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Several recent studies have highlighted the negative effects of air pollution on the brain, specifically from the tiniest particles in polluted air (called PM 2.5). These tiny particles get to the human brain and cause all sorts of damage. Even at levels within government guidelines.

Two studies found that with higher chronic (daily) exposure to PM2.5 air pollution there were structural changes to the brain. Which is negative to brain health, of course.

With chronic exposure to higher levels of  PM2.5 air pollution: one study found greater declines in memory and more Alzheimer's-like brain atrophy in older women in the USA; and the second study found that higher prenatal exposure was associated with a smaller corpus callosum (a part of the brain) later in childhood. Thus structural changes in the brain!

The tiniest particles are 2.5 micrometers or less in diameter, about 1/30th the width of human hair - and referred to as PM2.5. These fine particles are produced by all sorts of combustion, including motor vehicles, power plants, residential wood burning, agricultural burning, some industrial processes, and forest fires. Typically there is much more exposure to PM2.5 in busy urban streets, and less in quiet suburban streets.

Researchers in Barcelona, Spain found that long-term higher prenatal exposure to PM2.5 particulate matter, especially during the last trimester of pregnancy, is associated with a smaller corpus callosum in children between the ages of 8 and 12 years. This is an important finding because a smaller (reduced volume) corpus callosum is found in ADHD (attention deficit hyperactivity disorder), ASD (autism spectrum disorder), and hyperactivity. So here we see a structural change in the brain from air pollution at PM2.5 levels that are considered acceptable (within guidelines) by the European Union!

A report called The State of Global Air/2018 stated that studies show that long-term exposure to PM2.5  particles in the air "is the most consistent and robust predictor" of death from heart disease and stroke, lung cancer, and respiratory illnesses. And then there are nitrogen oxides and ozone, which are also linked to death. There are also nanoparticles (e.g., from friction of tires being used) that penetrate deep into the human body.

A 2018 The Guardian article called air pollution "the new tobacco". And that it's time to tackle this epidemic. Yup. Unfortunately, current air pollution standards are being relaxed in all sorts of ways under the current U.S. administration. Beware!

First study. Excerpts from Medical Xpress: Exposure to PM 2.5 pollution linked to brain atrophy, memory decline  ...continue reading "Air Pollution and the Brain, Part 1"

The evidence is building, study by study, that we are all exposed to a mixture of hormone disrupting chemicals (endocrine disruptors) on a daily basis, and that these have serious health effects, including on the developing fetus during pregnancy. Researchers found that early prenatal exposure to a mixture of endocrine disrupting chemicals  was associated with lower levels of cognitive functioning (lower IQ scores) at age seven, particularly among boys.

Researchers in New York City and Sweden looked at the impact of 26 endocrine disrupting chemicals during pregnancy on 718 Swedish mother-child pairs. It appeared that the higher the exposure during pregnancy, the more of an effect at age 7. Especially harmful was the BPA replacement chemical BPF - this is because it is chemically related to BPA.

Endocrine disrupting chemicals (EDCs) include bisphenols (BPA and its replacement  chemicals, such as BPF - used in products called "BPA free"), phthalates (especially used in vinyl products), parabens, chemicals used in flame retardants and non-stick coatings,  and some pesticides (e.g. the commonly used chlorpyrifos).

Especially worrisome is that while scientists typically test chemicals one at a time to determine their safety, in the real world we are all exposed to mixtures of these chemicals in our food, consumer products (including personal care products and cosmetics), and environment. Some of these chemicals can cross the placenta during pregnancy and so have an effect on the developing the fetus, including brain and neurological development. Yes, some of these chemicals are only in the body for a short time, but during critical developmental  stages, the effects can be big - even at very low exposures.

Bottom line: If trying to conceive a child or during pregnancy, try to minimize exposure to plastics, pesticides, flame retardants, non-stick cookware, stain-proofing (in fabric and rugs), fragrances and scented products (including air fresheners and dryer sheets), and food stored in cans and plastic containers. Avoid triclosan, anti-odor, antibacterial, anti-germ products and clothing. Avoid parabens (in lotions, etc). Read labels. Glass and stainless steel is perfectly fine. Use unscented or fragrance free products as much as possible.

From Medical Xpress: Chemicals in consumer products during early pregnancy related to lower IQ   ...continue reading "Pregnancy, Endocrine Disrupting Chemicals, and Lower IQ"

Two recent studies point out the dangers of air pollution to the developing fetus. The first study found an association with high levels of air pollution during pregnancy and lower IQ years later when the children were between the ages of 4 to 6 (as compared to women exposed to less traffic-related air pollution during pregnancy).

