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Another article was published this month raising the issue of whether Alzheimer's disease is caused by a microbe - which can explain why all the medicines and experimental drugs aimed at treating the "tangles" or amyloid plaques in the brain are not working as a treatment (because that's the wrong approach). The microbe theory of Alzheimer's disease has been around for decades, but only recently is it starting to be taken seriously. Some of the microbes found in patients with Alzheimer's disease (from analyses of both normal brains and Alzheimer patient brains after death): fungi, Borrelia burgdorferi (Lyme disease), herpes simplex virus Type 1 (HSV1), and Chlamydia pneumoniae.

The general hypotheses seem to be that Alzheimer’s disease is caused by infection, but it isn't linked to any one pathogenic microbe.  Instead, the evidence seems to support that "following infection, certain pathogens gain access to brain, where immune responses result in the accumulation of amyloid-β, leading to plaque formation". So the microbes act as "triggers" for Alzheimer's disease - the microbes get into the brain, and immune responses somehow eventually result in the amyloid plaques and Alzheimer's disease. From The Scientist:

Do Microbes Trigger Alzheimer’s Disease?

In late 2011, Drexel University dermatology professor Herbert Allen was astounded to read a new research paper documenting the presence of long, corkscrew-shape bacteria called spirochetes in postmortem brains of patients with Alzheimer’s disease. Combing data from published reports, the International Alzheimer Research Center’s Judith Miklossy and colleagues had found evidence of spirochetes in 451 of 495 Alzheimer’s brains. In 25 percent of cases, researchers had identified the spirochete as Borrelia burgdorferi, a causative agent of Lyme disease. Control brains did not contain the spirochetes.

Allen had recently proposed a novel role for biofilms—colonies of bacteria that adhere to surfaces and are largely resistant to immune attack or antibiotics—in eczema....  Allen knew of recent work showing that Lyme spirochetes form biofilms, which led him to wonder if biofilms might also play a role in Alzheimer’s disease. When Allen stained for biofilms in brains from deceased Alzheimer’s patients, he found them in the same hippocampal locations as amyloid plaquesToll-like receptor 2 (TLR2), a key player in innate immunity, was also present in the same region of the Alzheimer’s brains but not in the controls. He hypothesizes that TLR2 is activated by the presence of bacteria, but is locked out by the biofilm and damages the surrounding tissue instead.

Spirochetes, common members of the oral microbiome, belong to a small set of microbes that cross the blood-brain barrier when they’re circulating in the blood, as they are during active Lyme infections or after oral surgery. However, the bacteria are so slow to divide that it can take decades to grow a biofilm. This time line is consistent with Alzheimer’s being a disease of old age, Allen reasons, and is corroborated by syphilis cases in which the neuroinvasive effects of spirochetes might appear as long as 50 years after primary infection.

Allen’s work contributes to the revival of a long-standing hypothesis concerning the development of Alzheimer’s. For 30 years, a handful of researchers have been pursuing the idea that pathogenic microbes may serve as triggers for the disease’s neuropathology..... In light of continued failures to develop effective drugs, some researchers, such as Harvard neurobiologist Rudolph Tanzi, think it’s high time that more effort and funding go into alternative theories of the disease. “Any hypothesis about Alzheimer’s disease must include amyloid plaques, tangles, inflammation—and, I believe, infection.”

Herpes simplex virus type 1 (HSV1) can acutely infect the brain and cause a rare but very serious encephalitis. In the late 1980s, University of Manchester molecular virologist Ruth Itzhaki noticed that the areas of the brain affected in HSV1 patients were the same as those damaged in patients with Alzheimer’s disease. Knowing that herpes can lie latent in the body for long periods of time, she began to wonder if there was a causal connection between the infection and the neurodegenerative disorder.

Around the same time, neuropathologist Miklossy, then at the University of Lausanne in Switzerland, was detailing the brain damage caused by spirochetes—both in neurosyphilis and neuroborrelia, a syndrome caused by Lyme bacteria. She happened upon a head trauma case with evidence of bacterial invasion and plaque formation, and turned her attention to Alzheimer’s. She isolated spirochetes from brain tissue in 14 Alzheimer’s patients but detected none in 13 age-matched controls. In addition, monoclonal antibodies that target the amyloid precursor protein (APP)—which, when cleaved, forms amyloid-β—cross-reacted with the spirochete species found, suggesting the bacteria might be the source of the protein.

Meanwhile, in the U.S., a third line of evidence linking Alzheimer’s to microbial infection began to emerge. While serving on a fraud investigation committee, Alan Hudson, a microbiologist then at MCP-Hahnemann School of Medicine in Philadelphia, met Brian Balin.... Soon, Balin began to send Hudson Alzheimer’s brain tissue to test for intracellular bacteria in the Chlamydia genus. Some samples tested positive for C. pneumoniae: specifically, the bacteria resided in microglia and astrocytes in regions of the brain associated with Alzheimer’s neuropathology, such as the hippocampus and other limbic system areas. Hudson had a second technician repeat the tests before he called Balin to unblind the samples. The negatives were from control brains; the positives all had advanced Alzheimer’s disease. "We were floored,” Hudson says.

