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 Uh oh....A recent study found that every baby teether tested (and they tested 59 teethers), including all those labeled "BPA free", leached various parabens, bisphenols (including BPA or bisphenol A), and other endocrine disrupting chemicals. Infants chew and suck teethers to soothe the pain from their teeth emerging in the first year of life.

The researchers tested for 26 chemicals in three different types of teethers (solid plastic, gel-filled, and water-filled), and found parabens and bisphenols leaching from all of them. To see what leaches from the teethers, they placed the teethers into water - this is similar to what happens when babies mouth teethers and their saliva is exposed to chemicals in the teethers. The gel filled teethers leached the most chemicals overall. Even though 48 of the 59 teethers were labeled “BPA-free,” the results showed that the labels were misleading, because in this study BPA migrated (leached out) from all the teethers.

Endocrine disrupting chemicals can interfere with natural hormone function and are linked to a wide assortment of health problems (see posts on them). Even though the levels of the chemicals found were low, it is important to remember that effects from endocrine disrupting chemicals (hormone disruptors) are from very low levels. So exposing developing infants to these chemicals is of concern. What was disturbing is that these study results were far worse than a small study of teethers in Europe where the standards regarding endocrine disrupting chemicals are stricter than in the US. What should be done? Manufacturers should design products without using problem ingredients right from the start. Problem solved! From Science Daily:

Baby teethers soothe, but many contain low levels of BPA

Bisphenol-A (BPA), parabens and antimicrobials are widely used in personal care products and plastics. The U.S. and other governments have banned or restricted some of these compounds' use in certain products for babies and kids. But the compounds' presence in and leaching from teethers hasn't been thoroughly investigated. Now a study in the ACS journal Environmental Science & Technology reports that all tested plastic teethers contained BPA and other endocrine-disruptors that leached at low levels.

Studies have shown that in animals, endocrine-disrupting compounds (EDCs) -- which include BPA, parabens and antimicrobials -- can potentially interfere with hormones and have harmful developmental, reproductive and neurological effects. As a result, the European Commission in 2011 restricted the use of BPA in baby bottles. The U.S. followed suit a year later, banning it from baby bottles, and also from children's drinking cups....But very few if any studies have investigated whether the compounds are used to make teethers and if the compounds leach out of these products, which are designed to soothe babies' gums when their teeth come in. Kurunthachalam Kannan and colleagues wanted to see if the products contained EDCs and if the compounds could migrate out.

The researchers analyzed 59 solid, gel-filled or water-filled teethers purchased online in the U.S. for 26 potential endocrine-disrupting chemicals. Although most of the products were labeled BPA-free or non-toxic, all of them contained BPA. In addition, the researchers detected a range of different parabens and the antimicrobials triclosan and triclocarban in most of the teethers....Based on estimates of average use time and the body weight of a 12-month-old baby, calculations suggest that exposure to BPA and other regulated EDCs in teethers would be lower than the European standards for temporary tolerable daily intake levels. However, these thresholds are set for individual compounds. Current regulations do not account for the accumulation of multiple EDCs, note the researchers. Additionally, not all chemicals measured in the study are regulated.

Many articles have been written about endocrine disrupting chemicals and the numerous health problems they're linked to (see posts on them). It's been known for decades that endocrine-disrupting chemicals pose a danger to human health because the compounds can interfere with natural hormone function. Chemical exposure occurs through routine contact with plastic bottles, vinyl items, toys, food cans, cosmetics, flame retardants, and other consumer products containing "endocrine-disrupting chemicals". We ingest, breathe them in (inhalation), or absorb them through the skin as consumer products are used and also as consumer products break down (the dust).

