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Credit: NSF

Once again it is summer – the weather is hot, flowers are blooming, and pesticide application signs appear on lawns throughout the United States.

Americans love their lawns, and there seems to be a national obsession for one that looks like a lush weed-free carpet. Lawns can be thought of as the largest crop in the country, since they cover more area than any irrigated crop, even more than corn.

This has led to Americans applying nearly 80 million pounds of lawn care pesticides each year. One of the most common weed-killers is 2,4-D, a chemical used in Agent Orange, and linked to several types of cancers. It is found in many weed and feed products.

There are different types of pesticides. Harmless sounding “weed-killers” are actually herbicides, and “bug-killers” and “bug sprays” are insecticides. The purpose of pesticides is to kill or repel whatever is viewed as a pest, whether insects or weeds. Lawn care pesticides are considered to be “cosmetic” or non-essential use pesticides – meaning they are only used for aesthetic purposes.

There is a dark side to pesticides

Unfortunately, pesticides have effects beyond whatever was targeted. We may not see or smell pesticides after they have dried, whether applied to our lawns, gardens, crops, or homes, but they are still there and getting into our bodies.

We can breathe them in, absorb them through our skin and eyes, and ingest them in food, water, and dust. When children and pets are walking or rolling around on the grass after a pesticide application, they are absorbing those chemicals into their bodies. As far back as the early 1990s, studies showed that pesticides such as 2,4-D get into people and pets walking on treated lawns, especially on the first day they are sprayed (applied).

Pesticides are found in our air, water, soil, “drift” from neighboring properties and farms, and even in rain and fog. We track pesticides into our homes from the outside, where they linger in house dust and carpets. Scary, isn’t it?

Every year more evidence accumulates that pesticide exposures have harmful effects on humans, pets, wildlife, birds, bees, and other beneficial insects. Even on microbes in the soil, as well as microbes in the human gut microbiome!

Exposure to pesticides can be acute – a big amount at once, such as when a toddler walks over a recently treated lawn and winds up severely ill and possibly hospitalized. Yes, that actually happened to a child in my town. Or exposure to pesticides can be continuous and at low levels (chronic exposure).

Did you know that over 90% of all Americans, including pregnant women, have pesticide residues in their bodies? Pesticides can be measured in our blood and urine, breast milk, and even meconium (an infant's first feces). Studies show that while we are being exposed less to some now banned pesticides, other pesticide levels, such as glyphosate (which is used in Roundup), are rapidly increasing in human bodies.

The bad news is that we don’t really know what all the chronic low-level pesticide mixtures that we are exposed to are doing to us. Studies are finding health problems such as cancers, endocrine (hormone) disruption, reproductive problems, effects on mental development and behavior, and even effects on semen quality. Being exposed to pesticides at certain times of development can have the biggest effects, especially during pregnancy when the fetus is developing and during childhood.

The American Academy of Pediatrics issued a statement in December 2012 warning of the dangers of pesticide exposure (including in the home) to children and during pregnancy. They stated that this includes common pesticides considered by many as “safe”, such as pyrethroids.

Our pets are at risk too. Dogs exposed to lawn pesticides develop the same cancers as humans. Researchers consider them early warning systems for human health because cancers take only a few years to show up in dogs, but many years in humans. ...continue reading "Are Lawn and Garden Pesticides Harming Us?"

It has long been known that children living in congested cities have higher rates of asthma. All those vehicles, all that pollution. A recent study found that prenatal air pollution exposure is also important in asthma development.

Pregnant women exposed to high levels of tiny ultra-fine particles (UFPs, <0.1 µm) in the air were more likely to have children who developed asthma in the preschool years. Both boys and girls were affected, but high levels seemed to be especially harmful for girl babies exposed late in pregnancy.

Many of the women lived near major roadways with high traffic density - exposure to ultra-fine particles is greater there.

