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The controversy over the pesticide Roundup and glyphosate (which is the active ingredient in Roundup) rages on. This week the Environmental Working Group (EWG) published results of independent laboratory tests (commissioned by them) that looked at glyphosate levels in common oat based foods (cereals, oatmeal, granola, and snack bars). Not surprisingly, they found glyphosate in almost all conventional cereals and at much higher levels than the little they found in some organic cereals (it was felt this was from cross-contamination or "pesticide drift" from conventional farms onto organic farms). The main questions are: Why is this pesticide found in foods? What, if anything, does this mean for our health? Are these levels safe?

The main thing to know: Glyphosate is the most heavily used herbicide (a type of pesticide) in the world. Over 250 million pounds were applied in the U.S. in 2015, with much of the application in the Midwest. Incredibly huge amounts of glyphosate are used in the midwest on farmland - greater than 88.6 pounds per square mile! Top crops it's used on are corn, soybeans, canola - especially genetically modified Roundup Ready crops. It is also used as a dessicant right before harvest ("preharvest") on many crops, such as wheat and oats (see Monsanto's guide for preharvest use). This is why harvested crops have glyphosate residues on them, and the foods we eat. Note that glyphosate (Roundup) can not be used on organic crops.

The herbicide has been linked to a number of health problems, including cancer, birth defects, endocrine disruption, and reproductive problems. (Posts on glyphosate.)  There are currently hundreds of lawsuits from farmers and others claiming that Roundup gave them cancer. This past week a California jury awarded $289. millions dollars to a man who said his cancer was due to repeated glyphosate weed killer (including Roundup) exposure as part of his job. A new concern is that glyphosate has an effect on our gut bacteria - that it messes with the human gut microbiome. Also, that Roundup has more of an effect than glyphosate alone (what's in all those hiddden inert ingredients?) At this point we just don't have all the answers, but there is cause for concern.

Whether these government allowed levels of pesticide residue in our foods are "safe" is also being hotly debated. The chemical industry and EPA say it's safe, while a number of researchers are saying no. It has been pointed out by many that the chemical industry (Monsanto - the makers of Roundup) and the EPA have worked hand in hand to make sure that Roundup is considered "safe".

Also, government allowable levels of glyphosate in foods (called tolerance for pesticide residue) were raised when the pesticide industry lobbied for that (which happened when Roundup Ready crops were introduced and as preharvest use increased). The EPA for years deliberately did not look at how much glyphosate residue is in our foods - if you don't know, how can you be concerned? And research now shows that MOST people have detectable glyphosate residues in them, including most pregnant women. [See all glyphosate posts.]

Both Quaker Foods and General Mills (their product Cheerios was among those with higher levels of glyphosate residues) responded to the EWG report by saying that their products are safe because the glyphosate residue levels in their products are within the EPA’s acceptable levels. Yes, but are these levels really safe? Especially if a person eats many foods with multiple pesticide residues daily.

Bottom line: We just don't know what these small, but increasing levels of glyphosate residues in our food and our bodies means for our health. If you are concerned, and I am, then try to eat organic foods when possible, especially organic corn, soybean, canola, wheat, and oats in order to try to minimize glyphosate levels in your body. Glyphosate and Roundup is not allowed to be used on organic crops. 

All the seasons are beautiful here in the northeast US, but there is a dark side to  nature - ticks. Tick numbers, types of ticks, and diseases (including Lyme disease) that people are getting from tick bites are all increasing. Nothing seems to stop their spread and their increasing numbers. While deer ticks have been a huge problem for years, now two new tick species are concerning us here in the northeast: the longhorned tick and the lone star tick.

The scary species of longhorned tick (or Haemaphysalis longicornis) was discovered in NJ in 2017, and now it appears that it is spreading rapidly (Virginia, West Virginia, Arkansas, North Carolina, NY). This tick is a native of east Asia (japan, New Zealand, Australia, etc.), and transmits a number of diseases and infests livestock in eastern Asia. It is especially worrisome because females can clone themselves - so they can appear on animals in really large numbers in varying stages. (The photos are horrifying.) The lone star tick is an aggressive tick that can march across the lawn and up onto the deck to get to humans. And its bite is linked to red meat allergies!