Finally a study examines the financial cost of these chemicals - an estimate of more than $340 billion annually due to health care costs and lost wages (the authors say this is a conservative estimate). What can ordinary people do to lower their exposure to these chemicals? Avoid the use of pesticides in the home, lawns, and gardens. Eat as much organic foods as possible. Avoid buying food in cans, including soda. Store food in glass and stainless steel containers. Avoid microwaving in plastic containers (use glass instead). Avoid plastic bottles with the numbers 3, 6, and 7 on the bottom. Avoid vinyl items such as vinyl shower curtains and vinyl toys. Avoid fragrances (get unscented products). Read labels on lotions, shampoos, soaps, make-up - avoid phthalates and parabens. Avoid flame retardants (check the labels on new upholstered furniture). Avoid non-stick pots, avoid stain-repellant items, avoid air fresheners and dryer sheets. And that's just a partial list....From Environmental Health News:

Toxic economy: Common chemicals cost US billions every year

Exposure to chemicals in pesticides, toys, makeup, food packaging and detergents costs the U.S. more than $340 billion annually due to health care costs and lost wages, according to a new analysis. The chemicals, known as endocrine disruptors, impact how human hormones function and have been linked to a variety of health problems such as impaired brain development, lower IQs, behavior problems, infertility, birth defects, obesity and diabetes. The findings, researchers say, "document the urgent public threat posed by endocrine disrupting chemicals.”   ...continue reading "Exposure to Common Chemicals Costs the US $340 Billion Each Year"

More bad news about BPA (bisphenol A) - an endocrine disrupter linked to a number of health problems, including reproductive disorders (here, here, and here). A new study has lent support for a  link between bisphenol A (BPA) exposure during pregnancy and later breast cancer. BPA can cross the placenta in the womb, and so expose the fetus, it has been found in placental tissue, and newborns can be exposed through breastfeeding. BPA is found in the urine of about 95% of the U.S. population.

It's hard to avoid BPA because it's found in so many products, but a person can lower exposure to it by avoiding canned products (it's in the can linings), as well as plastic bottles and containers, microwaving or heating food in plastic containers, and fast food (it's in the packaging and leaches into the food) . Glass and stainless steel is OK for storing food. By the way, BPA substitutes such as BPS  and BPSIP have the same negative health effects (because they're chemically similar) - so also avoid "BPA-free" products. From Endocrine News;

A Pervasive Threat: The Danger of in utero BPA Exposure

A new study presented at ENDO [Endocrine Society] 2016 revealed a possible link between bisphenol A exposure in utero to breast cancer later in life. In the process, the researchers created a new bioassay that can test chemicals much faster than typical animal studies. Almost every single person alive today has detectable amounts of endocrine-disrupting chemicals (EDCs) in his or her body, according to the 2015 joint Endocrine Society/IPEN publication Introduction to Endocrine Disrupting Chemicals (EDCs): A Guide for Public Interest Organizations and Policy-Makers.

These EDCs — phthalates (plasticizers), bisphenol A (BPA), polychlorinated biphenyls (PCBs), and others, in their bodies — are hormone-like industrial chemicals that did not even exist 100 or so years ago. Studies on human populations consistently demonstrate associations between the presence of certain chemicals and higher risks of endocrine disorders such as impaired fertility, diabetes, obesity, cardiovascular disorders, and cancer.

The xenoestrogen BPA is especially prevalent as a component used in rigid plastic products such as compact discs, food and beverage containers, food and formula can linings, and glossy paper receipts. In the case of food containers, when they are heated or scratched, the BPA can seep out into the food and then be ingested. BPA also escapes from water pipes, dental materials, cosmetics, and household products among others and is released into the environment or directly consumed. According to research, such exposures help account for why BPA has been found in the urine of a representative sample of 95% of the U.S. population.

Notably, BPA can cross the placenta in the womb, indirectly exposing the fetus — it has been found in both maternal and fetal serum as well as neonatal placental tissue. Newborns can also be directly exposed through breastfeeding.

The results of a study presented at ENDO 2016 provide compelling support for the idea that fetal exposure to BPA might increase risk for development of breast cancer in adulthood; in fact, it may explain why overall incidence increased in the 20th century. Lucia Speroni, PhD, a research associate and member of the Soto-Sonnenschein lab at Tufts University School of Medicine in Boston and the study’s lead investigator, reports, “We found that BPA acts directly on the mammary gland and that this effect is dose dependent: A low dose significantly increased ductal growth, whereas a high dose decreased it.”