Thus, as early as the 1990s, three laboratories in different countries, each studying different organisms, had each implicated human pathogens in the etiology of Alzheimer’s disease. But the suggestion that Alzheimer’s might have some microbial infection component was still well outside of the theoretical mainstream. Last year, Itzhaki, Miklossy, Hudson, and Balin, along with 29 other scientists, published a review in the Journal of Alzheimer’s Disease to lay out the evidence implicating a causal role for microbes in the disease.

The microbe theorists freely admit that their proposed microbial triggers are not the only cause of Alzheimer’s disease. In Itzhaki’s case, some 40 percent of cases are not explained by HSV1 infection. Of course, the idea that Alzheimer’s might be linked to infection isn’t limited to any one pathogen; the hypothesis is simply that, following infection, certain pathogens gain access to brain, where immune responses result in the accumulation of amyloid-β, leading to plaque formation.

Two studies looked at manganese and found that high levels are associated with problems. Manganese is an essential trace mineral necessary for development, metabolism, the antioxidant system, and for normal brain and nerve function. Getting manganese through foods (e.g. nuts, seeds, whole grains) is beneficial, but ingesting large amounts through supplements or being exposed to high levels in some other way (such as polluted air) is associated with various health problems. 

The first study found that high manganese in the diet (in mice) was associated with an increased risk of staph (Staphylococcus aureus) heart infection. The second study (done in East Liverpool, Ohio) found that exposure to consistently high levels of manganese in the air is associated with lower IQ scores in children. And why did the air the children were breathing have high levels of manganese? Because there was a nearby hazardous waste incinerator and a facility that handles manganese.

From Medical Xpress: Excess dietary manganese promotes staph heart infection

Too much dietary manganese—an essential trace mineral found in leafy green vegetables, fruits and nuts—promotes infection of the heart by the bacterium Staphylococcus aureus ("staph"). The findings, reported this week in the journal Cell Host & Microbe, add to the evidence that diet modifies risk for infection. The discovery also suggests that people who have excess levels of tissue manganese, including those who consume dietary supplements with high concentrations of the metal, may be at increased risk for staph infection of the heart.

Skaar and his colleagues studied the impact of dietary manganese on staph infection in a mouse model. Most of the mice that consumed a high manganese diet—about three times more manganese than normal—died after infection with staph. The investigators discovered that the animals on the high manganese diet were particularly susceptible to staph infection of the heart, which was a surprise, said Skaar, who is also professor of Pathology, Microbiology and Immunology.... The researchers found that excess manganese inactivates a key line of defense against pathogens: the innate immune system's reactive oxygen burst. 

Staph is the leading cause of bacterial endocarditis (infection of the inner lining of the heart chamber and heart valves) and the second most frequent cause of bloodstream infections. Interestingly, some populations of people have both increased risk for staph infections, particularly endocarditis, and higher than normal levels of tissue manganese, Skaar noted. These populations include intravenous drug users, patients with chronic liver disease and patients on long-term intravenous diets.

From Medical Xpress: Higher manganese levels in children correlate with lower IQ scores, study finds

A study led by environmental health researchers at the University of Cincinnati (UC) College of Medicine finds that children in East Liverpool, Ohio with higher levels of Manganese (Mn) had lower IQ scoresThe study analyzed blood and hair samples of 106 children 7 to 9 years of age from East Liverpool and surrounding communities, who enrolled in the study from March 2013 to June 2014.... The study found that increased Mn in hair samples was significantly associated with declines in full-scale IQ, processing speed and working memory.

Manganese is an element generally found in combination with iron and many minerals. It plays a vital role in brain growth and development, but excessive exposure can result in neurotoxicity. Manganese is used widely in the production of steel, alloys, batteries and fertilizers and is added to unleaded gasolineLocated in northeast Ohio along the Ohio River, East Liverpool has a demonstrated history of environmental exposures, with EPA records showing elevated levels of manganese concentrations since 2000.... all  [air] monitors in East Liverpool had "consistently exceeded" health-based guidelines set by the agency.

 Manganese (Mn). Credit: Wikipedia

Image result for chlamydia wikipediaThe annual Sexually Transmitted Disease Surveillance Report was released today by the US Centers for Disease Control and Prevention (CDC) and the news wasn't good. More than two million cases of chlamydia, gonorrhea and syphilis were reported in the United States in 2016 - the highest number ever. But the CDC acknowledges that the actual numbers are far higher - that most cases of STDs are not reported to the CDC. The CDC estimates that there are actually 20 million new STDs in the U.S. each year, including other sexually transmitted diseases such as genital herpes and human papillomavirus, and half of these are among young people ages 15 to 24 years.