Ultra-fine particles are so small (<0.1 µm) that they can be considered nanoparticles. Their small size makes them so harmful - they can enter the lungs easily and from there travel throughout the body (including the organs), where they cause inflammation and other health effects. Unfortunately, ultra-fine particles are not regulated or routinely monitored in the United States.

From Science Daily: In utero exposure to tiny air pollution particles is linked to asthma in preschoolers

Women who were highly exposed to ultra-fine particles in air pollution during their pregnancy were more likely to have children who developed asthma, according to a study published in the American Journal of Respiratory and Critical Care Medicine in May. ...continue reading "Pregnancy and Air Pollution Linked to Asthma in the Children"

The millions of bacteria, fungi, viruses (human microbiome) that live on and within us are extremely important for our health in all sorts of ways. The birth experience (as the baby travels down the birth canal) is one way that a mother's microbes get transmitted to the baby ("seeds" the baby's microbiome). But babies born by Cesarean delivery start out picking up different species of microbes - from dust in the operating room.

Thus there has been concern with the possibility that a baby born by C-section, as compared to a vaginal delivery, will have life long microbiome differences. Swedish researchers studied this issue in 471 children and determined that by 5 years of age that the microbiome differences at birth and first year of life have generally disappeared. The differences in microbial composition had decreased to less than 2% in the 2 groups. This is good news!

Over the 5 years everyone had a great increase in the number of microbial species that live in the gut. The gut microbiome became more "adult-like", but it wasn't yet like that of adults. A conclusion was that not only does it take years to develop adult microbial complexity, but there is also individual variation in how long this takes. A person's diet, especially the introduction of solid foods, and environment all have an effect on species diversity and composition.

By the way, another way mothers transmit hundreds of species of microbes to their babies is during nursing in the breast milk (this is great!), and these species change over time. This is a good reason to breast feed - it's not just the nutrition, but also the microbes.

From Science  Daily: Gut microbiota in Cesarean-born babies catches up

Infants born by cesarean section have a relatively meager array of bacteria in the gut. But by the age of three to five years they are broadly in line with their peers. This is shown by a study that also shows that it takes a remarkably long time for the mature intestinal microbiota to get established.  ...continue reading "Five Year Olds Have Similar Gut Microbes, No Matter the Type of Birth"

Evidence is building that caffeine should be avoided during pregnancy because it harms the developing baby. A recent study found when caffeine (coffee!) is consumed during pregnancy, then structural changes occur in the brain of the developing baby. These changes can be seen years later in brain scans, and these appear to result in behavioral changes in the children. The minimal, but noticeable behavioral changes were behavioral issues, attention difficulties, and hyperactivity.

The Univ. of Rochester School of Medicine and Dentistry researchers  found subtle changes in brain pathways ("alteration of the microstructure of critical fiber tracts") between brain regions that could be seen in the children at age 9 to 10 years. They analyzed brain scans (from MRIs) of 9157 children, of which 4,135 had mothers that reported consuming caffeine more than once a week.

Other studies find that health problems associated with caffeine (coffee) intake during pregnancy are miscarriage, stillbirth, low birth weight and/or small for gestational age, and childhood leukemia. There is a dose-response effect - the more caffeine is ingested, the more negative health effects.

Other human studies looking at this issue are observational, but negative health effects are supported by animal research going back more than four decades. Caffeine crosses the placenta and goes to the baby. Negative health effects occur because the fetus can not clear the caffeine well because it lacks an enzyme that metabolizes caffeine.

Unfortunately, medical guidelines in both the US and Europe are that moderate (up to 200 mg) ingestion of caffeine during pregnancy is OK, which means about 2 cups of regular coffee a day. Since studies show it's not OK, it's time to revise the guidelines!