“Because these effects are similar to those found when exposing the fetus through its mother, our experiment suggests that BPA acts directly on the fetal mammary gland, causing changes to the tissue that have been associated with a higher predisposition to breast cancer later in life,” Speroni explains. In replicating the process of mammary gland development in vitro, this method additionally allows for live observation throughout the whole process.....The lab team had previously shown that the most harmful time for exposure to BPA is during fetal development by causing alterations in the developing mammary gland.

Recent research examined levels of endocrine disruptors called phthalates in people eating fast food. Researchers found evidence of a dose–response relationship between fast food intake and exposure to phthalates - the more one eats fast food, the more phthalates (actually metabolites of the phthalates) can be measured in the person's urine. Fast food consumers had higher urinary levels of the phthalates DEHP, DiNP, and BPA than those not consuming fast food (even though the differences in levels of BPA among groups were "non-significant"). This is of concern because these endocrine disruptors are linked to a number of health problems. (Earlier discussion of this research.)

DEHP, DiNP, and BPA are detected in over 90% of the population in the US, but since there are many health concerns - it is better to have lower levels than higher levels. (Zero levels would be best). Note that phthalates and BPA are quickly metabolized and excreted in urine, with elimination half-lives of less than 24 hr - which is why the study looked at what had been eaten in the last 24 hours. But this also shows that one can quickly reduce their levels in the body.

Some possible sources of phthalate contamination in fast food are: PVC tubing, vinyl gloves used for food handling, and food packaging, including beverage cans - the chemicals leach or migrate out into the food and then are ingested. (More on chemicals migrating from containers to food), Fast food was defined as food obtained from restaurants without waiter service and from pizza restaurants, as well as all carry-out and delivery food. Another excellent reason to cut back on fast food (like we don't have enough reasons already!). The following news report discusses the research. From Environmental Health Perspectives:

Phthalates in Fast Food: A Potential Dietary Source of Exposure

Many research studies have surveyed nutritional habits, but fewer have studied how food processing and packaging might introduce unwanted chemicals into foods. In this issue of EHP, researchers report that fast food consumption appears to be one source of exposure to the chemicals di(2-ethylhexyl) phthalate (DEHP) and diisononyl phthalate (DiNP).1

The authors used data from the National Health and Nutrition Examination Survey (NHANES) to estimate the percentage of individuals’ calories that came from fast food, fat intake attributable to fast food consumption, and fast food intake by food group. During NHANES interviews, respondents had reported their diet from the preceding 24 hours. Fast food was defined as food obtained from restaurants without waiter service and from pizza restaurants, as well as all carryout and delivery food.2 ....The final study population included nearly 9,000 people aged 6 years or older. Approximately one-third of people surveyed had eaten fast food in the preceding 24 hours. Study participants who ate fast food were more likely to be male, under age 40, and non-Hispanic black, and to have higher total calorie and total fat intake from fast food, compared with the general population.1

Fast food consumers had higher urinary levels of DEHP, DiNP, and BPA than non-consumers, although the differences in average urinary levels were small and for BPA were non-significant. When fast food intake was categorized by food group, DEHP metabolites were associated with intake of grains and “other” (a category that included vegetables, condiments, potato items, beverages, and more). DiNP metabolites were associated with intake of meat and grains.1

The authors also found that the associations between phthalates and fast food were not uniform across the population.1They speculate that the pronounced association they saw between fast food consumption and DEHP in black consumers could reflect higher overall consumption of fast food and/or different food choices among this population. Prior research suggests that predominately black neighborhoods in urban areas have a greater density of fast food restaurants than white neighborhoods.3

The authors point to PVC tubing, vinyl gloves used for food handling, and food packaging as possible sources of phthalate contamination in fast food. DEHP is a ubiquitous high-molecular-weight phthalate that has been removed from some products due to concerns about potential adverse health effects.5 In some cases it is being replaced with DiNP.2

The related Environmental Health Perspectives research article:  Recent Fast Food Consumption and Bisphenol A and Phthalates Exposures among the U.S. Population in NHANES, 2003–2010