The report discusses the four STDs (sexually transmitted diseases) that are reported to the CDC. The 4th one is chancroid, but there were only 7 cases reported last year. Most of the new cases of STDs involved chlamydia, a bacterial infection that affects both men and women - about 1.6 million cases were reported to the CDC. Gonorrhea also increased among men and women last year, but the steepest rise was among men, especially among men who have sex with men (MSM). The CDC is especially concerned about the threat of gonorrhea becoming resistant to all treatments. Untreated STDs have serious health consequences (e.g. infertility, still-birth in infants)

This report stresses the need for STD screening and treatment, especially among pregnant women (make it part of prenatal care). There is also a need for STD education, and greater use of condoms to reduce risk of STDs. The CDC has a page on STD prevention (practice abstinence, use condoms, have fewer sexual partners and exclusive relationships, get the HPV vaccine, and talk with your partner about safe sex).  Excerpts from CDC:

STDs at record high, indicating urgent need for prevention

More than two million cases of chlamydia, gonorrhea and syphilis were reported in the United States in 2016, the highest number ever, according to the annual Sexually Transmitted Disease Surveillance Report released today by the Centers for Disease Control and Prevention (CDC).

The majority of these new diagnoses (1.6 million) were cases of chlamydia. There were also 470,000 gonorrhea cases and almost 28,000 cases of primary and secondary syphilis – the most infectious stages of the disease. While all three of these STDs can be cured with antibiotics, if left undiagnosed and untreated, they can have serious health consequences, including infertility, life-threatening ectopic pregnancy, stillbirth in infants, and increased risk for HIV transmission.

While young women continue to bear the greatest burden of chlamydia (nearly half of all diagnosed infections), surges in syphilis and gonorrhea are increasingly affecting new populations.

Syphilis rates increased by nearly 18 percent overall from 2015 to 2016. The majority of these cases occur among men – especially gay, bisexual and other men who have sex with men (MSM) – however, there was a 36 percent increase in rates of syphilis among women, and a 28 percent increase in syphilis among newborns (congenital syphilis) during this period. More than 600 cases of congenital syphilis were reported in 2016, which has resulted in more than 40 deaths and severe health complications among newborns. The disease is preventable through routine screening and timely treatment for syphilis among pregnant women.

While gonorrhea increased among men and women in 2016, the steepest increases were seen among men (22 percent). Research suggests that a large share of new gonorrhea cases are occurring among MSM. These trends are particularly alarming in light of the growing threat of drug resistance to the last remaining recommended gonorrhea treatment.

Image result for chlamydia wikipedia Chlamydia trachomatis (chlamydia) - in brown. Credit: Wikipedia

Finally - research is being done on ear microbiomes (the community of microbes that live in the ears) and how they differ in people with ear infections and those without ear infections. A recently presented ear microbiome study (at the annual American Academy of Otolaryngology meeting) makes perfect sense, and ties in perfectly with sinus microbiome research. Specifically, that there are microbial communities or microbiomes in the ears, and if the microbial communities go out of whack (dysbiosis) it can cause symptoms (ear infection).

This research reminds me of a wonderful anecdote about ear infections and how they could possibly be treated - an ear wax transplant. From a 2012 article in ENT Today: Restoring Microbial Balance Key to Keeping Sinuses Healthy

Andrew Goldberg, MD, never tires of telling people about how he was outsmarted by a patient while working as a second-year otolaryngology resident at the University of Pittsburgh. Now the director of rhinology and sinus surgery at the University of California San Francisco Medical Center, Dr. Goldberg recalled how he assisted in the examination of a patient with a history of chronic otiti sexterna [ear infection] in one ear. Despite repeated trips to doctors for antibiotics, vinegar washes and drops, the patient’s ear trouble always came back.

Not this time. The doctors assumed that their treatments had finally done the trick, only to be told by the patient that he had likely cured himself by taking earwax from his good ear and sticking it in his bad ear. “I had no idea what that meant. I’m sure that we assumed, at the time, that what he was telling us was nonsense, that he was a little nutty,” Dr. Goldberg said. “We never thought anything more about it.”

The home remedy, however, now seems prescient in light of accumulating research suggesting that microbiomes, or distinct bacterial communities that coexist with us throughout our bodies, may play key roles in maintaining human health. When he began conducting his own microbiome research about five years ago, Dr. Goldberg realized that his former patient may have taken an intact, healthy microbiome and used it to re-inoculate the disrupted bacterial community in his bad ear.

Description of the recently presented study - unfortunately no details were given about specific microbes. From Health Day News at Medline Plus: 'Microbiomes' May Hold Key to Kids' Ear Infections

Recurrent ear infections are the bane of many children -- and the parents who have to deal with their care. Now, research suggests that naturally occurring, "helpful" bacterial colonies in the ear -- called "microbiomes" by scientists -- may help decide a person's vulnerability to these infections. "The children and adults with normal middle ears differed significantly in terms of middle ear microbiomes," concluded a team of Japanese researchers led by Dr. Shujiro Minami of the National Institute of Sensory Organs in Tokyo.

