving their food, their nutrients, and their air basically, through tubes. And a study at Mount Sinai and other studies have shown that the amount of phthalates in the urine of the infants is proportional to the number of tubes coming into the body. 

So this was published. I think the first one was seven years ago. And now some hospitals are trying to swap out those tubes, and some are being successful. So thank goodness they’re paying attention to that because phthalates in the body of neonate, the one’s who are premature, are going to be extremely important to their development. They’re basically still in the womb, but it happens to be in a bassinet because they were born prematurely, right? 

I was gonna say I remember reading The Greening of HealthCare and looking at the work of Health Care Without Harm and Kathy Gerwig’s work with Kaiser Permanente to swap out the heavily phthalated tubing for the neonatal ward. But how does that translate into— I know, I’ve read the results of some of the research of studies done with babies exposed either in utero to these chemicals or young children exposed—but obviously, we don’t run a bunch of tests on babies and children. So so how do we know? And what is the impact that we’re seeing from the exposure to the chemicals in these plastics and plastics with newborns

Yeah, well, the best way to know what child is exposed to in utero is to see what’s in the mother’s body because we can’t get the babies’ blood or urine or so. But it turns out that what’s in the mother’s body passes the placenta and goes into the fetuses’ body

And so this model, which is now carried out in studies all over the world —many, many, many studies—is to enroll pregnant women, early in pregnancy. By the way, early is important because the most damage is done for reproductive systems early in the first trimester, so you have to get women as soon as possible after they know they’re pregnant and get them to give a urine sample. And that’s the critical thing. If you have the urine, put it in the freezer, keep it stored as minus 80 so it’s safe. And then when you have the opportunity, you can take it out, thaw it, send it to a laboratory, and find out what are the levels of phthalates in there. 

And we’ve done that in multiple studies. And what we found was that when you do that, the higher the level of certain phthalates; and we can talk about which ones they are, by the way. I didn’t finish and I only got to the food part of the exposure and we need to come back to that. But we’ve shown that when the mother was exposed to higher levels of some phthalates that the boys showed changes in their general development, the actual size of the genitals, and in some malformations that reflect having incomplete testosterone at the right time. In other words, here they’re programmed to see testosterone in a certain period in development. We know it’s a couple of weeks long. they have to have enough testosterone. If they don’t, then their genitals will not develop normally. And not only the genitals you see when the baby’s born, but also what’s inside his body—the germ cells that will produce the sperm when he is an adult. 

So we show that when a boy is born with genitals that are not completely masculine,—I don’t want to say malformed because most of them are not clear malformations, they’re just small changes. When boys are born with the phthalate syndrome, which includes having smaller genitals, when they grow up to be young men and go to try to get a woman pregnant or give us semen samples, they will have lower sperm counts and are less likely to conceive the pregnancy. So that’s a very direct link between the mother’s phthalate exposure and sperm count and infertility. 

So there are other changes in the brain. These are not less obvious, but they’re important and we’ve studied those as well. Changes in behavior, changes in socialization, and so on. And to look at that we actually wait till the children are 4, 5, 6, 7, 8, 9 years of age and test them using standard psychological tests. And here’s one example. At the age of four, the mother answers a question in Sweden in every clinic, “how many words does your child know or understand?” And it turns out when the mother has higher levels of phthalates, the number of words that a child knows is reduced significantly. That’s a brain change, right? And that study, the Soma study has a lot of data on changes in behavior, on function, socialization related to phthalates in utero. So the damage is done initially when the woman is pregnant and then plays out over the lifetime.

I know that I’ve seen it written that exposure to the chemicals in plastic has been linked to lower IQ.

Yes. That’s correct. That’s the same study, by the way—the same Swedish study.

Okay, great. Thanks. I’m sorry if I am simplifying it a little bit. If I do it incorrectly, please correct me as the scientist. We’re always trying to help translate it so that people can grasp it and understand it better. 

You weren’t finished telling me about the food exposure.

Right. Okay. So we talked about chemical phthalates that are introduced during the processing of foods. And by the way, that doesn’t have to be milk. It could be spaghetti sauce. And then there’s storage of food. So it could be when a chemical is stored in plastic, the phthalates leave the plastic and enter the food. And this is accelerated, of course when the food’s warm. But it happens.

Wait, say that one more time. Because you said when a chemical is stored in phthalates.