Experimental animal studies demonstrate that DEHP and DiNP have endocrine-disrupting properties because of their anti-androgenic effects on the male reproductive system (National Research Council 2008). Human exposure to DEHP has been associated with adverse reproductive, neurobehavioral, and respiratory outcomes in children (Braun et al. 2013; Ejaredar et al. 2015) and metabolic disease risk factors such as insulin resistance in adolescents and adults (James-Todd et al. 2012; Attina and Trasande 2015). Though epidemiologic evidence of DiNP is less complete, recent studies report associations between exposure and similar health outcomes including adverse respiratory and metabolic outcomes in children (Bertelsen et al. 2013; Attina and Trasande 2015). BPA is also a suspected endocrine disrupter, and experimental and human evidence suggest that BPA is a reproductive toxicant (Peretz et al. 2014). In addition, prenatal BPA exposure has also been associated with adverse neurobehavioral outcomes in children (Mustieles et al. 2015).

Given the concern over chemical toxicity, it is important to identify modifiable sources of exposure that may be targeted for exposure reduction strategies. Simulated exposure modeling, observational epidemiologic studies, and intervention studies all suggest that diet is an important exposure pathway for both high-molecular-weight phthalates and BPA.....Phthalates have been shown to leach into food from PVC in materials like tubing used in the milking process, lid gaskets, food preparation gloves, conveyor belts and food packaging materials (Cao 2010;Serrano et al. 2014). In fact, an intervention study reported that urinary BPA and DEHP were reduced by 66% and 53–56%, respectively, when participants’ diets were restricted to food with limited packaging (Rudel et al. 2011). Foods high in fat, such as dairy and meat, may be more contaminated by high-molecular-weight phthalates that are more lipophilic such as DEHP (Serrano et al. 2014). Fast food may be an important source of exposure to phthalates and BPA because it is highly processed, packaged, and handled.

Many of us grew up having silver colored dental fillings (called dental amalgam) in our teeth. Dental amalgam has been used for over 150 years for the treatment of dental cavities (caries) because it is durable, easy to use, and affordable. But it is composed of about 50% elemental mercury (Hg) and so it may release a certain amount of mercury both during the time the cavity is filled and afterward with normal wear. Mercury can cause adverse health effects, such as effects on the central nervous system, kidneys, and immune system. Human mercury exposure also occurs through the consumption of mercury (MeHg) contaminated seafood.

Recently many dentists switched to the use of the composite resins, which are mercury-free alternative materials. However, these can release can release small quantities of bisphenol A (BPA) when applied and as they degrade in the mouth. BPA is an endocrine disruptor, has been found to cause various adverse health effects, including reproductive effects, and can be measured in urine. Which raised the question, do persons with composite resin fillings have elevated BPA in their bodies?

This study examined 14,703 subjects who were divided into three groups based on the number of dental surface restorations (DSR): 0, 1–8, or greater than 8. Dental surface restorations applies to fillings, and not crowns. Note that a tooth's surface can have 5 surfaces (in molars and pre-molars), so 8 filled surfaces can be fewer than 8 teeth with fillings. (It's not the number of fillings, but the surface area they occupy - so the Science Daily article title is misleading.)

They found that the more dental surface restorations a person has, the higher the levels of mercury in the blood. But they found no association between dental surface restorations and urinary BPA. These results are reassuring for those with fillings made of composite resins, but not for people with fillings of dental amalgam. Note: DSR are Dental Surface Restorations, THg is blood total mercury, IHG is inorganic mercury, and MeHg is methyl mercury (typically from seafood). From Science Daily:

Have more than eight dental fillings? It could increase the mercury levels in your blood

Dental surface restorations composed of dental amalgam, a mixture of mercury, silver, tin and other metals, significantly contribute to prolonged mercury levels in the body, according to new research from the University of Georgia's department of environmental health science in the College of Public Health.This research, which analyzed data from nearly 15,000 individuals, is the first to demonstrate a relationship between dental fillings and mercury exposure in a nationally representative population.  ...continue reading "Dental Fillings and Mercury Levels"