The second study found that soot (tiny carbon particles) from air pollution  (e.g. vehicle exhaust) are breathed in by the pregnant woman, and then make it to her placenta during pregnancy and cross over to the baby's side of the placenta. (The placentas were collected and examined after delivery.) The fact that these tiny particles found in polluted air are breathed in by the pregnant woman and reach the baby's side of the placenta and accumulate, suggests to the researchers how air pollution causes harm to the fetus. They also found that the more particles the pregnant woman was exposed to throughout pregnancy, the more particles were detected on the baby's side of the placenta ("placental load").

The placenta used to be viewed as a barrier to toxins, but NOPE - it's not. (As we already know with alcohol and drugs, etc.)

But now some good news: In the first study, pregnant women who had higher levels of folate in their blood - meaning they had better nutrition and higher intake of folic acid during pregnancy, appeared to have a protective effect on the developing baby. As the researchers said: "Maternal folate levels may modify the impact of prenatal air pollution exposure on child cognition." In those with the lowest folate levels during pregnancy, the negative effects of air pollution during pregnancy on the developing fetus appeared to be the strongest (6.8 points lower IQ). Folate is naturally occurring in many fruits, vegetables, beans, peas, and nuts, and is in the form of folic acid in vitamin supplements. Best is a good diet.

From Medical Xpress: Offspring of pregnant women exposed to high level of pollutants may have lower IQs   ...continue reading "Air Pollution Has Harmful Effects During Pregnancy"

Pesticides are harmful to developing brains, especially during pregnancy. A number of studies have already found that higher exposure to organophosphate pesticides during pregnancy is linked to poorer cognitive functioning and behavior problems in children. A recent University of California study actually looked at the brain activity in 95 teenagers while they were doing a number of mental tasks. Using advanced brain imaging, they found altered brain activity in those teens who had the highest organophosphate pesticide exposure prenatally. These teenagers live in Salinas Valley, California - an agricultural area with many farms.

The researchers point out that "Over 800 million pounds of pesticide active ingredients are applied in the United States each year, with organophosphates (OPs) the most commonly applied class of insecticides. Exposure to OP pesticides, which are endocrine-disrupting compounds, is widespread in the US population, including among pregnant women and children." [PLEASE NOTE: Conventional farming uses organophosphates. Organic farming does not allow the use of organophosphates.]

The main way people get exposed to organophosphate pesticides is diet - especially pesticide residues on fruits and vegetables. Also, if people live near farms where such pesticides are used, or live with a person who works on a farm. They bring home the pesticides on their clothes. People also breathe breathe in pesticides when they are applied on nearby farms or properties due to pesticide drift.

Chlorpyrifos is one example of an organophosphate pesticide. It is considered so dangerous to the developing fetus and children (lower IQs, neurological effects, behavioral effects) that the EPA was going to ban it in the United States. However, the Trump administration overruled the ban (chemical/pesticide lobbyists at work!). Since then, several states (NY, Hawaii, California) have enacted legislation to ban all use of chlorpyrifos in those states, but it will take several years for the bans to become fully in effect.

From Science Daily: Prenatal pesticide exposure linked to changes in teen's brain activity   ...continue reading "Certain Pesticides Linked to Altered Brain Activity In Teenagers"

For years there has been a debate about whether adding  fluoride to drinking water was a plus (less tooth decay) versus those who felt there were possible health problems from the fluoride.  Now the results of a Canadian study is raising serious concerns. The researchers followed 601 pregnant women from 6 cities in Canada, and found that pregnant women with higher levels of fluoride in their urine tended to have children with lower average IQs (which was measured at 3 or 4 years of age). As in the USA, some communities added fluoride to municipal drinking water, while others didn't.

The problem is that: "Fluoride crosses the placenta, and laboratory studies show that it accumulates in brain regions involved in learning and memory, and alters proteins and neurotransmitters in the central nervous system." Not good. This is why studies are being done.

The researchers concluded the study with these words: "In this prospective birth cohort study from 6 cities in Canada, higher levels of fluoride exposure during pregnancy were associated with lower IQ scores in children measured at age 3 to 4 years. These findings were observed at fluoride levels typically found in white North American women. This indicates the possible need to reduce fluoride intake during pregnancy." [Note: in this study, the effect appeared to be stronger in boys than girls.]

Just note that this was an observational study (found an association, not a definite cause), but other studies also find such an association. (One study conducted in Mexico found that higher prenatal fluoride exposure was linked to lower IQs in 4 to 6 year old children.) Of course more studies are needed.