Plastic with phthalates, then the phthalates leave the plastic and enter the food. Okay, just like it did for the milk, or for the NICU baby. So it can be processing or storage. And the worst example, I think, is probably putting your food in a plastic container and putting that in the microwave. Because then you’re just—direct contact, it’s heat. It’s all the bad things together and the food picks up the phthalates.

Yeah, it’s something that I have come to understand. And in the years we’ve been doing this work—so Plastic Pollution Coalition is 12 years old now—but I think about, five years in, after some conversations with different scientific advisors, I began to think about the plastic Tupperware containers; particularly when you put spaghetti or anything that’s got a tomato or acid sauce in it and how that stains the plastic. And what does that mean? And so I began to realize—I feel like I’m your average person like trying to figure it out—but I started thinking, well, if the plastic is turning reddish from the tomato sauce, then does that mean that the plastic is exchanging molecules with the spaghetti and the tomato sauce? And I deduced that yes, it must be. 

And so then it got me thinking about what kind of chemicals might be coming out of the plastic container and going into the foods that I was then reheating, or heating, or cooking and eating, etc. 

Did you stop?

Oh, yeah, of course. Yeah, I’m a big, big fan of glass. Glass and ceramics. Yeah so, I try every day. Every day is a special challenge and an opportunity to figure out how to buy food or grow food and get it from the open farmer’s markets, transport it home, chop it up, prepare it, serve it, and store it with or freeze it with no plastic, which I work pretty hard to do. 

And some of my keys to that are when you want to freeze something in glass, not to fill it up all the way and do not put the lid down tight, and let it freeze for a couple days first, and then put the top down. So I have learned that the hard way.

So I’d like to just add something about your farmers market trip, which I applaud. Okay, so first of all, you’re not eating processed food, right? And you’re going to buy organic, I think, in your farmers market, if you can. 

I do. 

And so I want to just add that phthalates not only make plastic soft and flexible, they also increase absorption. And for that reason, they’re added to pesticides. Phthalates were one of the inert ingredients in pesticides. They’re no longer on the list, and I questioned why they were taken off, but I know they have this property. They help the pesticides get absorbed into the plant roots and stem and leaves. 

And that also increases the absorption of other things. For example, the hand cream that we put on, and phthalates are put in there to make that absorb better. So whenever you think absorption think phthalates. And then they also are put into retain scent and color. So that’s your lipsticks and nail polish and also smell. Anything with fragrance will have phthalates because they retain smell.

Would that be like perfumes and shampoos and conditioners and things like that in plastic?

And also fragrance in wall plugins and things of that nature.

But so you’re saying, with beauty products for example, that they’re added into the actual product. That we’re not just being dosed by the container that they’re in?

Absolutely. Absolutely. Yes, absolutely. 

When we asked our women in our study, to tell us what they used on their bodies and in their homes, and then we said, “is it fragrance-free?” And those who reported products that were not fragrance-free had higher levels of several phthalates. Significantly higher levels. 

Then we almost need like a training course for everyone how to read those lists on the back of products.

They don’t have to be included. Honestly.


And by the way, this is not our job. You know if you think about drugs, and the FDA does a pretty good job at keeping drugs pretty safe for us. There’s three levels of testing, right, and we all know that through the COVID scenario now. And they have to work. They have to be efficacious. This came after years of terrible drugs that were doing terrible harm, which we don’t have to get into. But eventually, the FDA got pretty good. And we’re pretty safe. And so we need the same kind of protection for the products in our daily lives. There is no protection from the chemicals in products in our daily lives.

And how could we affect change with that? Would that be like—we’ve all been talking about TSCA in the United States, the Toxic Substances Act, but I mean, how and where do we approach this, because it feels important to me?

It’s extremely important. And I think I see three steps: public awareness, which does not exist, and maybe this podcast will help; public awareness, working with manufacturers to recognize the need to change these products, right? Because we don’t have safe alternatives at this point. So even if people demanded a safe alternative right now it doesn’t exist for most chemicals. Not all, but most of our products. And finally, we need legislation with teeth that regulates at human-relevant scenarios. And that sounds like that’s kind of jargony. But what that means is, when products are tested in the laboratory for regulation, they have to be tested at the levels, the doses, and the mixtures that we’re exposed to. Right? We can go into that if you want. But I have to finish and say, beyond the ingestion, and we talked about the dermal absorption, I just want to say we also get these things through inhalation. So we get them through our dust, we get them through our hairspray, for example, as a great source of phthalates through inhalation. And they are off-gassing all the time into our environment. 