How are ticks spreading so rapidly in the US? Many researchers say that with a warming climate ticks are more active for longer periods of the year and can now live in places long thought that they couldn't live (e.g. at higher elevations). But there's more to it. Yes, tick species and tick-borne diseases are now spreading across the US due to warmer winters (climate change!), but research also shows that they spread  due to migratory birds carrying (and depositing) ticks along migratory paths. The huge, huge increase of deer populations in suburban areas is also spreading ticks. As well as small mammals (especially mice!). And on and on.

What to do? There are many pesticides available that can reduce tick populations (spray or apply to lawns and vegetation), but it is questionable whether it really helps. One good 2 year study found that pesticide treatments reduced the number of ticks, but not the number of human-tick encounters and it didn't reduce the number of tick-borne diseases (e.g. Lyme disease). Also, ticks like to live in "leaf litter" at the edges of the lawn and under bushes, in woods - all places hard to treat. Plus, animals and birds visiting the yard are constantly bringing more ticks to the property.

Basically the advice has generally been that it is up to the individual to prevent tick bites by applying an insecticide, or wearing clothes that have the insecticide permethrin on them, checking yourself after going outside and removing any ticks, showering after going outside (even if it's at the end of the day), changing and washing clothes (and put into the dryer to kill the little suckers) after going outside. But there is some concern about some insect repellents (e.g. DEET), especially if used frequently, and many people don't want to apply pesticides such as DEET daily on their children or themselves.

The one question that I hear the most is - are there nontoxic insecticides that are safe to use daily, especially for children? The answer is YES - a good one is Oil of Lemon Eucalyptus (OLE). My absolute favorite non-toxic insect repellent that I think is fabulous and also highly recommended by Consumer Reports as being effective against ticks (and mosquitoes) for at least 6 hours is: Repel Lemon Eucalyptus Natural Insect Repellent (comes in a pump spray). We found that it also repels other biting insects such as black flies, and washes well out of clothes, so a total win! My understanding is that the CDC (Centers for Disease Control) does not recommend it for children under the age of 3 at this time because studies on this age group have not been done.

Others also suggest some non-toxic possibilities for the yard: raise free range chickens (they eat ticks!) or guinea fowl (eat ticks, but very noisy), encourage the presence of foxes (they eat the mice, and a study found they really reduce tick populations), can throw tick tubes such as Damminix (contain cotton balls with permethrin that mice carry back to nests) into the bushes or woods around your property. And a large study in NY state is investigating a new possibility for non-toxic tick control (as described in the last post) - whether tick bait boxes (The Tick Control System) and/or applying a non-toxic tick killing fungus (the product Met52) will lower tick numbers and tick diseases. The researchers are hoping tick reductions of at least 90%! Finally some encouraging news.

Something a little different today. For years I've posted studies showing that eating organic foods lowers pesticide levels in the body quickly, eating organic foods is the only way to avoid the presence of the controversial pesticide glyphosate (Roundup) in food, the nutritional profile (especially fatty acids) of meat and milk from grass-fed, pasture raised animals is different and healthier than conventionally raised animals (and even organic animals not raised on pasture), and on and on. In other words, eating organic foods has health benefits. All good.

But meanwhile, the National Organic Program and National Organic Standards Board (which controls the national organic foods certification program) is being influenced by big agriculture lobbying - to the dismay of real organic farmers. Yes - real organic farmers, who farm the way we expect our organic meat and crops to be raised. You know - cows grazing outside, chickens pecking away for insects outside, crops being raised in real soil (and not hydroponics). But ... Big Agriculture with the mega-farms and lots of chemicals, and animals confined by the thousands indoors, have decided they want a piece of the organic action, and have now influenced the National Organic Program and National Organic Standards Board with the result of weakening of organic standards. But there are other problems too with the organic program as it currently exists.

