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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"

Many health professionals have warned for years that the antibacterial triclosan should be avoided. Triclosan is found in a large variety of personal and consumer products labeled "antibacterial" or "antimicrobial". Now a recent study gives another reason to avoid triclosan - it makes UTI (urinary tract infection) bacteria MORE resistant to antibiotics.

Scientists have been warning about triclosan (and related triclocarbon) for a while, and have asked that their use be restricted due to risks to human health, to wildlifeand its accumulation in water, land, wildlife, and humans. Not only do they persist in the environment, they are also a source of toxic and carcinogenic compounds including dioxins, chloroform, and chlorinated anilines. They are endocrine disruptors that bioaccumulate (build-up) in humans and wildlife. They are toxic to aquatic and other organisms, yet they are found in the majority of people and freshwater streams. In other words, the chemicals are all around us and in us!

More than 2000 personal and consumer products, as well as building materials, contain triclosan and triclocarban. For example, they are found in soaps, toothpastes, detergents, clothing, toys, carpets, plastics, kitchen items, and paints. According to the FDA, which is responsible for regulation of foods, drugs, cosmetics, medical devices, and similar products, there is no evidence that antibacterial soaps are more effective than nonantibacterial soap and water.

What should one do? Read labels and avoid products containing triclosan and other antimicrobials, and products labeled anti-odor, antibacterial, anti-germ, or containing Microban. No, you don't need antibacterial or anti-odor socks or cutting boards! See earlier posts on this topic (herehere, and here).

From Science Daily: Chemical added to consumer products impairs response to antibiotic treatment

Grocery store aisles are stocked with products that promise to kill bacteria. People snap up those items to protect themselves from the germs that make them sick. However, new research from Washington University in St. Louis finds that a chemical that is supposed to kill bacteria is actually making them stronger and more capable of surviving antibiotic treatment.  ...continue reading "Avoid Using Products With the Antimicrobial Triclosan"

Some good news for women and breast cancer. We are all exposed to endocrine disruptors  around us - such as in personal care items, some household items, some medical devices and medications, plastic raincoats, and vinyl flooring. Phthalates, which are endocrine disruptors, are used as plasticizers in many of these products. We can lower our exposure to phthalates, but can't totally eliminate it. So a big question is: Is exposure to phthalates linked to breast cancer?

Animal and laboratory studies suggest that a number of phthalates have carcinogenic effects (cancer causing), but several retrospective studies of women had mixed results regarding whether higher phthalate levels are associated with breast cancer or not. But now a large study (the Women's Health Initiative) that followed postmenopausal women for 2 decades has found that phthalate levels are not associated with an increased risk of breast cancer.

The 1257 women (average age 62 1/2 years at the start) in the study gave either 2 or 3 urine samples (once a year) during the first 2 or 3 years of the study, and the urine was analyzed for a number of phthalates. Then the women were followed for 19 years. The researchers found some "suggestive associations", but nothing significant. Whew... We can breathe sigh of relief.

However, there are some real problems with the study. While it does not look likely that phthalates have a large effect, smaller associations are possible, which the researchers discuss.

1) One big problem is that phthalates are rapidly metabolized and excreted from the body, so that the levels can vary tremendously from one point in time to another. (Half of phthalate metabolites are excreted in urine within 12 to 24 hours of exposure.) And the researchers did find that "phthalate biomarker concentrations exhibited high within-person variability over a 3 year period".  More urine samples should have been taken from the women - not just one a year for 2 or 3 years. This study did not look at who routinely got exposed to high levels of phthalates and who wasn't. Half of phthalate metabolites are excreted in urine within 12 to 24 hours of exposure. Just having a week with lots of fast food could raise phthalate levels (the chemicals leach in from the packaging). See why only one measurement a year is inadequate?

2) Another big problem is that most of the postmenopausal women - whether with breast cancer or not, were using hormone therapy - in the past or during the study. As the researchers point out: "Because phthalates are far less estrogenic than hormone therapy formulations, it is possible that hormone therapy use may mask any true effect of phthalate exposure on breast cancer risk." 3) And the last big issue to think about is that this study did not look at early life exposures to phthalates, such as during puberty when the breasts are developing. Other studies suggest that exposure to endocrine disrupting chemicals are important during critical periods of life, especially earlier in life (e.g. adolescence). Looking just at phthalate exposure of postmenopausal women may be too late.

