Skip to content

Researchers found that many common chemicals, including Triclosan, interfere with normal sperm function. Perhaps this is contributing to fertility problems.From Science Daily:

Endocrine disruptors impair human sperm function, research finds

A plethora of endocrine-disrupting chemicals interfere with human sperm function in a way that may have a negative impact on fertilization. These are the findings of a German -- Danish team of researchers from the Center of Advanced European Studies and Research in Bonn, Germany, and the University Department of Growth and Reproduction, Rigshospitalet, Copenhagen, Denmark. The work, which is published in EMBO reports,suggests that endocrine disruptors may contribute to widespread fertility problems in the Western world in a way that hitherto has not been recognized.

Endocrine disruptors are present in food, textiles, drugs, household, and personal-care products such as plastic bottles, toys, and cosmetics. Proving the deleterious effects of endocrine disruptors on human beings has been difficult due to a lack of suitable experimental systems.

"For the first time, we have shown a direct link between exposure to endocrine disrupting chemicals from industrial products and adverse effects on human sperm function,'' said Niels E. Skakkebaek, professor and leader of the Danish team.

Hundreds to thousands of chemicals can be rapidly tested for their potential to interfere with human sperm function using the bioassay developed by the researchers. In this initial study, about one hundred chemicals were tested. Around one third, including ultraviolet (UV) filters like 4-methylbenzylidene camphor (4-MBC) used in some sunscreens, the anti-bacterial agent Triclosan used in toothpaste, and di-n-butylphthalate (DnBP), showed adverse actions.

Altogether, the study indicates that endocrine disruptors might disturb the precisely coordinated sequence of events underlying fertilization in several ways: the chemicals might evoke changes in swimming behaviour at the wrong time and wrong place, hinder navigation of sperm towards the egg, and hamper penetration into the protective egg coat.

Different article about the same research, and here they also discuss the very important finding that mixtures of common chemicals have an even stronger adverse "cocktail effect" on sperm. From The Independent:

Chemicals in soap can cause male infertility, claim scientists

They also found that the concentrations needed to trigger these adverse reactions were similar to the very low levels commonly found within the human body. In addition, they showed for the first time that there was a “cocktail effect”, when a number of chemicals worked together to amplify their individual effects.

This study suggests another reason to avoid Triclosan. From Science Daily:

In lab tests, the antimicrobial ingredient triclosan spurs growth of breast cancer cells

Some manufacturers are turning away from using triclosan as an antimicrobial ingredient in soaps, toothpastes and other products over health concerns. And now scientists are reporting new evidence that appears to support these worries. Their study, published in the ACS journal Chemical Research in Toxicology, found that triclosan, as well as another commercial substance called octylphenol, promoted the growth of human breast cancer cells in lab dishes and breast cancer tumors in mice.

Kyung-Chul Choi and colleagues note that hormonal imbalances seem to play a role in the development of breast cancer. Given that link, researchers are investigating whether endocrine-disrupting chemicals (EDCs), which are compounds that act like hormones, might spur cancer cell growth. EDCs have become ubiquitous in products, in the environment and even in our bodies. Research has found that two EDCs -- triclosan, an antimicrobial ingredient in many products, including soaps, cosmetics and cutting boards; and octylphenol, which is in some paints, pesticides and plastics -- have accumulated in the environment. Additionally, triclosan is reportedly in the urine of an estimated 75 percent of Americans. Choi's team wanted to see what effect the two compounds have on breast cancer cells.

In tests on human breast cancer cells and in special immunodeficient mice with tissue grafts, the scientists found that both agents interfered with genes involved with breast cancer cell growth, resulting in more cancer cells. Mice that were exposed to the two compounds had larger and denser breast cancer tumors than the control group. "Although the doses of EDCs were somewhat high, we did this to simulate their effects of daily exposure, as well as body accumulation due to long-term exposure, simultaneously in animal experiments," said Choi. "Thus, exposure to EDCs may significantly increase the risk of breast cancer development and adversely affect human health," the researchers state in the paper.