Ten chemicals suspected or known to harm human health are present in more than 90% of U.S. household dust samples, according to a new study. The research adds to a growing body of evidence showing the dangers posed by exposure to chemicals we are exposed to on a daily basis. The chemicals come from a variety of household goods, including toys, cosmetics, personal care products, furniture, electronics, nonstick cookware, food packaging, floor coverings, some clothing (e.g., stain resistant), building materials, and cleaning products. How do the chemicals get into the dust? The chemicals can leach, migrate, abrade, or off-gas from the products, which winds up in the dust and  results in human exposure. (That's right:  vacuum a lot and wash your hands a lot, and try to avoid or cut  back use of products with these chemicals,)

What was found in the dust? The main chemicals were: phthalates — a group of chemicals that includes DEP, DEHP, DNBP and DIBP (these were present in the highest concentrations),  highly fluorinated chemicals (HFCs), flame retardants (both old and newer replacement ones), synthetic fragrances, and phenols. These chemicals are known to have various adverse health effects, including endocrine disruption, cancer, neurological, immune, and developmental effects. (See posts on endocrine disruptors and flame retardants) Studies typically study one chemical at a time, but household dust contains MIXTURES of these chemicals with effects unknown. How does it get into us? Inhalation, ingestion, and through skin contact. And while the levels we are exposed to may be low, research is showing that even low level exposure can have adverse health effects. From Medical Xpress:

Potentially harmful chemicals widespread in household dust

Household dust exposes people to a wide range of toxic chemicals from everyday products, according to a study led by researchers at Milken Institute School of Public Health at the George Washington University. The multi-institutional team conducted a first-of-a-kind meta-analysis, compiling data from dust samples collected throughout the United States to identify the top ten toxic chemicals commonly found in dust. They found that DEHP, a chemical belonging to a hazardous class called phthalates, was number one on that list. In addition, the researchers found that phthalates overall were found at the highest levels in dust followed by phenols and flame retardant chemicals....."The findings suggest that people, and especially children, are exposed on a daily basis to multiple chemicals in dust that are linked to serious health problems." ...continue reading "What’s In Your Household Dust?"

Over the years I have read about some oils, especially lavender and tea tree oils,  as having hormone altering (endocrine disrupting) effects when used over prolonged periods of time or when someone is "chronically exposed". Especially worrisome was the possible estrogenic effects of lavender oils in shampoos, lotions, and soaps on developing children - especially boys (prolonged use leading to the development of breasts in some boys!). I just read a recently published journal study (with very interesting comments at the end), and an article in WebMD about this same topic. The condition of early breast development is called prepubertal gynecomastia in boys and thelarche in girls.

As you can imagine, the industry (Australian Tea Tree Industry Association and Research Institute for Fragrance Materials Inc) calls such research  "poor science". Of course industry sponsored "research" never ever finds any problems (because any "problems" would impact the big $$ from the sale of those products). In fact, I would be skeptical of any industry sponsored research in this area - it is not truly independent, unbiased research if they "have to" and "want to" find no problems. So when you do read industry research, also read the rebuttals by independent scientists and doctors.

Bottom line: No matter the age, avoid prolonged use of lavender and tea tree oil in personal care products, including "aromatherapy" -  especially important for children and pregnant women. The good news is that the development of breasts in young children is reversible when use of the product is stopped. But better to avoid such products (including Agua de Violetas) on children in the first place. Instead use unscented personal care products.

From WebMD:  Are Tea Tree and Lavender Oils Safe for Kids?

Tea tree and lavender essential oils are popular ingredients in personal care and household products, including many aimed at children. But can the ingredients, often promoted as “natural” alternatives, trigger abnormal breast growth in boys and girls? A few small studies suggest that frequently using lotions, shampoos, styling gels, and even a certain cologne containing lavender and tea tree oils may cause breast growth in boys, also known as gynecomastia, along with breast growth in girls as young as 4 or 5

Other studies have not reached the same conclusions, and the cases appear to be rare. In addition, scientific research into most natural products is scant. The FDA doesn’t oversee essential oils unless they are intended for use in a drug, making it challenging to know how safe and effective these products are....Lavender and tea tree oils are among the most commonly used essential oils used. Although research is inconclusive, lavender is often used for aromatherapy and calming lotions, while tea tree oil is promoted for acne, nail fungus, and other skin conditions

...continue reading "Avoid Lavender and Tea Tree Oils In Personal Care Products?"