The Washington Post did a series of articles last year about a huge issue of fraud -  about how so-called organic food from other countries may really not be organic (esp. corn and soybeans), and this mega-influx of fake organic food with lower prices is something real organic farmers in the US can't compete with. Also, how "larger agricultural companies have sought to loosen organic rules in the name of efficiency and affordability". The organic market is a big one, and growing bigger every year (billions of $$). It benefits large corporations and huge mono-crop farms financially to have watered down standards.

Another example: the organic milk that one buys may not really be organic (and the same issue with organic chickens). Organic dairies are supposed to have their dairy cows out grazing in the pasture for a minumum of 120 days per year - it is a requirement. But big dairies that are only organic in name ignore that requirement - such as the huge Aurora Dairy. Yup, they lie. And in September 2017, the USDA (US Department of Agriculture) didn't punish the 15,000 cow Aurora Dairy - instead they "exonerated the enormous Aurora Dairy CAFO (Confinement Animal Feeding Operation) of any wrongdoing at their Colorado “farm.” This dairy operation was described in detail in one Washington Post article, along with compelling test results to prove the cattle weren’t on pasture." So of course now they and other mega-dairies will just ignore the organic regulations, because they can without any penalty...continue reading "Is A New Organic Label Needed For Farmers Following Traditional Organic Practices?"

Wondering which fruits and vegetables have the most pesticide residues? The annual Dirty Dozen List of produce with the most pesticide residues has once again been published by the Environmental Working Group (EWG). They suggest that these fruits and vegetables are good candidates for buying organic.

Why organic? Because while almost 70 % of the produce sampled by the Federal Government had pesticide residues, some have more than others. For example: about one-third of the strawberries sampled contained 10 or more pesticides. Yikes! The following article also discusses some recent reproductive research and  pesticides on food, as well as EWG's "Clean Fifteen" list of fruits and vegetables with the least pesticide residues. (See more PESTICIDE posts.) From Environmental Health News:

Report calls out worst produce for pesticides—strawberries, spinach top list

Just when you thought it couldn't get any harder to eat healthy. Turns out those nutrient packed foods we're all told to eat—such as strawberries and spinach— are also consistently tainted with potentially harmful pesticides. Both foods top the "Dirty Dozen" list released today by the Environmental Working Group (EWG), which analyzed federal data on pesticides in produce.

EWG, which examined tests done over the past few years by the U.S. Department of Agriculture, reports almost 70 percent of the produce sampled by the feds had pesticide residues. Some were worse than others: "More than 98 percent of samples of strawberries, spinach, peaches, nectarines, cherries and apples tested positive for residue of at least one pesticide," according to the report.  ...continue reading "Fruits, Vegetables, and Pesticide Residues"

A recent study of pregnant women found new health problems with the pesticide glyphosate, which is the active ingredient in the weedkiller Roundup (made by Monsanto). The researchers found that women  with higher levels of glyphosate are more likely to have shorter pregnancies. Another major finding was that almost all the pregnant women (93%) in this study had detectable levels of glyphosate in their urine. I posted about this study earlier, but now it has been published in the journal Environmental Health.

All the pregnant women were living in central Indiana (in the cornbelt) in a mix of areas (suburban, urban, and rural), and whether they had well or public drinking water. In case you don't know, it is not good for a baby to be born early, and there can be lifelong health consequences - so every extra week (till full term) is good during pregnancy. The researchers found higher levels of glyphosate in women living in rural areas (farm areas) and those drinking greater than 24 ounces a day of caffeinated beverages. The researchers thought that diet (food) and inhalation of contaminated dust were the major ways that the glyphosate got into the pregnant women.