These bacterial ear infections -- called otitis media -- typically start in the middle ear, and 5 out of 6 kids will develop at least one ear infection by the time they turn 3. In the new study, Minami and colleagues wanted to see what role the ear's microbiome might play in these outbreaks. To do so, they took swab samples of the middle ears of 155 children and adults who were having ear surgery due to recurrent ear infections (88 cases) or some other condition.

Among patients with a history of ear infections, the researchers found significant differences in the makeup of microbial communities for people with active ("wet") or inactive ("dry") inflammation. In fact, people whose ear infection was dormant "had similar middle ear microbiomes as the normal [no ear infection] middle ears group," the researchers said. On the other hand, the researchers found that people with an active ear infection had bacterial communities that differed widely from those of people not suffering such outbreaks.

Another problem for overweight or obese men: an increased risk of poor sperm quality. Researchers in India found that compared to normal weight men, obesity was associated with lower sperm count, lower volume of semen, lower sperm concentration, poor sperm motility (the movement of sperm), as well as sperm defects. There is some evidence (from other studies and the researchers own work) that there is improvement in sperm quality with weight loss.

The researchers pointed out that other studies have shown that "paternal obesity at conception had deleterious effects on embryo health, implantation, pregnancy, and live birth rates." And that poor sperm quality is a cause of infertility. So.... what do the researchers recommend? Weight loss and exercise, and perhaps bariatric surgery, for obese men having fertility problems due to poor sperm quality. From Medical Xpress: 

As men's weight rises, sperm health may fall

A widening waistline may make for shrinking numbers of sperm, new research suggests. Indian scientists studied more than 1,200 men and found that too much extra weight was linked to a lower volume of semen, a lower sperm count and lower sperm concentration. In addition, sperm motility (the ability to move quickly through the female reproductive tract) was poor. The sperm had other defects as well, the researchers added. Poor sperm quality can lower fertility and the chances of conception.

"It's known that obese women take longer to conceive," said lead researcher Dr. Gottumukkala Achyuta Rama Raju, from the Center for Assisted Reproduction at the Krishna IVF Clinic, in Visakhapatnam. "This study proves that obese men are also a cause for delay in conception," he added.

But in continuing research, the study team is looking to see if losing weight will improve the quality of sperm. Although that study is still in progress, early signs look good that sperm quality improves as men lose weight, Rama Raju said. Recent reports have found that extreme weight loss after bariatric surgery reversed some of the sperm decline, he said.

For the study, Rama Raju and his colleagues used computer-aided sperm analysis to assess the sperm of 1,285 men. Obese men, they found, had fewer sperm, a lower concentration of sperm and inability of the sperm to move at a normal speed, compared with the sperm of men of normal weight. Moreover, the sperm of obese men had more defects than other sperm. These defects included defects in the head of the sperm, such as thin heads and pear-shaped heads.  [Original study.]

 Human sperm. Credit: Wikipedia

This is part 2 of posts about tiny particles of plastic (microfibers) in our water - which is a form of water pollution. These plastic fibers are smaller than 5 mm, and are found in water (drinking water, rivers, oceans) throughout the world. An investigative study by Orb Media (done by research scientists) took numerous drinking water samples from more than a dozen nations and analyzed them. They found that 83% of drinking water samples worldwide, and 94% of drinking water samples taken in the US (which included tap water from Congressional buildings, the US Environmental Protection Agency’s headquarters, Trump Tower in New York, and bottled waters) contained plastic microfibers.

The last post discussed  research finding plastic microfibers in rivers, and how they are now found in fish and shellfish - and so eventually in us (we eat fish and shellfish, don't we?). The plastic microfibers are in our food chain, and there is tremendous concern over what that is doing to wildlife and to us, especially as the microfibers accumulate. Well, we also now know that the plastic microfibers are found in drinking water, are in the air, and can be found in foods tested (even beer).

So what are these plastic microfibers doing to us? And how can we reduce the number of microfibers being released into the air? The Orb Media site discusses sources of plastic microfibers in the environment (from clothes being washed, tire dust, paint dust, etc.) to how we personally can generate fewer plastic microfibers (try not to use plastic bags or straws, etc.). Excerpts from The Guardian:

Plastic fibres found in tap water around the world, study reveals

Microplastic contamination has been found in tap water in countries around the world, leading to calls from scientists for urgent research on the implications for health. Scores of tap water samples from more than a dozen nations were analysed by scientists for an investigation by Orb Media, who shared the findings with the Guardian. Overall, 83% of the samples were contaminated with plastic fibres.