So you can—Carl Gustaf who did that study that you liked about the IQ; he also did a study where he put pizza boxes on the top of fridges and he collected the dust. And then he measured the phthalates in the dust and found high levels of phthalates in the dust just sitting on top of the fridge. Right? So we’re surrounded by them all the time. And HEPA, HEPA filters will help leaving your shoes at the door will help. But basically, those are band-aids for the problem that’s much, much bigger. 

Yeah, it’s been interesting just to see the studies that have come out this year about microfibers and microplastics in human placenta, both on the mother’s side and the baby’s side and in lung tissue. 

Let me ask you a question about that. It feels like this issue, and the research you’ve been doing, and your new book Count Down, and the focus around the impact of these chemicals in plastic on human fertility, but also animal fertility—It feels like it’s largely a bipartisan issue. And I was wondering if you could tell us about your #CountMeIn campaign and what sort of response you’ve received from the public.

I think what we’re seeing from public responses is that people are extremely interested and concerned. I want to recommend to you a YouTube video. I don’t know if you’ve seen it. It’s made by a very talented young man. It’s called After Skool. And After Skool tells the story that I’m talking about today. And it has been viewed, last I looked, by over a million viewers. I don’t know the coverage of the Joe Rogan show, but it was huge. And the comments were amazing. And what you hear over and over again is, “why don’t we know this?” “Why haven’t I heard this?” So, look, you’ve been working for 10 years, I’ve been working for 20 years. There’s a whole army of people dedicated—honest, hardworking, committed people working on this for a long time. But the message is not getting across. Would you agree? 

Well, I mean, I would agree on that I find whenever we present things, or just in my personal experience speaking, people always ask, “What should I do?” “What am I supposed to do?” 

So I think that the public, you know, human beings are hungry for knowledge, but they also want to have something made as easy as possible for them. And I mean, that’s really the main thing that I find. You know, I think we all work hard to communicate to the best of our ability as we learn along the way. The different parts of this issue, looking at the impact of plastic—the impact of plastic pollution—how plastic pollutes us and all living things on the planet, from extraction through manufacturing production, use, if it’s single-use very short, and then is instantly a waste management issue, often times incinerated. In fact, in the new legislation that was just signed, unfortunately, it includes incineration, or “waste-to-energy,” which is very unfortunate, because that is going to poison a lot of people. And so it’s always a question of understanding the interconnection of all of these things that I know. And talking with Dr. Pete Myers, that oftentimes, what I’ve come to understand about phthalates and bisphenols, and these chemicals is that they don’t, we don’t have to be exposed to them at a high level for them to change our bodies and impact us. But I actually want to ask you questions rather than me trying to process. I’m curious if you could talk about how you might suggest we improve regulatory measures to ensure that low doses, high doses of endocrine-disrupting chemicals aren’t being overlooked or missed altogether.

So, you brought up a very important point. That’s the low dose, low exposure scenario, which is not tested. So we’re using a testing paradigm, which is extremely old, and which assumes that if you have something bad, more of it is worse. And I like to tell this example about exercise. So exercise. There’s one extreme, which is you over-exercise. And women who over-exercise don’t menstruate. So it clearly affects reproductive function. On the other extreme, if you don’t exercise at all, if you’re a couch potato, you’re sitting around, you’re gaining weight, and so on, that will also decrease your reproductive success. And in the middle is the sweet spot, which is a moderate amount of exercise. 

And you see that also with alcohol and with lots of behaviors that there is a nonlinear, which is a technical term. Not a straight line. It’s not like more exercise is better—”up, up, up, up, no matter how high you go.” And it’s not true on the other side, “less and less and less is better,” right? It’s a curve. And you see that, right? And so that’s the way hormones react and that’s the way we should be regulating these chemicals. We have to find the harms at high doses, and then maybe there’s—apparently safe level—but maybe below that, it gets risky again, just like over-exercising will get risky as you go along that curve.

Is it like a bell curve?

Not a bell curve, no. A U-shaped curve. But it’s not a line. It’s not like one uni-directional, which is very, very old, simplistic way of thinking. 