From Science Daily: Brain changed by caffeine in utero

New research finds caffeine consumed during pregnancy can change important brain pathways that could lead to behavioral problems later in life. Researchers in the Del Monte Institute for Neuroscience at the University of Rochester Medical Center (URMC) analyzed thousands of brain scans of nine and ten-year-olds, and revealed changes in the brain structure in children who were exposed to caffeine in utero.  ...continue reading "Avoid Caffeine During Pregnancy"

Breastfeeding
Credit: Wikimedia Commons/ Anton Nosik

For years it has been known that breast milk transfers hundreds of microbial species to the baby -  which is very important and beneficial for the baby's microbiome (community of fungi, viruses, bacteria, and other microbes) and health. A recent study found that the bacteria in breast milk varies over time, which is a good reason to breastfeed for at least 6 months - the baby ingests all these beneficial species in the breast milk.

Breast milk samples were collected from 76 breastfeeding (lactating) mothers living in 8 villages in the remote Western Highlands of Guatemala during "early lactation" (6–46 days postpartum) or after months of breastfeeding or "late lactation" (109 to184 days postpartum). Modern technologies (genetic sequencing) were used to analyze the breast milk.

The researchers found a bacterial or microbiome shift from Staphylococcus and several Streptococcus species in early lactation to Sphingobium and Pseudomonas species in late lactation, along with other bacterial shifts. The changing bacterial species have different roles in the body. There were even species never before reported in breast milk, such as: Janthinobacterium agaricidamnosum, Novosphingobium clariflavumm, Ottowia beijingensis, and Flavobacterium cucumis.

Of course much is still unknown about the breastmilk microbiome, and even what is a "core" breast milk microbiome - that is, what species are the core species in all breast milk. But it's clear what the baby gets from the breast milk changes over time.  It's still early days in this research!

Note that all these hundreds of species are not those found in probiotic supplements or formula - a baby must breastfeed to get them. Unfortunately, it is estimated that only 26% of North American mothers breastfeed their babies for at least 6 months (Unicef data).

From Futurity: Breast Milk Offers Different Bacteria Over Time

This bacterial cocktail could act like a daily booster shot for infant immunity and metabolism. ...continue reading "The Bacteria In Breast Milk Change Over Time"

Many people don't realize that the plastic toys our children play with may contain harmful chemicals. Children get exposed to these chemicals by touching the toy (absorption through the skin), or ingesting chemicals (e.g. when a baby mouths the toy, or child ingests dust from the toy), but also from breathing in chemicals leaching out of all the plastic toys in the room into the air. This has been known a long time, yet here we are...

An international team of researchers looked at 419 chemicals and found 126 chemicals of concern (chemicals known to be harmful) in plastic toys - chemicals that they felt should no longer be used in children's toys. Many are endocrine disruptors, while others are linked to cancer. In this group were 31 plasticizer chemicals (including phthalates and BPA [bisphenol]), 18 flame retardants, and 8 fragrances. These chemicals can be measured in the urine. [Note: they did not look at some chemicals, such as lead, cadmium, arsenic, etc.]

The researchers conclude: "Nowadays, existing regulations mainly prioritize a small set of chemicals, and regulators struggle to keep up with the thousands of new chemicals entering the market every year." They stress that we need to avoid "regrettable substitution" (substituting a dangerous chemical with another equally dangerous related chemical - such as replacing BPA with BPS). We need to identify safer substances that can be used in toys.

The more plastic toys in a room, the more exposure. They are outgassing all the time - even if you can't smell it. Soft plastic toys emit (outgas) the most chemicals. Children are especially vulnerable to these chemicals. Currently there is no international agreement over which chemicals to ban or regulate, and not enough chemicals are regulated or banned in toys and children's products.

There is no way right now to know which plastic toys contain dangerous chemicals and which don't. Toy manufacturers do not tell us what chemicals are in the toys. So... yes, we absolutely need (global) regulations to totally ban the use of certain chemicals in plastic toys, especially because so many toys are produced in countries with weak environmental regulations. We need to use safer chemical alternatives in plastic toys.