The US had the highest contamination rate, at 94%, with plastic fibres found in tap water sampled at sites including Congress buildings, the US Environmental Protection Agency’s headquarters, and Trump Tower in New York. Lebanon and India had the next highest rates. European nations including the UK, Germany and France had the lowest contamination rate, but this was still 72%. The average number of fibres found in each 500ml sample ranged from 4.8 in the US to 1.9 in Europe.

The new analyses indicate the ubiquitous extent of microplastic contamination in the global environment. Previous work has been largely focused on plastic pollution in the oceans, which suggests people are eating microplastics via contaminated seafood. “We have enough data from looking at wildlife, and the impacts that it’s having on wildlife, to be concerned,” said Dr Sherri Mason, a microplastic expert at the State University of New York in Fredonia, who supervised the analyses for Orb. “If it’s impacting [wildlife], then how do we think that it’s not going to somehow impact us?”

Mahon said there were two principal concerns: very small plastic particles and the chemicals or pathogens that microplastics can harbour. “If the fibres are there, it is possible that the nanoparticles are there too that we can’t measure,” she said. “Once they are in the nanometre range they can really penetrate a cell and that means they can penetrate organs, and that would be worrying.” The Orb analyses caught particles of more than 2.5 microns in size, 2,500 times bigger than a nanometre. [NOTE: This means they were not able to test for smaller sizes.]

The scale of global microplastic contamination is only starting to become clear, with studies in Germany finding fibres and fragments in all of the 24 beer brands they tested, as well as in honey and sugar. In Paris in 2015, researchers discovered microplastic falling from the air, which they estimated deposits three to 10 tonnes of fibres on the city each year, and that it was also present in the air in people’s homes.

How microplastics end up in drinking water is for now a mystery, but the atmosphere is one obvious source, with fibres shed by the everyday wear and tear of clothes and carpets. Tumble dryers are another potential source, with almost 80% of US households having dryers that usually vent to the open air. “We really think that the lakes [and other water bodies] can be contaminated by cumulative atmospheric inputs,” said Johnny Gasperi, at the University Paris-Est Créteil, who did the Paris studies. “What we observed in Paris tends to demonstrate that a huge amount of fibres are present in atmospheric fallout.”.... Plastic fibres may also be flushed into water systems, with a recent study finding that each cycle of a washing machine could release 700,000 fibres into the environment. Rains could also sweep up microplastic pollution, which could explain why the household wells used in Indonesia were found to be contaminated. 

Microfibers found in the Hudson River. Credit: PBS News Hour, Sara Cathey, Adventure Scientists

You may not think of your clothes as pollutants, but tiny plastic fibers from synthetic textiles (microfibers) are big contributors to water pollution. Clothes and fabrics made with synthetic fibers are using plastic fibers (e.g. polyester, nylon, acrylic, fleece and athletic clothing). When they are washed, they break apart in the washing machine, and so get into the wastewater system, and eventually into our rivers and oceans.

These microplastic particles are smaller than 5 mm. One 2011 study found that "Experiments sampling wastewater from domestic washing machines demonstrated that a single garment can produce greater than 1900 fibers per wash" (which then goes directly into wastewater). And while a 2017 study didn't examine sources of microfibers (air, rain, water treatment plants, etc) found in numerous Hudson River water samples, the researchers estimate that the entire Hudson River dumps 300 million human-made fibers into the Atlantic Ocean each day. Wow.

In the past few weeks a number of articles and studies have been published about these small plastic pieces (microfibers) that are found in our water - yes, in our drinking water, as well as our rivers, seas, and oceans. Which eventually get into birds, fish and shellfish - and so eventually into us. So the microfibers are in our food chain. There is tremendous concern over what that is doing to wildlife and to us, especially as the microfibers accumulate. We all use plastics every day and most of us wear clothing made of plastic fibers (synthetic fibers), and we're not about to stop. (NOTE: No matter what fabrics we wear, our clothing also sheds fibers into the air, so we leave a trail of fibers behind us, including at crime scenes. Synthetic and natural materials - such as cotton and wool, both shed.)

The big questions: Can anything be done to stop this water pollution? And what is it doing to us and wildlife? Today I am posting links to these stories because it is of concern to all of us and to future generations, and we need to think about and address this issue.

Excerpts from PBS News Hour: This New York river dumps millions of fabric microfibers into the ocean daily

The faded, “distressed look” of a favorite pair of blue jeans, may come with a hidden price for the residents of New York. The Hudson River dumps 300 million clothing fibers into the Atlantic Ocean each day, according to a recent study in the Marine Pollution Bulletin. Many of the fibers come from aging clothes, rinsed out with the laundry and into the environment. Approximately half of the fibers were plastic, while the remainder were spun from natural materials like cotton or wool. Invisible to the naked eye, these fibers can cause health problems for animals and humans.