Okay, so that’s one thing, the dose-response. The other thing is, which is really difficult, is this mixture question. So if you had your chemical levels measured right now, you would have probably close to 100 chemicals measurable in your body by the CDC or standard panels. And we know that exposure to multiple, say drugs—if you go to your doctor she wants to give you a medication, and she says, “what else are you taking?” And that’s because she knows that this new medication she’s going to give you can interact with the other medications you’re taking and may be harmful as a result. So that’s an interaction. And so regulatory agencies do not study the interaction of these chemicals in our body. So we study them one at a time. 

There’s a famous example of seven phthalates actually that at low doses—so you take low doses that don’t do any harm to rats, right? Male rats exposed, no harm. Then you put them all together in a mixture and you give that to the mother and the baby rats develop a general malformation called hypospadias. So that’s seven phthalates together, doing harm when none individually. So if you tested them individually, you would think it’s safe. That’s not how we’re exposed. So that’s another thing that we have to do with our regulatory system; we also have to test at ways we’re exposed, not just ingestion, which is the only way that’s tested. Animals are exposed orally. Animals are never tested through dermal exposure or inhalation exposure. So we don’t know what those routes do because that’s not tested. So all I’m saying is that the scenario that’s tested in the laboratory has to reflect our exposure otherwise we’re not testing what’s safe for humans.

Right. So, Shanna, I was thinking, maybe some final thoughts and we can wrap. I mean, I could talk about this—I would love to talk about this for hours with you. And I’m sure we’ll get to have more conversations, which I look forward to. But could we kind of end on what would you suggest people do to avoid phthalates? Or phthalates exposure?

Well, I think you’ve talked about a lot of it. I think maybe the first thing to do is to go through your house with a big bag. Plastic bag, probably. And dump in it as many of the plastic containers, spatulas, jars, that you can. Go to your fridge, go to your cupboard, and try to get rid of plastics from your kitchen. Try to replace them. Try to get rid of nonstick pans. By the way, we didn’t talk about that but that’s another class of things.The barriers, the PFAS chemicals, the barriers in your flame retardants and your waterproof. Try to pay attention to the material of which your product is made. Right? So what is it made of? Ask yourself that question and insofar as possible, like you said, select glass, ceramic, or metal and you’ll be much better off.

I would stress that you smell everything you use. Your cleaning products, your laundry products, your sunscreens, your cosmetics, and to the extent possible, try to get them odor-free. And don’t plug anything in the wall. And don’t hang that little pine cone in your car. And then, if you can afford it, you can try to seek out the chemicals, the products, the cosmetics, the cleaning products, the laundry products that are recommended on several of the sites. One of them is Environmental Working Group

MADE-SAFE, certainly.

MADE-SAFE, right. And go to MADE-SAFE and so on. 

So you can Google safe chemicals and see a bunch of alternatives. But by and large, these will be more expensive. So there is an environmental justice issue here that not everyone could afford to do this. So yeah, I just pay attention. I think that’s the main thing. Pay attention. Assume that everything you put in your body, in your mouth, breathe in, put on your skin can contain these chemicals.

I think you’ve just set a new bar for me. A new challenge. I need to go reconsider some things that I am currently using. So I really appreciate your time today, Shanna. We appreciate you and thank you for the work that you’re doing. It’s so important. It’s so vital and I also really appreciate your ability to incorporate comedy into all of this. Because, you know, some of it is pretty dire. It’s really we’re talking about an existential threat to life. And I feel like if we can at least laugh about it a little bit. It’s going to carry us through as we try to rise to the challenge and solve the problem.

Great. Well, thank you so much for your work and Plastic Pollution Coalition’s work on helping to solve this problem together. We’re all working on it together.

A new book published today from leading environmental and reproductive epidemiologist Shanna Swan, Ph.D. shows how chemicals in our modern environment are negatively impacting human sexuality and fertility. The book is called Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race.

The book details a major study completed in 2017 by Swan and her team of researchers. The research showed that over the past four decades, sperm counts among men in Western countries have dropped by more than 50 percent. In addition, infant boys are developing more genital abnormalities; more girls are experiencing early puberty; and adult women appear to be suffering declining egg quality and more miscarriages.

Swan says the major culprit is a class of chemicals called endocrine disruptors, which mimic the body’s hormones. These endocrine disruptors are everywhere: plastics, shampoos, cosmetics, cushions, pesticides, canned foods and A.T.M. receipts.