The controversy over the safety of BPA (bisphenol A) is still dragging on. However, the new alternatives to BPA may not be any better and may be even worse. To minimize exposure to BPA and other estrogenic chemicals, try to buy and store food in glass bottles, jars, and containers (glass does not contain plastics of any sort). The following two articles discuss this issue. From Nature:

Toxicology: The plastics puzzle

A stroll down the aisles of a US supermarket reveals a modest victory for consumer activism. In the baby-products section, plastic baby bottles, spill-proof cups and miniature cutlery are proudly marked 'BPA-free' — a sign that they no longer contain the compound bisphenol A, found in many plastics.

The partial withdrawal of BPA is the culmination of two decades of research and hundreds of studies linking the compound — which mimics sex hormones called oestrogens — to adverse health effects in rodents and humans.  The decision by regulators in the United States and European Union to ban BPA from baby bottles, combined with industry marketing campaigns, has convinced many consumers that the plastics and other containers currently used to store food are safe.

It is a false sense of security. BPA is still a constituent of many food containers, especially cans. And when companies did abandon BPA, they often adopted compounds — such as the increasingly common bisphenol S (BPS) — that share much of the same chemistry and raise many of the same concerns as BPA. “People use this chemical to replace BPA without sufficient toxicological information,” says Kyungho Choi, an environmental toxicologist at Seoul National University. “That is a problem.”

BPA has formed the chemical backbone of most hard, clear polycarbonate plastic since the 1950s. Over time, studies have linked the chemical — which can leach out of plastics and into food — to a host of adverse health effects, including reductions in fertility and birth weight, male genital abnormalities, altered behavioural development, diabetes, heart disease and obesity1 (see Nature46411221124; 2010).

A few years ago, mounting evidence and concerned consumers convinced governments to take action. In 2011, the European Union banned BPA from baby bottles; the United States followed suit a year later. But BPA-based linings are still slathered on the insides of most food and beverage cans, and used to coat water-supply pipes in many countries. The compound is also found in dental sealants and in incubators for premature infants.

BPA-based epoxy linings are widely used because they are strong, flexible and cheap. They tolerate the high temperatures needed to sterilize foods during canning, and do not interact with a huge array of foods and beverages, according to the North American Metal Packaging Alliance in Washington DC. The alliance estimates that 95% of all aluminium and steel can coatings are epoxy-type resins: more than 99.9% of these contain BPA.

New options are beginning to surface. BPS was first made in 1869 as a dye. But because it was introduced into consumer goods only recently — into cash-register receipts in 2006, for example — few researchers have studied its toxicity. “The main question, to which we have no answer, is: 'is BPS as toxic as BPA?'” says René Habert, an endocrinologist at Paris Diderot University.

The similarity of BPS's structure to that of BPA is enough to raise suspicions that it may mimic oestrogens, says Cheryl Watson, a biochemist at the University of Texas Medical Branch in Galveston. When combined with levels of oestradiol found in adult women, BPS seemed to over-stimulate the pathway, shutting it down and causing cell suicide. The results, says Watson, were typical of those expected of an oestrogen mimic: inappropriate activation of oestrogen responses, disruption of normal oestrogen-response pathways, and eventual cell death. 

Some manufacturers have left the bisphenol family in search of a replacement. In 2007, the Eastman Chemical Company launched Tritan — a new heat-resistant clear plastic — for infant-care products such as baby bottles. This BPA-free plastic has since replaced the old BPA-containing polycarbonate in many water bottles, food containers and children's cups. 

In 2011, George Bittner, a neurobiologist at the University of Texas at Austin and the chief executive of Austin-based chemical-testing company CertiChem, reported that 92% of 102 commercially available plastic products leached chemicals with oestrogenic activity7. This included plastics advertised as BPA-free. The reason, Bittner says, is that additives in plastics — such as stabilizers and lubricants — can also bind to oestrogen receptors, as can some of the plastic monomers themselves. Tritan resins produced by Eastman were among the polymers that showed oestrogenic activity in Bittner's assays. 