Barrows, who has been studying microfiber pollution in oceans for more than five years, wanted to learn more about what’s happening upstream in freshwater. So last year, Barrows and a team of scientists and volunteers measured microfiber pollution across all 13,300 miles of the Hudson river..... The team found about one microfiber per liter of water, which seems small until you consider the sheer volume of the Hudson River. An average-sized, above-ground swimming pool filled with this water would contain about 10,800 microfibers, and the entire Hudson River dumps 300 million human-made fibers into the Atlantic Ocean each day. [Original Hudson River study.]

If wastewater treatment facilities are not the major culprit, people may want to look their everyday clothes. Fabrics cast off tiny threads at every stage of their life. Even crime scene investigators count on perpetrators leaving behind bits of clothing. “We are just not conscious of it,” Carr said. “It’s invisible, but everywhere you go and everywhere I go, we are leaving a trail of fibers in our wake.”

Pollutants and other fine particles can hang in the air and travel great distances, said George Thurston, who studies the health effects of air pollution at New York School of Medicine. These airborne fibers can also be toxic. During the industrial revolution, byssinosis or brown lung disease, befell textile plant workers due to cotton or other fibers in the factory’s air. But Thurston said more research is needed to ascertain how microfibers get around.

Microfibers found in the Hudson River. Credit: PBS News Hour, Sara Cathey, Adventure Scientists



An interesting article that describes the difficulty of capturing tiny plastic microfibers at sewage and water treatment plants in Minnesota. From MPR News: Microplastics could pose big treatment challenges

So-called microplastics are tiny — less than 5 millimeters across. They can come from litter or plastic bags that break down over time. ...."These small little threads, they find their way into the wastewater treatment system and then, into our aquatic environment."

Austin Baldwin, a hydrologist with the U.S. Geological Survey, studied the St. Croix, Namekagon and Mississippi rivers in 2015. The results were published earlier this year in a brief issued by the National Park Service. Baldwin's team found microplastics in all of the samples they took of water, sediment, fish and mussels. The level of concentration was surprising: They found as many as 111 microscopic pieces of plastic in a single fish. Scientists worry that microplastics might clog the digestive systems of fish and make them feel full, so they end up starving. Baldwin said there need to be more study of the biological impacts.

Microplastic fibers in the wastewater are so small they slip through filters and screens designed to capture larger particles. Hoellin's team sampled Chicago rivers and found higher concentrations of microplastics downstream of sewer plants. "What I've seen is that some wastewater treatment plants are really effective at retaining 99 percent of the microplastic that comes in as raw sewage," Hoellin said. "But even that 1 percent, when it's added up on a daily, yearly basis, is amounting to a lot of plastic pollution." Hoellin noted there's no legal requirement for wastewater plants to treat for microplastics. "

By the time the treated wastewater is discharged into the Mississippi River, Rogacki [Larry Rogacki, assistant general manager of the Metropolitan Wastewater Treatment Plant in St. Paul, MN] estimates that 96-98 percent of all microplastics have been removed. Retrofitting the plant to eliminate 100 percent of microplastics would require installing sand filters that could capture smaller particles, he said. It would be costly — close to $1 billion. ....What scientists say might be more effective — and less expensive — is to figure out how to keep plastic out of the wastewater stream in the first place.

A number of people contacting me have indicated that living in a house or apartment with a mold problem led to their chronic sinusitis. And it wasn't the dreaded toxic black mold (varieties of mold which can cause serious neurological symptoms), but common molds that triggered their inflammatory reactions, respiratory symptoms, allergies, and eventually chronic sinusitis. All due to excessive mold exposure.

This summer's flooding caused by hurricanes and tropical storms will result in major mold growth in residences after the water recedes. What will be the health consequences? Article excerpts about mold (and with impressive photos) from The Atlantic:

The Looming Consequences of Breathing Mold

But the impact of hurricanes on health is not captured in the mortality and morbidity numbers in the days after the rain. This is typified by the inglorious problem of mold. Submerging a city means introducing a new ecosystem of fungal growth that will change the health of the population in ways we are only beginning to understand. The same infrastructure and geography that have kept this water from dissipating created a uniquely prolonged period for fungal overgrowth to take hold, which can mean health effects that will bear out over years and lifetimes.

The documented dangers of excessive mold exposure are many. Guidelines issued by the World Health Organization note that living or working amid mold is associated with respiratory symptoms, allergies, asthma, and immunological reactions. The document cites a wide array of “inflammatory and toxic responses after exposure to microorganisms isolated from damp buildings, including their spores, metabolites, and components,” as well as evidence that mold exposure can increase risks of rare conditions like hypersensitivity pneumonitis, allergic alveolitis, and chronic sinusitis.

Twelve years ago in New Orleans, Katrina similarly rendered most homes unlivable, and it created a breeding ground for mosquitoes and the diseases they carry, and caused a shortage of potable water and food. But long after these threats to human health were addressed, the mold exposure, in low-income neighborhoods in particular, continued. The same is true in parts of Brooklyn, where mold overgrowth has reportedly worsened in the years since Hurricane Sandy. In the Red Hook neighborhood, a community report last October found that a still-growing number of residents were living in moldy apartments.