Glyphosate is the most heavily used herbicide (a type of pesticide) in the world. Nearly 300 million pounds were applied in the U.S. in 2015, with much of the application in the Midwest. Scroll down to see a USGS map of glyphosate (Roundup) use in 2015 in the US. You can see that incredibly huge amounts of glyphosate are used in the midwest on farmland - greater than 88.6 pounds per square mile! (it's the dark brown areas on the map). Top crops it's used on are corn, soybeans, and canola, especially genetically modified Roundup Ready crops. It is also used as a dessicant right before harvest ("preharvest") on many crops. This is why crops have glyphosate residues on them, and why so many streams and lakes are contaminated (due to agricultural runoff). About 90% of corn and soybean crops grown in the United States are Roundup Ready, and then these grains are used in most processed foods. Note: glyphosate (Roundup) can not be used on organic crops.

The herbicide has been linked to a number of health problems, including cancer, birth defects, endocrine disruption, and reproductive problems. (Posts on glyphosate.)  There are currently hundreds of lawsuits from farmers and others claiming that Roundup gave them cancer.

...continue reading "Popular Weedkiller Found In Pregnant Women"

It looks like pesticide residues are increasing in our food. Not good, especially since we don't know what chronic low-levels of these residues do to us. And remember, we're exposed to mixtures of these residues daily, not just one at a time. The only way to reduce exposure to these pesticide residues, including the controversial and widely used pesticides 2,4-D and glyphosate, is by eating organic foods. [See all posts on PESTICIDES for more on their effects and concerns.] Excerpts from an article by journalist Carey Gillam in Environmental Health News:

Hold the plum pudding: US food sampling shows troubling pesticide residues

New data released recently by the Food and Drug Administration (FDA) shows a rise in the occurrence of pesticide residues detected in thousands of samples of commonly consumed foods. Documents obtained from the agency through Freedom of Information Act (FOIA) requests also show the government is bracing for more, with the use of at least one controversial weed killing chemical – the herbicide known as 2,4-D - expected to triple in the next year.

And buried deep within the FDA's latest annual pesticide residue report is data showing that a controversial insecticide called chlorpyrifos, which is marketed by Dow Chemical and is banned from household use due to known dangers, was the fourth-most prevalent pesticide found in foods out of 207 pesticides detected.

Overall, about 50 percent of domestic food and 43 percent of imported foods sampled showed pesticide residues in the FDA's testing for fiscal year 2015, which is the period covered in the new report. That is up from about 37 percent of domestic and 28 percent of imported foods found with residues in 2010, and up from 38.5 percent and 39 percent, respectively, found by FDA a decade earlier in 2005.

FDA sampling has been shrinking over the years, dropping about 25 percent from a decade ago from more than 7,900 samples to 5,989 samples tested in its latest report. The U.S. Department of Agriculture also does annual pesticide residue testing, but looks at more than 10,000 samples. The latest USDA residue report, which also was for the 2015 time period, found about 85 percent of samples contained pesticide residues.

Notably, samples of fruits and vegetables – considered healthy food choices – showed the highest frequency of pesticide residues in the new FDA report. Roughly 82 percent of domestic American fruits and 62 percent of domestic vegetables carried residues of weed killers, insecticides and other pesticides commonly used by farmers.

Looking at imported fruits and vegetables, the FDA found that roughly 51 percent of imported fruits and 47 percent of imported vegetables carried residues. Overall, the imported foods had more illegally high levels of pesticide residues than did domestic foods sampled. More than 9 percent of both imported fruits and vegetables were considered in violation of legal pesticide residue limits compared to only 2.2 percent of American-grown fruits and 3.8 percent of domestic vegetables. 

The Environmental Protection Agency sets legal limits, referred to as "maximum residue limits" (MRLs) for pesticide residues on foods. The FDA and USDA routinely assure consumers that if residues are below the established MRLs, they are both legal and safe. But many scientists and medical professionals disagree, saying regulatory methods are outdated and too dependent on input from the chemical industry players selling the pesticides. 