According to studies and the CDCalmost everyone in the United States is exposed to phthalates in varying degrees, especially by eating and drinking food and liquid that has come in contact with containers and products containing the chemicals, and by inhaling indoor air that has phthalates in the dust. Adult women tend to have higher exposure to certain phthalates (it's measured in the urine) that are used in soaps, body washes, shampoos, cosmetics, and similar personal care products.  ...continue reading "Breast Cancer and Endocrine Disruptors"

The following is a really nice article about endocrine disruptors (chemicals that can interfere with the body's hormonal system). Journalist Hillary Brueck writes about where they are found (all around us!), some of the many negative health effects, and about NYU physician and researcher Dr. Leonardo Trasande and his new book: "Sicker, Fatter, Poorer: The Urgent Threat of Hormone-Disrupting Chemicals to Our Health and Future ... and What We Can Do About It." Also, some things we can do to lower our exposure to endocrine disruptors.

By the way, once again Europe is ahead of the US in dealing with this problem. Excerpts from Business Insider: A toxic-chemicals expert is sounding the alarm about 4 cancer-linked chemicals that could be making us sicker and fatter

Through the course of a single day, your hands, mouth, and body come in contact with countless pieces of paper, plastic, fabric, and furniture. You probably don't think about the chemicals these substances might harbor, or consider that they have a drug-like effect on health. But some do. They can make metabolisms slow down, subtly lower IQs, contribute to ADHD in children, and mess with sperm counts in men.

They're called "endocrine disruptors," and they're around us all the time. The chemicals change how our bodies work by shifting the way hormones operate, according to Leo Trasande, a pediatrician and public-health researcher at NYU Langone Health. "Hormones are the basic signaling molecules in our body that take on so many actions for practically every organ system," Trasande told Business Insider. "And endocrine disruptors are synthetic chemicals that scramble those signals, contributing to disease and disability."

In his new book, "Sicker, Fatter, Poorer: The Urgent Threat of Hormone-Disrupting Chemicals to Our Health and Future ... and What We Can Do About It," Trasande lays out the four big categories of endocrine disruptors he's most concerned about, based on evidence from scientific studies and observations in his patients. They are: Bisphenols, like BPA, which are often found in the linings of aluminum-canned food and drinks and on cash-register receipts. Brominated flame retardants that are in some carpets, furniture, and clothing. Synthetic pesticides on food. "Plasticizer chemicals" called phthalates that show up in plastic food packaging, lotions, and cosmetics.  ...continue reading "New Book Warning Us About Endocrine Disruptors"

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.]

Dental floss coated with a "non-stick coating" has long been a concern of mine. Do the Teflon-like chemicals get into the person when a person is flossing teeth? These chemical compounds (called per- and polyfluoroalkyl substances or PFASs) are linked to health problems (e.g. kidney and testicular cancer, semen quality, thyroid disease, immune system effects, and lowered sex and growth hormones in children) - so you want to avoid them if possible. Well, it turns out these chemicals are shed into the person's mouth when flossing and can be measured in a person's blood. Bottom line: avoid non-stick smooth dental floss such as Oral-B Glide dental floss (or when the dental floss label brags that it is similar to Glide dental floss). Use plain waxed or unwaxed floss instead.

Per- and polyfluoroalkyl substances (PFASs) are a group of chemicals used in a wide variety of consumer products because they have water- and grease-resistant properties. They are used in nonstick cookware, in food packaging (especially the paper wrappers and cardboard containers) , stain-resistant carpets, furniture, floor waxes, textiles, water-proof and stain-resistant clothing (such as Gore-tex fabric), and performance gear. How do they get into us? Some ways: the chemicals can migrate out of food packaging into food, or can be released into the air and dust from carpets and upholstery treated with stain-resistant coatings. PFASs have been detected in water, soil, and in the bodies of almost all Americans!

This study (and others)  found that higher levels of  these chemicals in the body occur with the following: frequent consumption of prepared food in coated cardboard containers, having stain-resistant carpets or furniture, using Oral-B Glide dental floss, and living in a city served by a PFAS-contaminated water supply. It may not be possible to totally avoid all PFASs, but one can lower exposure to them (for example, don't have stain-resistant carpets in the house or apartment, and try to eat less fast-food). From Medical Xpress:

Dental flossing and other behaviors linked with higher levels of toxic chemicals in the body        ...continue reading "Some Types of Dental Floss Should Be Avoided"

Once again research finds that endocrine disruptors are associated with health effects - this time with earlier puberty in girlsEndocrine disruptors are chemicals that interfere with the body's endocrine (or hormone) systems and can produce all sorts of negative health effects, including all sorts of reproductive problems in both males and females. Phthalates, parabens, and phenols (all used in common everyday products) are examples of endocrine disruptors.