Studies are accumulating evidence that the hormone disrupting effects of compounds BPA (bisphenol A) and BPS (the common substitute for BPA) have numerous negative health effects in humans, including reproductive disorders. But now a second BPA substitute - BPSIP - is also being found in humans, and may be even more persistent than BPA and BPS. This is because they're all chemically similar, and all three are endocrine disruptors. This article points out that they have slightly different effects, and when we are exposed to more than one of them (which we are), then the health effects will be even more worrisome.

Unfortunately these plasticizers are in products all around us, and so detected within almost all of us. They're in food packaging containers (and therefore in food), water bottles, can linings, toys, personal care products, thermal paper products such as cash receipts, etc. Canned foods are considered one of the most significant routes of human exposure to bisphenol A (BPA).

Other endocrine disruptors include phthalates - so read personal care product labels to avoid these. Another way to lower exposure to endocrine disruptors is to buy and store food not in plastic containers, but in glass containers or stainless steel. Don't microwave food in any sort of plastic containers. Avoid products with fragrances in them, including air fresheners. Avoid flexible vinyl (e.g. shower curtains). (For all posts on endocrine disruptors, and an article from National Institutes of Health.) From a research article by Liza Gross in PLOS Biology:

Wreaking Reproductive Havoc One Chemical at a Time

Bisphenol A (BPA), unlike DES, remained obscure until the 1950s, when chemists tapped it to make polycarbonate plastics and epoxy resins. BPA now tops the list of high-volume chemicals, and is found in numerous consumer products, including water bottles, food packaging containers and can linings, and thermal paper products like cash receipts and boarding passes (Fig 1). And because it can leach out of products, it’s been detected in the urine of nearly every person tested. It’s also been found in breast milk, follicular and amniotic fluid, cord blood, placental tissue, fetal livers, and the blood of pregnant women ...continue reading "Endocrine Disruptors BPA, BPS, and Now BPSIP"

Two recent articles about BPA (bisphenol A), BPS (bisphenol B), and the "BPA-free" label  - one a study, and one a review article. The "BPA-free" label unfortunately means the product contains a product similar to BPA (typically BPS) and with the same problems as BPA. Both articles discuss the accumulating health reasons to try to avoid these endocrine disruptors. Which is really , really tough to do given that plastics are all around us and used by us every day.

From Science Daily: Prenatal BPA exposure linked to anxiety and depression in boys

Boys exposed prenatally to a common chemical used in plastics may be morelikely to develop symptoms of anxiety and depression at age 10-12. The new study by researchers at the Columbia Center for Children's Environmental Health (CCCEH) within the Mailman School of Public Health examined early life exposure to the chemical Bisphenol A (BPA). Results are published in the journal Environmental Research.

BPA is a component of some plastics and is found in food containers, plastic water bottles, dental sealants, and thermal receipt paper. In the body, BPA is a synthetic estrogen, one of the class of chemicals known as "endocrine disruptors." The Columbia researchers, led by Frederica Perera, PhD, DrPH, director of CCCEH, previously reported that prenatal exposure to BPA was associated with emotionally reactive and aggressive behavior, and more symptoms of anxiety and depression in boys at age 7-9.

Perera and her co-investigators followed 241 nonsmoking pregnant women and their children, a subset of CCCEH's longstanding urban birth cohort study in New York City, from pregnancy through childhood....Researchers controlled for factors that have been previously associated with BPA exposure levels, including socioeconomic factors. After separating the data by sex, they found that boys with the highest levels of prenatal exposure to BPA had more symptoms of depression and anxiety than boys with lower levels of prenatal exposure to BPA; no such associations were found in girls.

From Endocrine News: Warning Signs: How Safe Is “BPA Free?”

While stickers are showing up declaring certain products “BPA Free,” that doesn’t mean they’re necessarily safe. Could bisphenol S be even worse than the compound it is supposed to be replacing? 