Separate from the FDA's published residue report, internal FDA documents show the agency working to get a handle on the residues of two widely used herbicides - glyphosate and 2,4-Dichlorophenoxyacetic acid (2,4-D)An internal memo dated in May of this year obtained through FOIA states that 2,4-D use is "expected to triple in the coming year" because of new genetically engineered crops designed to tolerate direct application of the herbicideNeither FDA nor USDA has routinely tested for glyphosate despite the fact it is the world's most widely used herbicide, and testing by academics, consumer groups and other countries has shown residues of the weed killer in food.

The prestigious medical journal The Lancet recently released a report by its Commission On Pollution and Health on the effects of various types of pollution (water, air, occupational, chemical, etc) on people and world economies - that is, the effect of pollution on "global health". The main finding: Diseases caused by pollution were responsible in 2015 for an estimated 9 million premature deaths -- 16 percent of all deaths worldwide. Pollution is now known to cause a wide variety of diseases and health problems, including asthma, cancer, neurodevelopmental disorders, and birth defects in children; and heart disease, stroke, chronic obstructive pulmonary disease, and cancer in adults. The list of health effects keeps increasing. [See all posts on pollution.]

The report states that certain types of pollution are increasing throughout the world - air, chemical, and soil pollution.They also discuss new and emerging pollutants (most of them chemical pollutants) whose effects on human health
are not yet fully understood, yet they are widely found in the environment and detected in most humans. The authors of the report even say: "At least some of these chemical pollutants appear to have potential to cause global epidemics of disease, disability, and death."

Chemical pollutants include: developmental neurotoxicants (e.g. pesticides, lead, mercury), endocrine disruptors (which have reproductive effects and can alter fertility), new classes of pesticides such as the neonicotinoids, chemical herbicides such as glyphosate (found in Roundup and the most commonly used pesticide in the world), nano-particles, and pharmaceutical wastes.

While most deaths from all sorts of pollution are currently occurring in poorer developing countries (e.g. China and India), we in the United States also have health effects and deaths from pollution - just not on the scale of those countries. Also, remember that winds carry pollutants globally - so that air pollution in China will cross the Pacific Ocean on the winds to the US.

Everyone agrees that taking action works - think of the success in banning lead, asbestos, and DDT in the United States. And amounts of six common air pollutants have been reduced by about 70% since passage of the Clean Air Act in 1970. We can thank laws, and organizations established due to environmental problems and crises in the past (e.g. the Environmental Protection Agency (EPA), Superfund legislation, Clean Water Act, Clean Air Act) for that.

From Science Daily: Pollution responsible for 16 percent of early deaths globally

Diseases caused by pollution were responsible in 2015 for an estimated 9 million premature deaths -- 16 percent of all deaths worldwide, according to a report. Simon Fraser University health sciences professor Bruce Lanphear is a Commissioner and author of The Lancet Commission on Pollution and Health that has released a report detailing the adverse effects of pollution on global health. ...."Pollution, which is at the root of many diseases and disorders that plague humankind, is entirely preventable." 

Commission findings include: - Pollution causes 16% of all deaths globally. Diseases caused by pollution were responsible in 2015 for an estimated 9 million premature deaths -- 16% of all deaths worldwide -- three times more deaths than AIDS, tuberculosis, and malaria combined; and fifteen times more than all wars and other forms of violence. It kills more people than smoking, hunger and natural disasters. In some countries, it accounts for one in four deaths. - Pollution disproportionately kills the poor and the vulnerable. Nearly 92% of pollution-related deaths occur in low- and middle-income countries. Within countries, pollution's toll is greatest in poor and marginalized communities. Children face the highest risks because small exposures to chemicals in utero and in early childhood can result in lifelong disease and, disability, premature death, as well as reduced learning and earning potential. - Pollution is closely tied to climate change and biodiversity. Fossil fuel combustion in higher-income countries and the burning of biomass in lower-income countries accounts for 85% of airborne particulate pollution. Major emitters of carbon dioxide are coal-fired power plants, chemical producers, mining operations, and vehicles.