The researchers asked the question: Is a baby's exposure before birth or exposure around the time of puberty (peripuberty) to phthalates, parabens, and phenols (which are found in personal care products) associated with the timing of when he or she starts puberty? In other words, does the mother's exposure to these chemicals during pregnancy have an effect on the fetus, which then has an effect years later on the child's puberty? And how about peripubertal exposure? The answer is a strong YES for girls, and minimal effect on boys (but boys did have earlier genital development with propyl paraben exposure).

What is scary is that almost all women (and men) are exposed to these chemicals - which can be measured in the urine. Studies find these chemicals in over 96% of American women. What to do?  One can't totally escape these chemicals, but one can really minimize exposure by reading labels and avoiding personal care products that list phthalates, parabens, phenols, as well as Triclosan (found in some anti-bacterial soaps). Avoid products that include "fragrances" or "scents" (those have a multitude of chemicals in them, including endocrine disruptors). Avoid air fresheners, dryer sheets, scented candles, room deodorizers, essential oils (lavender, tea tree oil). Buy "unscented" or "fragrance free" products.

The good news is that once a person avoids these chemicals, the levels in the body go down. So it's worth the effort minimizing exposure to them. By the way, animal studies find numerous reproductive effects from these chemicals, including timing of puberty. From Medical Xpress:

Chemicals in personal care and household products linked to earlier puberty in girls

Chemicals that are widely used in personal care and household products are linked to girls entering puberty at earlier ages, according to findings from a long-running study of mothers and children published today. The study in Human Reproduction, one of the world's leading reproductive medicine journals, found that chemicals such as phthalates, parabens and phenols were all associated with earlier puberty in girls, although there was no similar association observed in boys.   

...continue reading "Personal Care Products and Puberty"

Studies finding health effects from BPA keep appearing. BPA (bisphenol-A) is a chemical used in many everyday products (e.g. the lining of soda and food cans, store receipts) and so almost all humans are exposed to it daily. Researchers are getting increasingly worried about BPA and related chemicals (including substitutes for BPA such as BPS) because they are endocrine (hormone) disruptors with health effects in humans and animals. This chemical is so widely used that more than 7 billion metric tons of it are produced annually throughout the world.

Unfortunately the US government keeps agreeing with the chemical industry that the chemical is "safe", and disregarding the results of studies finding health effects (reproductive effects, obesity, etc). Of course the chemical industry is fighting tooth and nail to discredit studies done by independent researchers - a lot of money is at stake.

The following are excerpts from an article describing the latest study finding health effects from low dose exposure from BPA - it altered the amount of insulin released by the person (and so perhaps influencing the development of type 2 diabetes). What was worrisome is that the dose is considered "safe" by the US government - and in the study people were exposed to it once, while in real life humans are exposed to such doses multiple times daily.

The good news is that BPA is excreted within a day, but the bad news is that we the keep being exposed to it. By the way, substitutes for BPA (such as BPS) are just as bad, and are also endocrine disruptors - after all, they're all related chemically. So buying BPA-free canned food or plastic won't help a person avoid endocrine disruptors - these also leach into food. From an article written by Lynn Peeples at Environmental Health News:

In a scientific first, researchers gave people BPA — and saw a link to precursor of type 2 diabetes

In a scientific first, researchers gave people BPA — and saw a link to precursor of type 2 diabetesThe controversial study suggests that BPA exposure deemed safe by the feds could alter the amount of insulin released and elevate people's type 2 diabetes risk. 

A first-of-its-kind study of a small group of people exposed to a very small amount of bisphenol-A (BPA) is raising questions about the federal government's stance that low doses of the common chemical are safe — as well as the ethics of conducting such an experiment on humans.

...continue reading "Exposure to BPA Has An Effect on Insulin Levels"

Endocrine disruptors are in the news frequently nowadays. These are chemicals that interfere with the body's endocrine (or hormone) systems and can produce all sorts of negative health effects, including all sorts of reproductive problems in both males and females. Phthalates and parabens (both used in common everyday products) are examples of endocrine disruptors.

The latest is that a study conducted in Pakistan found that women with endometriosis had high levels of a common endocrine disruptor - a phthalate known as diethylhexyl phthalate (DEHP), which is used in many everyday products. Healthy women without endometriosis did not have detectable levels of DEHP in their serum (blood) in this study. The researchers say that these results suggest that the phthalate DEHP, which is used in plastics, has a contributing role in the development of endometriosis.

Endometriosis is an often painful condition in which tissue that normally lines the inside of the uterus (the endometrium) grows outside the uterus. Symptoms may include abdominal pain, heavy periods, and infertility.