The highly publicized “toxic mold”—meaning the varieties that send mycotoxins into the air, the inhaling of which can acutely sicken anyone—causes most concern right after a flood. In the wake of Hurricane Matthew in South Carolina last year, sludge stood feet deep in homes for days. As it receded, toxic black mold grew. In one small community, Nichols, it was more the mold than the water itself that left the town’s 261 homes uninhabitable for months.

The more insidious and ubiquitous molds, though, produce no acutely dangerous mycotoxins but can still trigger inflammatory reactions, allergies, and asthma. The degree of impact from these exposure in New Orleans after Hurricane Katrina is still being studied.

Molds also emit volatile chemicals that some experts believe could affect the human nervous system. Among them is Joan Bennett, a distinguished professor of plant biology and pathology at Rutgers University, who has devoted her career to the study of fungal toxins. She was living in New Orleans during the storm, and she recalls that while some health experts were worried about heavy-metal poisoning or cholera, she was worried about fungus.

The smell of the fungi in her house got so strong after the flooding that it gave her headaches and made her nauseated. As she evacuated, wearing a mask and gloves, she took samples of the mold along with her valued possessions. Her lab at Rutgers went on to report that the volatile organic compounds emitted by the mold, known as mushroom alcohol, had some bizarre effects on fruit flies. For one, they affected genes involved in handling and transporting dopamine in a way that mimicked the pathology of Parkinson’s disease in humans. “More biologists ought to be looking at gas-phase compounds, because I’m quite certain we’ll find a lot of unexpected effects that we’ve been ignoring,” said Bennett.

 Mold in ceiling.  Credit: CDC

Tattoos are very popular these days, with about 29% of Americans having one or more. But there also is concern because so little is known about tattoo inks and any health effects on the body, and because adverse effects (e.g. inflammatory reactions) can occur months or years later. One study of 300 people in New York City with tattoos found that 10.3% reported experiencing an adverse tattoo reaction, of which 6% reported suffering from a chronic reaction from a specific color (especially red and black ink) that lasted for more than 4 months.

Now a new study in the journal Scientific Reports reports that microscopic particles from tattoo inks can migrate into the body and wind up in the lymph nodes of the immune system. Most tattoo inks contain particles of varying sizes - with some being very small nanoparticles. The researchers analyzed the skin and lymph nodes of 4 tattooed corpses and 2 corpses with no tattoos. They found the presence of several toxic elements such as nickel, chromium, cadmium, aluminum from the colorful tattoo inks. They found tattoo pigment particles in the skin, and that smaller ink nanoparticles had traveled to the lymph nodes - which leads to chronic enlargement of those lymph nodes, as well as lifelong exposure. From Science Daily:

Nanoparticles from tattoos travel inside the body, scientists find

The elements that make up the ink in tattoos travel inside the body in micro and nanoparticle forms and reach the lymph nodes according to a study published in Scientific Reports on 12 September by scientists from Germany and the ESRF, the European Synchrotron, Grenoble (France). 

The reality is that little is known about the potential impurities in the colour mixture applied to the skin. Most tattoo inks contain organic pigments, but also include preservatives and contaminants like nickel, chromium, manganese or cobalt. Besides carbon black, the second most common ingredient used in tattoo inks is titanium dioxide (TiO2), a white pigment usually applied to create certain shades when mixed with colorants. TiO2 is also commonly used in food additives, sun screens, paints. Delayed healing, along with skin elevation and itching, are often associated with white tattoos, and by consequence with the use of TiO2. 

"We already knew that pigments from tattoos would travel to the lymph nodes because of visual evidence: the lymph nodes become tinted with the colour of the tattoo. It is the response of the body to clean the site of entrance of the tattoo. What we didn't know is that they do it in a nano form, which implies that they may not have the same behaviour as the particles at a micro level. And that is the problem: we don't know how nanoparticles react," explains Bernhard Hesse, one of the two first authors of the study and ESRF visiting scientist.

X-ray fluorescence measurements on ID21 allowed the team to locate titanium dioxide at the micro and nano range in the skin and the lymphatic environment. They found a broad range of particles with up to several micrometres in size in human skin but only smaller (nano) particles transported to the lymph nodes. This may lead to the chronic enlargement of the lymph node and lifelong exposure [Original study.]

An opinion piece in a journal raises the question of whether having some parasites in the gut is beneficial. We tend to think of parasites as harmful (and yes, some parasite species cause tremendous human suffering and death), but some others seem to exist harmlessly in humans. I'm posting this article because the authors raise the question of whether with progress (sanitation, antibiotics, a Western diet, etc.) we have also lost something beneficial to humans - one-celled organisms (protozoa) that are parasites. They are found in people living in undeveloped countries, but people in developed countries have usually few or none.