A few excerpts (lead & pesticides) from the report in The Lancet: The Lancet Commission on pollution and health

Another example of the economic benefits of addressing pollution is seen in the consequences of removing lead from gasoline in the USA. This intervention began in 1975 and, within a decade, had reduced the mean blood concentration of lead in the population by more than 90%, almost eliminated childhood lead poisoning, and increased the cognitive capacity of all American children born since 1980 by 2–5 IQ points. This gain in intelligence has increased national economic productivity and will yield an economic benefit of US$200 billion (range $110 billion–300 billion) over the lifetimes of each annual cohort of children born since 1980, an aggregate benefit to-date of over $6 trillion.

Developmental neurotoxicants: Evidence is strong that widely used chemicals and pesticides have been responsible for injury to the brains of millions of children and have resulted in a global pandemic of neurodevelopmental toxicity. The manifestations of exposure to these chemicals during early development include loss of cognition, shortening of attention span, impairment of executive function, behavioural disorders, increased prevalence of attention deficit and hyperactivity disorder, learning disabilities, dyslexia, and autism.

Pesticides: More than 20,000 commercial pesticide products, including insecticides, herbicides, fungicides, and rodenticides are available on world markets. More than 1.1 billion pounds of these products are used in the USA each year and an estimated 5.2 billion pounds globally. ....The organophosphate insecticides are a large and widely used class of pesticides. Members of this class of chemicals are powerful developmental neurotoxicantsand prenatal exposures are associated with persistent deleterious effects on children’s cognitive and behavioural function and with long-term, potentially irreversible, changes to brain structure that are evident on MRI. 

Chemical herbicides account for nearly 40% of global pesticide use and applications are increasing. A major use is in production of genetically modified food crops engineered to be resistant to glyphosate (Roundup), the world’s most widely used herbicide. Glyphosate-resistant, so-called “Roundup Ready” crops, now account for more than 90% of all corn and soybeans planted in the USA, and their use is growing globally. Glyphosate is widely detected in air and water in agricultural areas, and glyphosate residues are detected in commonly consumed foods.

Once again the controversial herbicide (weed killer) glyphosate is in the news. Glyphosate is the active ingredient in Roundup (manufactured by Monsanto), and is the most commonly used pesticide in the world. Its use is increasing annually since the introduction of genetically modified crops that are tolerant of glyphosate being sprayed on them (Roundup Ready crops), and since the use of "preharvest" applications of Roundup. Over the years the US government has generally NOT been tracking how much glyphosate residues are in the foods we eat, but whenever a food is studied for glyphosate residues - they are found. (see all posts) Which means people are constantly ingesting low levels of glyphosate residues.

But what does that mean for humans? A  recently published study of 100 adults over the age of 50, residing in Southern California, and followed from 1993 to 2016, looked at detectable glyphosate and its metabolite aminomethylphosphonic acid (AMPA) residues in urine. They found that the number of people with detectable residues in urine, and also the actual levels found in the urine, really, really increased in the 23 years. The percentage of people who tested positive for glyphosate shot up by 500% in that time period - from 12 percent of the samples to 70 percent. WOW!

Are there health effects from constant ingestion in food from low levels of glyphosate? We don't know, because the studies on humans have not been done. There are a number of health concerns, including that it is a carcinogen (it has been classified as a "probable carcinogen" by some agencies), liver and kidney damage, that it acts as an antibiotic and disrupts the gut microbiome, and endocrine disruption. The researchers of this study are especially concerned about possible glyphosate health effects on the liver (liver disease), based on animal studies (animals exposed chronically to very low levels), and want to research this further.

However, the EPA keeps insisting it's safe (and to please ignore the conflicts and deals done with Monsanto in recent years), and actually raised the levels allowed in 2013 (due to corporate lobbying). Also, glyphosate is still not monitored by the Department of Agriculture's pesticide data program or the CDC's (Centers for Disease Control and Prevention) monitoring program of human exposure to environmental chemicals.