Human exposure to BPA is as ubiquitous as the stickers showing up now that proclaim products BPA free. The chemical used to make plastic has been linked to all kinds of reproductive issues, and even thought to play a role in the development of obesity and cardiovascular events, so industry is taking some steps to correct the problem (after much wailing and gnashing of teeth on their part). These stickers read “BPA FREE” and “NON-TOXIC PLASTIC” in bold letters and usually feature leaves and a green motif, the implication being that these products are safe and healthy. 

But “BPA free” does not mean “EDC free” [endocrine disruptor free] and many products now contain bisphenol S as a substitute for BPA. BPS is a similar chemical and has been found in everything from canned soft drinks to receipt paper to baby bottles. (The FDA banned BPA in baby bottles.) It’s been found in indoor dust samples and is beginning to show up in human urine, and it has been reported to be less biodegradable than BPA. Animal studies have implicated BPS in impaired offspring development. And the production of BPS is increasing annually.

“Recent studies testing BPS and comparing it to BPA show that BPS is as bad, if not worse, than BPA as an EDC,” says Andrea Gore, PhD, professor and Vacek Chair of Pharmacology at the University of Texas in Austin, and editor-in-chief of Endocrinology. “’BPA free’ can give consumers a false sense of security about the product.”

According to Kimberly H. Cox, a postdoctoral fellow studying reproductive endocrinology at Massachusetts General Hospital in Boston, the effects of BPA and BPS are subtler than say, PCBs or pesticides, where exposures came at high levels, with devastating effects. The effects of BPA and BPS depend on the timing, length, and dose of exposure, and numerous studies have shown that there are effects on the reproductive system, for example, at doses of BPA much lower than what has been determined as a “safe” exposure by the EPA. And now there also seem to be effects of BPS on the development of the reproductive system, as well as the brain regions that control reproduction.

“When endocrinologists talk about BPA, they frequently describe it as estrogenic – and do not point out the other endocrine systems that are being altered, such as thyroid hormone,” Wayne says. “Our paper emphasizes that BPA and BPS are activating both estrogenic and thyroid hormone pathways. This suggests that EDCs are having much broader effects on health and disease than just mimicking estrogens (which is bad enough).”

Take note: what is happening to dogs is also happening to men. Specifically, for many decades - year by year - there has been a decrease in male dog fertility. And yes, this is also happening with human male fertility - a decline in male semen quality (including sperm), along with an increase in the incidence of testicular cancer, the birth defect hypospadias, and undescended testes. This cluster of problems is called testicular dysgenesis syndrome (TGS), and it has an negative impact on male fertility.

Dr Richard Lea, who led the research said: "This is the first time that such a decline in male fertility has been reported in the dog and we believe this is due to environmental contaminants..." and "While further research is needed to conclusively demonstrate a link, the dog may indeed be a sentinel for humans -- it shares the same environment, exhibits the same range of diseases, many with the same frequency, and responds in a similar way to therapies."

What chemicals were detected that affect male fertilty? Why, the same chemicals that appear again and again in studies and are linked to a number of health problems: endocrine disruptors. Yes, they are all around us - in our food, our homes, our everyday products, our environment. From Science Daily:

Study demonstrates rapid decline in male dog fertility, with potential link to environmental contaminants

A study led by researchers at The University of Nottingham has discovered that the fertility of dogs may have suffered a sharp decline over the past three decades. The research, published in the academic journal Scientific Reports, found that sperm quality in a population of stud dogs studied over  a 26-year period had fallen significantly.The work has highlighted a potential link to environmental contaminants, after they were able to demonstrate that chemicals found in the sperm and testes of adult dogs -- and in some commercially available pet foods -- had a detrimental effect on sperm function at the concentrations detected.