But in the meantime, one can try to lower fluoride exposure (in water) during pregnancy. One way is to drink less black tea (has high levels of fluoride) and green tea (varying levels of fluoride). Also, if fluoride is added to tap water, to try to drink less of that and perhaps more unfluoridated bottled water that is in glass bottles (because plastic leaches, and has more microplastics in it).

From The Scientist: Fluoride Exposure During Pregnancy Linked to Lower IQ In Sons   ...continue reading "Fluoridated Drinking Water and Pregnancy"

Good news for those wondering if home births are as safe as hospital births. An international study says the answer is YES, for low-risk women who begin labor intending to give birth at home as compared to low-risk women intending to give birth in a hospital. Canadian researchers analyzed data from 14 international studies (including about 500,000 women planning on home births). A midwife was present at each birth. The risk of perinatal or neonatal death was not different when birth was intended at home or in hospital. The researchers defined perinatal death as stillbirth after labor starts through day 7 after birth. Neonatal death is defined as death after birth of a live baby from day 0 through day 28.

The researchers pointed out that the best outcomes are when birth attendants are integrated into the health care system, and there was a smooth transition from home to hospital when needed. In their analysis they included studies looking at births in England, Netherlands, Norway, Sweden, Iceland, Canada, USA, Japan, Australia, and New Zealand.

From Science Daily: Home births as safe as hospital births: International study suggests  ...continue reading "Are Home Births As Safe As Hospital Births?"

Two years ago scientists reported an alarming and steep decline in sperm counts in men from Western industrialized countries over the last 40 years. Both sperm count and sperm concentration declined 50 to 60% in this period in men in North America, Europe, Australia, and New Zealand. Especially concerning was that there was no evidence of this year by year decline leveling off.

What does this mean? As these declines continue, more and more men will have sperm counts below the point at which they can reproduce. Instead they will be infertile or "sub-fertile" (fertilization is unlikely). According to the World Health Organization (WHO), a sperm count of below 15 million per ml makes a man subfertile. However, also of concern is the threshold level associated with a "decreased monthly probability of conception", which is 40 million/ml - which means conception will take significantly longer (due to impaired ability to fertilize an egg).

A recent Univ. of Geneva study looked at semen quality of 2523 young men (aged 18 to 22 years old) who were being drafted into the military in Switzerland. They found that average sperm quality and sperm concentration of the men, who were from all regions of Switzerland, was among the lowest in Europe (along with Germany, Denmark, and Norway).

In Europe, median sperm count ranges from 41 to 67 million per milliliter (ml), depending on the country. The researchers found that the group of Swiss men had a median sperm count of 48 million per ml. And 17 percent of the men had sperm counts below 15 million per ml (thus subfertile). By the way, countries with lower sperm counts and quality, have higher rates of testicular cancer - they go hand in hand.

Also, in a quarter of the Swiss men studied, less than 40 percent of sperm cells were motile (moved normally), and 43 percent of men had less than 4 percent normally formed sperm. Overall, only 38 percent of Swiss men had healthy sperm - that is, with concentration, motility, and morphology (shape, form) that met the WHO’s criteria for healthy sperm.

Why is this happening? The researchers found that of the men with very low sperm concentration, more of their mothers smoked during the pregnancy, which means there could be changes during embryonic development. Also, while this study did not discuss this, many other researchers say that sperm health is "the canary in the mine" for male health - evidence of harm to men from environmental and lifestyle influences. 

These Western developed countries are awash in chemicals and plastics, also with endocrine disruptors (hormone disruptors) in our foods, our personal care products, in products all around us - and so studies find these chemicals in all of us (in varying degrees). Same with flame retardants, pesticides, "scented" products. Exposure to all sorts of environmental pollutants - whether in air, water, soil, our food - such as high levels of aluminum. All of these can have an effect on sperm counts and reproductive health. You can't totally avoid these chemicals, but you can try to lower your amounts of exposure (some tips to lower exposures).

From Medical Xpress: Poor semen quality in Switzerland   ...continue reading "Male Fertility Is Plunging In Switzerland"

For a few years I've been noticing that studies of vitamin D have had mixed results for a number of medical conditions. A number of times initial studies found an association with low levels of vitamin D and a number of medical conditions, but follow up well-designed studies are just not finding the same results with vitamin D supplementation - or results have been mixed. Also, in some studies, what initially looked like vitamin D being protective for some cancers and multiple sclerosis, now looks like it's sunlight that is giving the protective results. In some cases, vitamin D levels are a proxy for sunlight exposure (the more sunlight exposure, the higher the vitamin D levels in the person). The following 6 studies recently published highlight this same trend of mixed results.