Count Down reveals what Swan and other researchers have learned about how both lifestyle and chemical exposures are affecting our fertility, sexual development, and general health as a species, and how each of us can reduce our exposure. 

“In some ways, the sperm-count decline is akin to where global warming was 40 years ago,” Swan told The New York Times. “The climate crisis has been accepted — at least by most people — as a real threat. My hope is that the same will happen with the reproductive turmoil that’s upon us.”

Learn more in the upcoming Plastic Pollution Coalition webinar featuring Shanna Swan Ph.D. and Pete Myers, Ph.D. founder and Chief Scientist of Environmental Health Sciences, called “Will Humanity Survive Plastic Pollution? Toxic Impact of Plastics’ Chemicals on Fertility.” Register now. 

Read an excerpt from the book here. 

Watch the Plastic Pollution Coalition webinar on Human Health & Ocean Pollution. 

Join our global Coalition. 

February 24, 2021 , 2:00 pm 3:00 pm PST

PPC February 2021 Webinar

Will Humanity Survive Plastic Pollution?
Toxic Impact of Plastics’ Chemicals on Fertility

Join us for a conversation with Shanna Swan, PhD, leading environmental and reproductive epidemiologist, and author of upcoming book Count Down: How Our Modern World is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race, and Dr. Pete Myers, Founder and Chief Scientist of Environmental Health Sciences.

The webinar will be moderated by Dianna Cohen, Co-Founder & CEO of Plastic Pollution Coalition, and will focus on how plastics and endocrine-disrupting chemicals are contributing to decreasing sperm counts and other negative effects on human sexuality and fertility in both women and men.

Date: Wednesday, February 24, 2021
Time: 2-3 p.m. PT | 5-6 p.m. ET
Click here to convert to your timezone.

Shanna Swan, PhD

Shanna H. Swan, PhD, is an award-winning scientist based at Mt. Sinai and one of the leading environmental and reproductive epidemiologists in the world. Dr. Swan has published more than 200 scientific papers and has been featured in extensive media coverage around the world. Her appearances include ABC News, NBC Nightly News, 60 Minutes, CBS News, PBS, BBC, PRI Radio, and NPR, as well as in leading magazines and newspapers, including Newsweek, The Washington Post, USA TODAY, Time, US News & World Report, The Guardian, Bloomberg News, New York Post, Chicago Tribune, Daily News (New York), Los Angeles Times, HuffPost, Daily Mail (London), New Scientist, Mental Floss, Mother Jones, New Telegraph, Euronews, and the National Post. She is author of the new book Count Down: How Our Modern World is Threatening Sperm Counts, Altering Male and Female Reproductive Development.

Pete Myers

Dr. Pete Myers

Pete Myers is founder and Chief Scientist of Environmental Health Sciences, a non-profit organization that promotes public understanding of advances in scientific research on links between the environment and health. Dr. Myers holds a doctorate in the biological sciences from UC Berkeley.

While director of the W. Alton Jones Foundation (1990-2002) he co-authored “Our Stolen Future,” a best-seller that explores how contamination threatens fetal development.

He has served on numerous non-profit boards including as Board Chair of the National Environmental Trust and Board Chair of the H. John Heinz Center for Science, Economics and the Environment.

Myers has received multiple major national and international awards, including: the Laureate Award for Outstanding Public Service from The Endocrine Society (2016), the “Champion of Environmental Health Research Award (2016) from the National Institutes of Health, and the “Distinguished Service Award (2017) from the Sierra Club.


February 24, 2021
2:00 pm – 3:00 pm PST
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Plastic Pollution Coalition
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By Pete Myers, Environmental Health News

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.”

But there is much more to this study, led by Washington State University doctoral student Tegan Horan and published in the journal PLoS Genet. The senior author on the paper, Washington State University’s Distinguished Professor of Molecular Biosciences, Patricia Hunt, is one of the world’s leading authorities on how endocrine disrupting chemicals harm the development of sperm and eggs.

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.”

Successive, constant exposure

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.

More than a dozen papers have now been published on “trans-generational epigenetic inheritance,” where exposure in a great-grandmother causes adverse effects in great-grandson—without further exposures and without changes in DNA sequence.