In 2012, the world produced some 280 million tonnes of plastic. According to a model based on the United Nations' Globally Harmonized System of Classification and Labelling of Chemicals, more than 50% of these plastics contain ingredients that can be hazardous (see Nature 494169171; 2013). Some are carcinogenic; others are oestrogenic.

It is not yet clear how many of these chemicals are dangerous at the concentrations found in the plastics. But mixed together, the chemicals could have synergistic effects

Ideally, says Watson, the next generation of chemicals would be tested for effects on oestrogen signalling before widespread deployment in food containers.

From Mother Jones:

The Scary New Evidence on BPA-Free Plastics

BPA is in many consumer products, but research is finding more and more problems with it. The findings of these two studies may motivate people to try to lower their exposure to plastics and BPA. From Newsweek:

BPA Levels Higher in Men With Prostate Cancer: Study

Bisphenol-A is everywhere. If you are reading this in the United States, there is a greater-than-90 percent chance you have BPA in your system, according to the Centers for Disease Control. The chemical is nearly ubiquitous: it is all over your receipts and soup cans, and it gives plastic bottles useful properties like flexibility and durability. It also mimics human estrogen in the body, and studies have linked it to breast cancer, diabetes, obesity, and hormone abnormalities in children, though what doses are dangerous is a matter of debate.

Now, for the first time, scientists are adding prostate cancer to the list of possible health problems from exposure.

Prostate cancer is the second most prevalent form of cancer among men, afflicting one in six, mostly later in life. A new study published Monday in the journal Plos One found that men with prostate cancer have BPA in their urine at levels 2- to 4-fold higher than cancer-free men. Aging is the best-known risk for prostate cancer, which makes the study’s findings particularly salient: BPA concentrations were especially high in prostate cancer patients under the age of 40, when aging is less of a contributing factor to the development of prostate cancer.

From Science Daily:

BPA linked to breast cancer tumor growth

UT Arlington biochemists say their newly published study brings researchers a step closer to understanding how the commonly used synthetic compound bisphenol-A, or BPA, may promote breast cancer growth.

Subhrangsu Mandal, associate professor of chemistry/biochemistry, and Arunoday Bhan, a PhD student in Mandal's lab, looked at a molecule called RNA HOTAIR. HOTAIR is an abbreviation for long, non-coding RNA, a part of DNA in humans and other vertebrates. HOTAIR does not produce a protein on its own but, when it is being expressed or functioning, it can suppress genes that would normally slow tumor growth or cause cancer cell death.

High levels of HOTAIR expression have been linked to breast tumors, pancreatic and colorectal cancers, sarcoma and others.

UT Arlington researchers found that when breast cancer and mammary gland cells were exposed to BPA in lab tests, the BPA worked together with naturally present molecules, including estrogen, to create abnormal amounts of HOTAIR expression. 

"We were surprised to find that BPA not only increased HOTAIR in tumor cells but also in normal breast tissue," said Bhan. He said further research is needed, but the results beg the question -- are BPA and HOTAIR involved in tumor genesis in addition to tumor growth?

BPA has been widely used in plastics, such as food storage containers, the lining of canned goods and, until recently, baby bottles. It belongs to a class of endocrine disrupting chemicals, or EDCs, which have been shown to mimic natural hormones. These endocrine disruptors interfere with hormone regulation and proper function of human cells, glands and tissue. 

Acetaminophen was the one nonprescription medication that for decades pregnant women thought was safe to take. Looks like not any more - a study found that taking acetaminophen during pregnancy was associated with hyperkinetic disorder and ADHD at age 7. And the longer it was taken during pregnancy, the stronger the association. From Science Daily:

Use of acetaminophen during pregnancy linked to ADHD in children, researchers say

Acetaminophen, found in over-the-counter products such as Excedrin and Tylenol, provides many people with relief from headaches and sore muscles. When used appropriately, it is considered mostly harmless. Over recent decades, the drug, which has been marketed since the 1950s, has become the medication most commonly used by pregnant women for fevers and pain.