 The study centered on samples taken from stud dogs at an assistance dogs breeding center over the course of 26 years. Professor Gary England.... said: "The strength of the study is that all samples were processed and analysed by the same laboratory using the same protocols during that time and consequently the data generated is robust." The work centred on five specific breeds of dogs -- Labrador retriever, golden retriever, curly coat retriever, border collie and German shepherd -- with between 42 and 97 dogs studied every year. Semen was collected from the dogs and analysed to assess the percentage of sperm that showed a normal forward progressive pattern of motility and that appeared normal under a microscope (morphology).

Over the 26 years of the study, they found a striking decrease in the percentage of normal motile sperm. Between 1988 and 1998, sperm motility declined by 2.5 per cent per year and following a short period when stud dogs of compromised fertility were retired from the study, sperm motility from 2002 to 2014 continued to decline at a rate of 1.2% per year. In addition, the team discovered that the male pups generated from the stud dogs with declining semen quality, had an increased incidence of cryptorchidism, a condition in which the testes of pups fail to correctly descend into the scrotum.

Sperm collected from the same breeding population of dogs, and testes recovered from dogs undergoing routine castration, were found to contain environmental contaminants at concentrations able to disrupt sperm motility and viability when testedThe same chemicals that disrupted sperm quality, were also discovered in a range of commercially available dog foods -- including brands specifically marketed for puppies. Dr Lea added: "We looked at other factors which may also play a part, for example, some genetic conditions do have an impact on fertility. However, we discounted that because 26 years is simply too rapid a decline to be associated with a genetic problem."

Over the past 70 years, studies have suggested a significant decline in human semen quality and a cluster of issues called 'testicular dysgenesis syndrome' that impact on male fertility which also include increased incidence of testicular cancer, the birth defect hypospadias and undescended testes.

However, declining human semen quality remains a controversial issue -- many have criticised the variability of the data of the studies on the basis of changes in laboratory methods, training of laboratory personnel and improved quality control over the years. Dr Lea added: "The Nottingham study presents a unique set of reliable data from a controlled population which is free from these factors. This raises the tantalising prospect that the decline in canine semen quality has an environmental cause and begs the question whether a similar effect could also be observed in human male fertility."

Excerpts from the original study in Scientific Reports: Environmental chemicals impact dog semen quality in vitro and may be associated with a temporal decline in sperm motility and increased cryptorchidism

A significant decline in human semen quality over the last 70 years has been widely reported1,2. The first meta-analysis reporting this phenomenon included 61 studies selected over a 50 year period (1938–1991)1 and such a trend was confirmed by re-analysis with an additional 47 studies included2.....Nevertheless, reports of declining sperm counts linked with epidemiological data on increased incidences of testicular cancer and genital tract abnormalities, is indicative of an adverse environmental effect on male reproduction6,7,8. Since these reproductive problems, termed by some as “testicular dysgenesis syndrome” (TDS), cluster in geographical areas9 they are thought to have a common aetiology and have been associated with endocrine perturbations in early life10. Exposure of developing males to environmental chemicals, particularly those with endocrine disrupting activity, is thought to be the initiator11. Although periods of development particularly sensitive to exposure encompass both pre-natal and pre-pubertal periods, environmental chemicals also perturb adult testis function e.g. gene expression and meiosis12

As ‘man’s best friend’ and closest animal companion, the dog shares the same environment, exhibits the same range of diseases, many with the same frequency, and responds in a similar way to therapeutic treatments. There is evidence that over the last 40 years, the incidence rate of canine testicular cancer has increased in parallel with changes seen in humans17,18. In addition, histological signs which characterise human TDS have recently been described in the dog19. These include seminiferous tubule abnormalities and testicular germ cell neoplasia in situ (GCNIS) cells which are known precursors of seminomas in the human20. Since human TDS includes a reduction in sperm count21 and an increased incidence of cryptorchidism, we hypothesised that the dog may exhibit similar manifestations of TDS and that this may be associated with exposure to endocrine disrupting chemicals.  

The dog is probably man’s closest companion and by sharing the same habitat, is likely to be exposed to similar environmental conditions including environmental chemicals. This was especially true in the current study since the dogs lived in homes with their handlers. Twelve chemicals detected in adult dog testes (DEHP, 7 PCB congeners, 4 PBDE congeners) were also detected in the 15 commercially available dog foods analysed