But crucially these experiments typically only expose one generation—the first—rather induce ongoing exposures across generations, which is the reality of human experience.

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.

Laura Vandenberg, an expert on endocrine disruption effects at the University of Massachusetts, Amherst and who did not participate in either study called Horan and Hunt’s work “an elegantly designed study that looks at several really important issues in environmental health.”

“As the authors rightly point out,” Vandenberg added via email, “over the past several decades, exposures to environmental chemicals—and estrogens in particular—have continued to rise.”

Exposure today, she added, is life-long, not episodic.

“Remarkably, the damage that is seen in any one generation gets worse and worse as more generations are exposed,” Vandenberg said. “I have never seen a study examine these different generations so beautifully – this is a tremendous amount of work!”

Long-term decline

The first paper, published Tuesday in the journal Human Reproduction, analyzes data from all studies on the topic researchers could find published in the scientific literature between 1981 and 2013.  Researchers, including Hagai Levine of the Hebrew University of Jerusalem and Shanna Swan of the Icahn School of Medicine in New York found 185 studies that sampled a total of 42,000 men across fourdecades beginning in 1973.

“20 percent of Danish men do not father children.” 
—Niels Skakkebæk,
University of Copenhagen

Declines in sperm concentration and total sperm count were “highly significant” for samples from North America, Europe, Australia and New Zealand. Those from South America, Asia and Africa were not significant, possibly a result of a much smaller sample size.

Hunt sees considerable linkage between the two studies. “Our data are showing that things get progressively worse as subsequent generations are exposed,” she said. “These large changes in human sperm count and concentration reveal that we are already well down the road.”

Niels Skakkebæk, a Danish pediatrician and researcher whose 1992 paper with Elisabeth Carlsen reporting large long-term declines in human sperm count kicked off over 20 years of debate, added: “These two new papers add significantly to existing literature on adverse trends in male reproductive health problems. Importantly, the data are in line with data on testicular cancer which is increasing worldwide.” Skakkebæk did not participate in either study.

“Here in Denmark, there is an epidemic of infertility,” Skakkebæk said. “More than 20 percent of Danish men do not father children.”

“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.”

Skakkebæk’s concerns about younger men are reinforced by some of the details of the new sperm study because it reports that men in a subgroup of the total sample 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 almost 50 percent over four decades, to 47 million sperm per milliliter. That puts counts close to what the World Health Organization considers impairment in ability fertilize an egg—40 million sperm per milliliter.

Indicator of male health?

Poor sperm count is associated with overall morbidity and mortality.

That’s the average reduction. Every average has a distribution: Some with more reduction, some less. And those who fall in the “more” category may wind up below the level where WHO considers fertilization unlikely—15 million sper
m per milliliter. The new study specifically notes that a high proportion of men from Western countries have concentrations below 40 million per milliliter.

The sperm count study raises a larger issue, beyond reductions in the ability to fertilize an egg.

“Poor sperm count is associated with overall morbidity and mortality,” the authors wrote. “A decline in sperm count might be considered as a ‘canary in the coal mine’ for male health across the lifespan. Our report of a continuing and robust decline should, therefore, trigger research into its causes, aiming for prevention.”

Are we, as suggested by Dr. vom Saal, in a “death spiral” of male infertility? And if so, what are the larger implications? Perhaps the most far-reaching, if this is true, would be what this means there will be changes in age distributions in populations in nations suffering from this spiral.

A core assumption driving economic policies around the world is that growth is essential. Populations that are declining because of infertility face big problems because economic activity depends upon have a large number of working people compared to those that are retired. Expectations for economic growth diminish.

Would further declines in male fertility undermine the assumptions that fuel faith in economic growth, as the age distribution shifts to one with more retired people and fewer working? These are vital questions that traditional demographers have largely chosen to ignore.


Levine, H, Jørgensen, N, Martino-Andrade, A, Mendiola, J, Weksler-Derri, D, Mindlis, I, Pinotti, R, Swan, SH. (2017) Temporal trends in sperm count: a systematic review and meta-regression analysis. Human Reproduction Update 1-14. 

Horan, TS, Marre, A, Hassold T, Lawson C, Hunt PA (2017) Germline and reproductive tract effects intensify in male mice with successive generations of estrogenic exposure.PLoS Genet 13(7): e1006885 

Pete Myers is founder and chief science officer of Environmental Health News, publisher of and