Phthalates are used as plasticizers -  substances added to plastics to increase their flexibility, transparency, durability, and longevity. They are used in many consumer products, including in household furnishings, soft vinyl toys, flooring,medical equipment, air fresheners, cosmetics, perfumes, food packaging, medicine, and insecticides. Some ways humans are exposed to DEHP is from eating processed food (which contains some DEHP that has leached from food processing machines and packaging materials) and from applying personal care and cosmetic products to the skin.

Other studies have also found that DEHP levels are significantly higher in women with endometriosis compared to women without endometriosis. Interestingly, in this study - those with more advanced stages of endometriosis also tended to have the highest levels of DEHP. Excerpts from the study by  Sadia Nazir et al from the Journal of Human Reproductive Sciences:

Women Diagnosed with Endometriosis Show High Serum Levels of Diethyl Hexyl Phthalate

Abstract: Endometriosis is one of the common causes of infertility with very diverse etiology. In modern lifestyle, humans are exposed to several endocrine-disrupting chemicals (EDCs) which may lead to reproductive disturbances. Diethyl hexyl phthalate (DEHP) is one of the common EDCs to which women are exposed by the use of cosmetics, perfumes, food packaging, medicine, and insecticides.

...continue reading "Common Chemicals and Endometriosis"

The following article in a popular magazine follows up on research that came out last year about the alarming steep decline in male sperm counts and sperm concentration over the past few decades. This is true for the U.S., Europe, Australia, New Zealand, and it is thought world wide. The article discusses the causes: environmental chemicals and plastics, especially those that are endocrine disruptors (they disrupt a person's hormones!). These chemicals are all around us, and we all have some in our bodies (but the amounts and types vary from person to person). Some examples of such chemicals are parabens, phthalates, BPA and BPA substitutes.

Even though there are effects from these chemicals throughout life, some of the worst effects from these chemicals seem to be during pregnancy - with a big effect on the developing male fetus. Testosterone levels in men are also droppingBottom line: males are becoming "less male", especially due to their exposure to all these chemicals when they are developing before birth (fetal exposure). Since it is getting worse with every generation of males, the concern is that soon males may be unable to father children because their sperm count will be too low - infertility. Dogs are experiencing the same decline in fertility!

Why isn't there more concern over this? What can we do? We all use and need plastic products, but we need to use safer chemicals in products, ones that won't mimic hormones and have endocrine disrupting effects. Remember, these chemicals have more effects on humans than just sperm quality (here and here). While you can't totally avoid plastics and endocrine disrupting chemicals, you can definitely lower your exposure. And it's most important before conception (levels of these chemicals in both parents), during pregnancy, and during childhood.

Do go read the whole article. Excerpts from Daniel Noah Halpern's article in GQ: Sperm Count Zero

A strange thing has happened to men over the past few decades: We’ve become increasingly infertile, so much so that within a generation we may lose the ability to reproduce entirely. What’s causing this mysterious drop in sperm counts—and is there any way to reverse it before it’s too late? 

Last summer a group of researchers from Hebrew University and Mount Sinai medical school published a study showing that sperm counts in the U.S., Europe, Australia, and New Zealand have fallen by more than 50 percent over the past four decades. (They judged data from the rest of the world to be insufficient to draw conclusions from, but there are studies suggesting that the trend could be worldwide.) That is to say: We are producing half the sperm our grandfathers did. We are half as fertile.

The Hebrew University/Mount Sinai paper was a meta-analysis by a team of epidemiologists, clinicians, and researchers that culled data from 185 studies, which examined semen from almost 43,000 men. It showed that the human race is apparently on a trend line toward becoming unable to reproduce itself. Sperm counts went from 99 million sperm per milliliter of semen in 1973 to 47 million per milliliter in 2011, and the decline has been accelerating. Would 40 more years—or fewer—bring us all the way to zero? 

I called Shanna H. Swan, a reproductive epidemiologist at Mount Sinai and one of the lead authors of the study, to ask if there was any good news hiding behind those brutal numbers. Were we really at risk of extinction? She failed to comfort me. “The What Does It Mean question means extrapolating beyond your data,” Swan said, “which is always a tricky thing. But you can ask, ‘What does it take? When is a species in danger? When is a species threatened?’ And we are definitely on that path.” That path, in its darkest reaches, leads to no more naturally conceived babies and potentially to no babies at all—and the final generation of Homo sapiens will roam the earth knowing they will be the last of their kind.

...continue reading "Will All Men Eventually Be Infertile?"