What can you do? Try to eat as many organic foods as possible because glyphosate (and Roundup) are not allowed to be used in organic farming. And don't use Roundup on your own property - because you can be exposed to it numerous ways (drinking and eating it in food, inhalation, through the skin).

From Medical Xpress: US study finds rise in human glyphosate levels

Levels of glyphosate, a controversial chemical found in herbicides, markedly increased in the bodies of a sample population over two decades, a study published Tuesday in a US medical journal said. The increase dated from the introduction of genetically-modified glyphosate-tolerant crops in the United States in 1994.

Researchers compared the levels of glyphosate in the urine of 100 people living in California. It covered a 23-year period starting from 1993, the year before the introduction of genetically-modified crops tolerant to Roundup. Glyphosate-containing Roundup, produced by US agro giant Monsanto, is one of the world's most widely-used weedkillers.

"Prior to the introduction of genetically modified foods, very few people had detectable levels of glyphosate," said Paul Mills, of the University of California at San Diego School of Medicine, the study's principal author. Among the study group, detectable amounts increased from an average of 0.20 micrograms per liter in 1993-1996 to an average of 0.45 micrograms in 2014-2016.

In July, California listed glyphosate as carcinogenic, and the World Health Organization International Agency for Research on Cancer called it "probably carcinogenic" in 2015. There are few human studies on the effects of glyphosate, but research on animals demonstrated that chronic exposure can have adverse effects, said Mills. Along with the European Commission's proposal on Tuesday, the European Parliament approved a non-binding resolution calling for the chemical to be banned by 2022.

Excerpts from Consumer Reports: We May Be Consuming More Glyphosate Than Ever Before

A 2016 report in the journal Environmental Health that looked at human and animal studies found a link between glyphosate exposure and a number of health problems, including liver and kidney damage, endocrine disruption, and an elevated risk of non-Hodgkin’s lymphoma. But a vast majority of those studies were done with animals.

In fact, very few human studies have been done on the health effects of glyphosate, and no federal agency monitors how much of the chemical makes it from the environment into our bodies. That lack of information makes it difficult to even begin to assess how much glyphosate is potentially harmful to humans and whether current exposure levels are above or below that mark.

Once again a study finds that pesticide exposure is linked to an adverse health effect - that pesticide exposure in the home during pregnancy and early childhood is linked to an elevated risk of brain tumor in the child. Other studies have also found that pesticides used in the home are associated with a higher risk of childhood cancers.

This is because pesticides do cross the placental barrier, as the study researchers point out: "There is evidence that pesticides cross the fetal-placental barrier since residues of some insecticides have been found in umbilical cord blood, neonatal hair, and meconium following maternal exposure during pregnancy." Also, the International Agency for Research on Cancer (IARC) has classified "more than twenty pesticide chemical compounds as potential human carcinogens".

The following are examples (but there are more) of other studies finding pesticide and childhood cancer links: A meta-analysis published in 2015 in Pediatrics by researchers at Harvard University found that children exposed to indoor insecticides (also herbicides) have a higher risk of certain childhood cancers, specifically leukemia, lymphomas, and brain tumors. A 2013 study published in Cancer Causes and Control found that professional pest control applications in the home within a year of conception and during pregnancy was associated with a higher risk of childhood brain tumors. A review of studies published in 2010 found that pesticide exposure during pregnancy and childhood increased the risk of childhood leukemia.

The good news is that there are alternatives to exposing fetuses and children to toxic pesticides at home - by using alternative ways of dealing with pests, such as least toxic Integrated Pest Management (IPM) or organic methods. That means doing other things (such as sealing or caulking holes, putting out traps and baits, vacuuming), a focus on least toxic methods and on prevention (here and here), rather than routinely applying toxic pesticides. If needed, least toxic pesticides include boric acid and vinegar. Other sources of pesticide exposure for pregnant women and children are foods and exposure in settings outside the home - perhaps even a friend's yard. By the way, pesticide exposure for everyone is linked to a higher risk of health problems, not just pregnant women and children.