Bottom line: Try to have fewer plastic toys, especially soft plastic toys. Try to ventilate rooms frequently (every day) by opening windows, even if only for a short while.

From Science Daily: Potentially harmful chemicals found in plastic toys

It has long been known that several chemicals used in plastic toys in different parts of the world can be harmful to human health. However, it is difficult for parents to figure out how to avoid plastic toys containing chemicals that may cause possible health risks to their children.   ...continue reading "Plastic Toys May Contain Harmful Chemicals"

Have you wondered whether a totally vegan diet for young children is healthy? Are they missing nutrients? A study from Finland attempted to answer this question by comparing young children eating vegan diets with those eating vegetarian and omnivore (both meat and plants) diets. A vegan diet contains no animal products, including eggs and dairy.

The researchers studied 40 healthy Finnish children, average age 3 1/2 years. They found that a vegan diet, even with recommended levels of supplementation (vitamin B12, iodine, vitamin D), resulted in significant effects on the children's metabolism and lower levels of certain nutrients, such as Vitamin A, vitamin D, and retinol-binding proteins (RBP). The vegan children also had a lower protein intake and lower levels of essential amino acids.

A vegan diet is practically devoid of cholesterol, EPA, and DHA, and so the children had significantly lower total cholesterol, HDL, LDL, and DHA (docosahexanoic acid) levels. DHA is a fatty acid needed for development of visual function. The researchers were concerned about the visual health of the vegan children due to the combination of low vitamin A and DHA levels. On the other hand, folate levels were high in the vegan children.

It is interesting that these differences occurred, even though all the children received nutritionist planned daily meals at high quality day care. The intake of vitamins D and A were the same in the different groups. All vegan children had followed a vegan diet since birth and were breastfed for 13–50 months by vegan mothers.

The researchers said that while a vegan diet is generally viewed as having health benefits in adulthood, they have concerns with a vegan diet for young developing children. The vegan children had low cholesterol levels, but the researchers said cholesterol is "essential for cellular growth, division, and development of physiological systems due to its major role in the synthesis of cell membranes, steroid hormones, bile acids, and brain myelin".

We currently don't know long-term health effects (whether good or bad) of a strict vegan diet from birth. Studies are needed! But we do know that young developing children need cholesterol. Another very important nutrient that may be lacking in vegan diets is choline, which is critical for brain health - a good source is eggs.

From Science Daily: Vegan diet significantly remodels metabolism in young children

The study concludes that vegan diet has a broad effect on children's metabolism. Serum biomarker levels for vitamins A and D, cholesterol forms and essential amino acids were significantly lower in children on vegan diet compared to age-adjusted omnivores. In addition, docosahexaenoic acid is absent from vegan diet. The results were recently published in a high-profile international scientific journal EMBO Molecular Medicine.  ...continue reading "Some Concerns With A Vegan Diet In Young Children"

Breastfeeding
Wikimedia Commons/ Anton Nosik

There are a lot of health reasons why breast milk is better for a baby then formula, and now another reason can be added to the list. A recent study found that specific immune cells (regulatory T cells) expand more in the first three weeks of life in breastfed human babies - nearly twice as abundant as in formula fed babies.

These cells control the baby's immune response against maternal cells transferred with breast milk and help reduce inflammation. In other words, breast milk is good for the baby's immune system development.

The University of Birmingham researchers also found that specific beneficial bacteria, called Veillonella and Gemella, which support the function of regulatory T cells, are more abundant in the gut of breastfed babies.

Breast milk is considered the best food for infants. It contains a range of complex nutrients, antimicrobial proteins, bacteria, human milk oligosaccharides, and hormones from the mother. Thus it isn't surprising that whether the baby receives breast milk or formula influences the gut microbiome (community of microbes in the gut).