Which leads to the question - is the loss of these parasites one of the reasons for the major increase in autoimmune disorders and such diseases as Crohn's disease and colitis? The answers to these questions are unknown at this time, so studies are needed. The authors point out that after millions of years of coevolution, the protists could be providing some beneficial effects to their human hosts - and that they may be part of a normal, healthy gut microbial community (microbiome).

As we know, studies show that in developed Western countries (as compared to undeveloped countries) there is lower microbial diversity in the gut - in other words, with industrialization comes lower bacterial diversity. But... higher microbial diversity is considered beneficial. Normally the human gut has hundreds of microbial species (bacteria, viruses, fungi) living in it and interacting. Some diseases or conditions result in alterations in these microbes, and even "microbial communities being out of whack" (dysbiosis).  The authors of the paper give examples of how the presence of certain non-pathogenic protozoan species in the gut is linked to higher gut microbial diversity and with the presence of bacteria that are anti-inflammatory and beneficial.

KEEP IN MIND: Gut protozoa are one-celled organisms (called protists) that live in the gut as parasites. Numerous protozoa can inhabit the gastrointestinal tract of humans.  According to a Tulane Univ. site "The majority of these protozoa are non-pathogenic commensals, or only result in mild disease", but some of these organisms can cause severe disease under certain conditions. [NOTE: commensal = characterized by a relationship in which one species is benefited while the other is unaffected]. In the following excerpts, a helminth refers to a parasitic worm, such as a fluke, tapeworm, or nematode.

Excerpts from Trends in Parasitology:  Gut Protozoa: Friends or Foes of the Human Gut Microbiota?

The importance of the gut microbiota for human health has sparked a strong interest in the study of the factors that shape its composition and diversity.... We argue that protozoa, like helminths, represent an important factor to take into account when studying the gut microbiome, and that their presence – especially considering their long coevolutionary history with humans – may be beneficial. From this perspective, we examine the relationship between the protozoa and their hosts, as well as their relevance for public health.

The human gut microbiota spans the tree of life and includes bacteria, viruses, and eukaryotes such as fungi, helminths, and protozoa. ...The observation that the gut bacterial microbiome is less diverse in populations from industrialized countries, compared to nonindustrialized countries, has been mostly explained by differences in dietary fiber intake, food sterilization, and the use of antibiotics. Here, we propose that the decreased prevalence of helminths and gut protozoa in industrialized countries is partly responsible for this loss of bacterial diversity.

We argue, based on the knowledge of helminths, that some intestinal protozoa might have beneficial effects on their host through their influence on the gut bacterial microbiome. The role of protozoa in shaping the gut microbiome of healthy individuals remains, however, largely unrecognized. The mechanisms through which protozoa influence the gut bacteria – and the consequences for human health of their absence in developed countries – are poorly understood and call for further attention. 

 The question is therefore whether gut eukaryotes are simply parasites that are detrimental to human health or whether, on the contrary, they could provide, after millions of years of coevolution, some beneficial effects to their hosts. Historically, protozoa and helminths have been considered parasites and assumed to have a detrimental effect on the host organism. Indeed, foodborne and waterborne parasitic diseases are important worldwide, resulting in considerable morbidity and mortality. However, while the focus remains on pathogens that have been investigated from a parasitological point of view, the eukaryotic residents of the gut are often commensal (i.e., benefiting from interacting with the host without affecting it) or even beneficial.

For example, even though some helminths can cause severe illness, infections are often asymptomatic, probably reflecting a long coevolutionary history (since at least 500 million years) and tolerance of these parasites by humans. Similarly, although the best-known protozoan microorganisms found in the human gut are pathogens (i.e., Cryptosporidium spp., Giardia intestinalis, Entamoeba histolytica), it is important to remember that many protozoa, in particular Blastocystis spp., can be found with high prevalence in healthy populations, and are common (and likely ancient) members of healthy microbiomes. Indeed, although protozoan cysts are not as resistant to decay as helminth eggs, they can be found in coprolites, confirming that protozoa, like helminths, were part of our ancestral gut community. 

Interestingly, recent findings also showed that the presence of commensal protozoa (Entamoeba spp. other than Entamoeba histolytica) was strongly associated with increased diversity and various shifts in composition of the gut bacterial microbiota in rural nonindustrialized populations. Higher diversity has also been found in subjects carrying Blastocystis spp., one of the few protozoa to be present at appreciable frequency in industrialized populations. These results suggest similarities between helminths and protozoa in their effect on the gut bacterial microbiome, and raise the possibility of a potentially beneficial effect of (some) protozoa on human health.

Here, we argue that some intestinal protozoan inhabitants could play an important, yet largely unrecognized, role in shaping the gut bacterial microbiota and in maintaining the host–microbe equilibrium, and they should be considered as ‘friends’ of the human gut.

Entamoeba coli - a non-pathogenic species that frequently lives as a commensal parasite in the human gastrointestinal tract. Credit: Wikipedia.