In a report in the current online edition of JAMA Pediatrics,researchers from the UCLA Fielding School of Public Health show that taking acetaminophen during pregnancy is associated with a higher risk in children of attention-deficity/hyperactivity disorder and hyperkinetic disorder. The data raises the question of whether the drug should be considered safe for use by pregnant women.

ADHD, one of the most common neurobehavioral disorders worldwide, is characterized by inattention, hyperactivity, increased impulsivity, and motivational and emotional dysregulation. Hyperkinetic disorder is a particularly severe form of ADHD.

The UCLA researchers used the Danish National Birth Cohort, a nationwide study of pregnancies and children, to examine pregnancy complications and diseases in offspring as a function of factors operating in early life. The cohort focuses especially on the side effects of medications and infections. The researchers studied 64,322 children and mothers who were enrolled in the Danish cohort from 1996 to 2002. 

More than half of all the mothers reported using acetaminophen while pregnant. The researchers found that children whose mothers used acetaminophen during pregnancy were at a 13 percent to 37 percent higher risk of later receiving a hospital diagnosis of hyperkinetic disorder, being treated with ADHD medications or having ADHD-like behaviors at age 7. The longer acetaminophen was taken -- that is, into the second and third trimesters -- the stronger the associations. The risks for hyperkinetic disorder/ADHD in children were elevated 50 percent or more when the mothers had used the common painkiller for more than 20 weeks in pregnancy.

"It's known from animal data that acetaminophen is a hormone disruptor, and abnormal hormonal exposures in pregnancy may influence fetal brain development," Ritz said. Acetaminophen can cross the placental barrier, Ritz noted, and it is plausible that acetaminophen may interrupt fetal brain development by interfering with maternal hormones or through neurotoxicity, such as the induction of oxidative stress, which can cause the death of neurons.

Children's brain development being harmed by chemicals in the environment - both before birth and in childhood -  is such an important topic that here are excerpts from two articles about the same report that was just released (in Lancet Neurology).  From Time:

Children Exposed to More Brain-Harming Chemicals Than Ever Before

In recent years, the prevalence of developmental disorders such as autism, attention deficit/hyperactivity disorder (ADHD) and dyslexia  have soared. While greater awareness and more sophisticated diagnoses are partly responsible for the rise, researchers say the changing environment in which youngsters grow up may also be playing a role.

In 2006, scientists from the Harvard School of Public Health and the Icahn School of Medicine at Mount Sinai identified five industrial chemicals responsible for causing harm to the brain — lead, methylmercury, polychlorinated biphenyls (found in electric transformers, motors and capacitors), arsenic (found in soil and water as well as in wood preservatives and pesticides) and toluene (used in processing gasoline as well as in paint thinner, fingernail polish and leather tanning). Exposure to these neurotoxins was associated with changes in neuron development in the fetus as well as among infants, and with lower school performance, delinquent behavior, neurological abnormalities and reduced IQ in school-age children.

Now the same researchers have reviewed the literature and found six additional industrial chemicals that can hamper normal brain development. These are manganese, fluoride, chlorpyrifos, dichlorodiphenyltrichloroethane, tetrachloroethylene and polybrominated diphenyl ethers. Manganese, they say, is found in drinking water and can contribute to lower math scores and heightened hyperactivity, while exposure to high levels of fluoride from drinking water can contribute to a seven-point drop in IQ on average. The remaining chemicals, which are found in solvents and pesticides, have been linked to deficits in social development and increased aggressive behaviors.

But they say the growing body of research that is finding links between higher levels of these chemicals in expectant mothers’ blood and urine and brain disorders in their children should raise alarms about how damaging these chemicals can be. The developing brain in particular, they say, is vulnerable to the effects of these chemicals, and in many cases, the changes they trigger are permanent. The consequence of such brain damage is impaired [central nervous system] function that lasts a lifetime and might result in reduced intelligence, as expressed in terms of lost IQ points, or disruption in behavior,” they write in their report, which was published in the journal Lancet Neurology.