From Science Daily: New insight into why breastfed babies have improved immune systems

Research led by the University of Birmingham and Birmingham Women's and Children's NHS Foundation Trust has revealed new insight into the biological mechanisms of the long-term positive health effects of breastfeeding in preventing disorders of the immune system in later life.  ...continue reading "Beneficial Effect of Breast Milk On the Baby’s Immune System"

There is much concern nowadays about all the many chemicals we are exposed to in our lives. These include pesticides, heavy metals (e.g. lead, mercury), and chemicals that act as endocrine disruptors (hormone disrupting chemicals), such as BPA and phthalates. These chemicals are all around us and are linked to all sorts of health effects, including chronic diseases and reproductive effects - such as infertility, declining sperm counts, adverse effects on the developing baby, and endometriosis.

There is an excellent 7 part series of webinars that one can watch called Generation Chemical: How Environmental Exposures are Affecting Reproductive Health and Development. Big names in the field discuss the latest science on the impact of harmful chemicals and pollutants on female and male reproductive health, pregnancy, and development, starting from preconception and through  life.

Yes, it's in depth, but also eye-opening. For example, the evidence is now raising the questions: Are fertile people healthier? Does poor sperm quality mean poorer health? Or earlier death? Research suggests that sperm count and quality are "canaries in the coal mine" for male health - evidence of harm to men from environmental and lifestyle influences.

Also, keep in mind that while you can't totally avoid harmful chemicals, you can really minimize your exposure and the levels measured in you. Avoiding Harmful Chemicals gives good ways to reduce exposures to harmful chemicals. This is especially important for both males and females if thinking about conception or pregnant.

SEVEN PART WEBINAR SERIES: 1) Introduction. Oct. 29, 2020. Discussed declining sperm counts that have been occurring worldwide over the last few decades - 52.4% decline in 38 years among men from Western countries, and the decline is still continuing. Effects of endocrine disrupting chemicals (EDCs) on men's and women's fertility, conception delay, pregnancy loss, some diseases, and endometriosis. ...continue reading "Top Scientists Explain How Harmful Chemicals Are Affecting Reproductive Health and Development"

It turns out that plastic baby bottles shed millions of tiny plastic particles (microplastics) into the breast milk, formula, or water in them. At this point we don't really know what ingesting multitudes of microplastics every day does to a person, but assume that it is not beneficial and we should try to lower how much we ingest. (Microplastics are turning up in foods and water, especially bottled water - we are ingesting them, excreting them, and there is some concerning health research.)

Trinity College researchers found that the greatest number of microplastics are shed into the baby bottle contents when polypropylene bottles are heated, especially during bottle sterilization. The research team estimated that current guidelines for infant bottle sterilization and formula preparation result in an average daily ingestion by European and American babies of more than 2 million microplastics every day! Yikes!

What to do? Absolute best would be to use glass baby bottles - no plastic there. But if plastic baby bottles are used: 1) first sterilize the bottles. 2) Then rinse the sterilized bottles 3 times in water that has been sterilized (boiled and cooled) in a stainless steel or glass pot. 3) Same with the formula - heat in a non-plastic container (glass or stainless steel) and then pour it into the plastic baby bottle.

Also: do not heat formula in plastic containers or microwave ovens. Do not vigorously shake the formula in the bottle at any time. Do not use sonication to clean plastic baby bottles.

Shedding of microplastics is a property of plastic polypropylene bottles, and the hotter the bottle - the more is shed. Shaking also releases microplastics. The only way to avoid the problem of microplastics in the formula or other liquid is to use glass baby bottles.

From The Scientist: Baby Bottles Can Shed Millions of Microplastic Particles: Study

Plastic has long been a major source of pollution in landfills and in oceans, especially as it degrades into pieces smaller than 5 millimeters, termed “microplastics.” Experimental studies have shown that these particles and the cocktail of chemicals they carry can wreak havoc on physiology, reproduction, development, and behavior in a number of nonhuman species.  ...continue reading "Plastic Baby Bottles Shed Tiny Plastic Particles"