While vitamin D levels increased from high dose vitamin D, there was no change in bone bone mineral density (BMD) in older adults during the 12 months of the study. No adverse effects form the vitamin D supplementation was reported [the older adults received 12,000 international units (IU), 24,000 IU, or 48,000 IU once a month]. From Science Daily: Vitamin D supplements are of no benefit to the over 70s

There is little benefit for those over 70 taking higher dose vitamin D supplements to improve their bone strength and reduce the risk of falls, new research has revealed.

High doses of vitamin D (4000 international units) appeared more beneficial than low dose vitamin D (400 international units) supplements in advanced colorectal cancer patients. From Medical Xpess: High-dose vitamin D shows benefit in patients with advanced colorectal cancer

...continue reading "Recent Vitamin D Studies Have Mixed Results"

Many of us have concerns over the fact that people are constantly exposed to endocrine disruptors (chemicals that disrupt hormonal systems) in many common household and personal products. Even the vinyl flooring found in many homes  contains phthalates, which are endocrine disrupting chemicals. In the past year several studies have looked at vinyl flooring in homes and whether the chemicals in the flooring outgas into the air and then get into people living in the homes. The answer is YES - the chemicals in vinyl flooring do get into people living there, and they can be measured in urine (in the breakdown products of phthalates called metabolites).

Since research shows that endocrine disrupting chemicals have health effects, then the question is: Do chronic low levels do anything to people? Especially worrisome is, are they having an effect on the developing fetus when pregnant women are exposed to them and they get into the body? The following 2 studies looked at flooring, but keep in mind that we are exposed to phthalates in many, many products - e.g., plastic shower curtains, plastic food containers, some personal care products, household products. The problem is that the pthalates migrate out of the plastic products - they don't stay in the product. In the case of vinyl flooring - one can say that there are phthalate emissions from the flooring! And of course it gets into household dust.

Numerous studies found that phthalates (the phthalate metabolites) are routinely found in people of all ages - throughout the world. It can be measured in our blood (serum) and in our urine. Studies find them in breastmilk and also in amniotic fluid. Research finds associations associations between exposure to several phthalates and various effects on human health, including reproductive effects.

The following are two complementary studies. Study 1 looked at vinyl flooring (called PVC flooring in the article) in homes (in the kitchen and bedrooms), and found that phthalates get into pregnant women, and can be measured in the urine. Study 2 (from Duke University), found that chemicals children are exposed to in the home from vinyl flooring and the sofa (flame-retardants) can be measured in their blood and urine. The researchers took all sorts of samples from homes and children over a 3 year period and found evidence in the children of exposure to phthalates, organophosphate esters, brominated flame retardants, parabens, phenols, antibacterial agents and perfluoroalkyl and polyfluoroalkyl substances (PFAS).

So we have proof that these chemicals are getting into us. We can't avoid them totally, but can lower our exposure levels - look for upholstered furniture without flame retardants (read the label!), and don't install vinyl flooring (wood and tile floors are OK).  ...continue reading "What’s Getting Into You From Vinyl Flooring?"

To the alarm of many, male fertility (sperm quality and sperm counts) has been rapidly declining over the past few decades. Researchers suspect that it's due to our exposure to chemicals in the environment, especially to endocrine disrupting chemicals - of which there are many, and to which we are exposed to daily. A recent study found that detrimental effects occur in the sperm of both humans and dogs when exposed to the common plastic softener DEHP and the persistent industrial chemical polychlorinated biphenyl 153 (PCB153). The researchers suggest this is because dogs live in households with humans and thus are exposed to the same environmental contaminants.

DEHP (diethylhexyl phthalate) is an endocrine disruptor (interferes with hormone systems) that is found in plastic materials in many household and personal items - for example, in carpets, vinyl flooring, some upholstery, rainwear, wires, some plastic toys, fragrances and air fresheners, some PVC pipes, some food packaging, medical tubing, plastic shower curtains. The problem is that it slowly leaches out of the products and into the air and household dust, it leaches out of packaging into foods (which we then ingest), and it can also be absorbed through direct skin contact. Bottom line: try to avoid DEHP by avoiding plastics known as polyvinyl chloride (PVC) or vinyl as much as possible. (One can't totally avoid them, but can reduce exposure to them.)

From Science Daily: Chemical pollutants in the home degrade fertility in both men and dogs, study finds

New research by scientists at the University of Nottingham suggests that environmental contaminants found in the home and diet have the same adverse effects on male fertility in both humans and in domestic dogs.  ...continue reading "Common Chemical Has Negative Effects On Sperm of Both Humans and Dogs"