Same report, from Science Daily: Growing number of chemicals linked with brain disorders in children

"The greatest concern is the large numbers of children who are affected by toxic damage to brain development in the absence of a formal diagnosis. They suffer reduced attention span, delayed development, and poor school performance. Industrial chemicals are now emerging as likely causes," said Philippe Grandjean, adjunct professor of environmental health at HSPH.

The study outlines possible links between these newly recognized neurotoxicants and negative health effects on children, including:  - Manganese is associated with diminished intellectual function and impaired motor skills  - Solvents are linked to hyperactivity and aggressive behavior - Certain types of pesticides may cause cognitive delays.

Grandjean and co-author Philip Landrigan, Dean for Global Health at Mount Sinai, also forecast that many more chemicals than the known dozen or so identified as neurotoxicants contribute to a "silent pandemic" of neurobehavioral deficits that is eroding intelligence, disrupting behaviors, and damaging societies. But controlling this pandemic is difficult because of a scarcity of data to guide prevention and the huge amount of proof needed for government regulation. "Very few chemicals have been regulated as a result of developmental neurotoxicity," they write.

The authors say it's crucial to control the use of these chemicals to protect children's brain development worldwide. They propose mandatory testing of industrial chemicals and the formation of a new international clearinghouse to evaluate industrial chemicals for potential developmental neurotoxicity.

Take note: all of us are exposed to these contaminants because they are in our environment.  The Inuit exposure is just more concentrated. From Feb. 7, 2014 Environmental Health News:

Contaminants have variety of effects on Arctic baby IQs

Babies in Arctic Canada are at risk of specific effects on their mental abilities, depending on which contaminants they are exposed to in the womb, according to a new study.While lead, methylmercury and polychlorinated biphenyls (PCBs) all are linked to neurological effects, each seems to have a different effect on infants, the scientists concluded. For example, PCBs seemed to impair the babies’ ability to recognize things they have seen.

The study involved 94 Inuit infants and their mothers from Nunavik, in northern Quebec. PCBs, mercury and other pollutants hitchhike north via prevailing winds and currents from industrialized areas, and then accumulate in food webs, predominantly in the eastern Arctic. Because the Inuit in Canada and Greenland eat top predators such as beluga whales and seals, they are among the world’s most contaminated human beings. The scientists measured the babies’ prenatal exposure to the three contaminants by testing cord blood, and then administered standard mental development tests at 6.5 months and 11 months. 

“Each contaminant was independently associated with impairment of distinct aspects of cognitive function with long-term implications for cognitive development PCBs with visual recognition memory, methylmercury with working memory and an early precursor of executive function, lead with processing speed – deficits that can already be detected during the first year of life,” the authors wrote.

For the research, scientists at Quebec’s Centre de Recherche du CHUQ, who have been studying effects of contaminants on Inuit children for two decades, teamed up with Wayne State University scientists who conducted groundbreaking work in the Great Lakes linking PCBs to reduced IQs in the 1990s.

Starting this month, it will finally be possible to buy upholstered furniture without added toxic flame retardants. From the December 31, 2013 Scientific American:

Cancer-Linked Flame Retardants Eased Out of Furniture in 2014

From the January 4, 2014 Huffington Post:

Flame-Retardant Furniture May Leave A Toxic Legacy

California's new Technical Bulletin 117 removes a decades-old requirement that flame retardants be included in the filling of upholstered furniture. The state rule, which became the de facto standard for the rest of the nation, meant use of the chemicals flourished for years nationwide, despite mounting evidence implicating them in neurological and reproductive disorders, and cancers. For all their ills, the chemicals may not actually slow fires.

"Right now, most people have harmful flame retardants in their homes and in their bodies," said Blum, a University of California, Berkeley, chemist. "And the chemicals don't serve a benefit.

As for finding new flame retardant-free furniture, Blum recommended looking for the new "TB 117-2013" tag and asking retailers whether a specific item contains flame retardants. It may be best to wait a few more months to allow new products to arrive in stores and old stock to be sold out, she noted.