From Science Daily: Pesticide use during pregnancy linked to increased risk of childhood brain tumors

Previous epidemiological studies have suggested that exposure to pesticides during pregnancy may have a possible role in the development of childhood brain tumors. In a new International Journal of Cancer analysis, researchers found a link between maternal residential pesticide use -- particularly insecticides -- and the risk of childhood brain tumorsThe analysis included 437 malignant childhood brain tumor cases and 3102 controls from two French studies. Pesticide use was associated with a 1.4-times increased risk of childhood brain tumors.

The investigators noted that many pesticide compounds are classified as probable carcinogens, and there is evidence that some insecticides can pass through the feto-placental barrier. "Although such retrospective studies cannot identify specific chemicals used or quantify the exposure, our findings add another reason to advise mothers to limit their exposure to pesticides around the time of pregnancy," said Nicolas Vidart d'Egurbide Bagazgoïtia, lead author of the study. [Original study.]

Two recent studies, both done in California, looked at different aspects of pesticide exposure. They highlight how people can be exposed to pesticides in the air they breathe, especially if they live in areas where pesticides are heavily applied (such as farms). But keep in mind that even in suburbia, every time a neighbor applies pesticides on the lawn or trees - there is drift, and so you are also exposed (e.g., breathing it, droplets on the skin).

The first study found that pregnant women with high pesticide exposure (living in areas near farms using pesticides) had increases in adverse birth outcomes (low birth weight, shorter pregnancy length, preterm birth, birth defects or abnormalities). No effects were seen with low pesticide exposure. But note that these results are what could be seen at birth - they do not include effects that can only be seen later, such as delayed development, learning disabilities, lower intelligence, asthma, autism - all effects found in some studies.

The other was a California Department of Pesticide Regulation (CDPR) 2016 report on air monitoring results (from 6 sites) of 32 chemicals (pesticides and breakdown products) in California. Some pesticides were not detected, some were only at trace amounts, and some were detected at higher amounts  - and the amounts fluctuated over the year and from site to site. [NOTE: They did not monitor for 2 widely used pesticides: glyphosate, which is in Roundup, and 2,4-D. Hmm...]. A Kern County high school monitoring site showed levels of the pesticide chlorpyrifos more than 18 times higher than EPA's "level of concern for pregnant women" - but yet these levels are considered OK for the general public.

Chlorpyrifos is "controversial" in that scientists (including EPA scientists), medical professionals, and farmworker organiztions asked that its use be banned due to its serious health effects on humans, but this year EPA chief Scott Pruitt refused to do so (he gave in to pesticide industry lobbying). The bottom lineWhat effect do the mixtures of pesticides (at chronic low levels) that we're exposed to have on us? Unknown. 

From Medical Xpress: Researchers unravel the negative effects of pesticide exposure on birth outcomes

Although common opinion holds that exposure to pesticides increases adverse birth outcomes, the existing body of scientific evidence is ambiguous..... A new study by researchers at UC Santa Barbara addresses the issue in a novel way—by analyzing birth outcomes in California's San Joaquin Valley. With more than one-third of the country's vegetables and two-thirds of its fruits and nuts produced there, the San Joaquin Valley, not surprisingly, is a heavy pesticide-use region. The UCSB team investigated the effect of exposure during pregnancy in this agriculturally dominated area and observed an increase in adverse outcomes accompanying very high levels of pesticide exposure

"For the majority of births, there is no statistically identifiable impact of pesticide exposure on birth outcome," said lead author Ashley Larsen, an assistant professor in UCSB's Bren School of Environmental Science & Management. "Yet mothers exposed to extreme levels of pesticides, defined here as the top 5 percent of the pesticide exposure distribution, experienced between 5 and 9 percent increases in the probability of adverse outcomes with an approximately 13-gram decrease in birth weight."

Using individual birth certificate records for more than 500,000 single births between 1997 and 2011, coupled with pesticide use data at a fine spatial and temporal scale, the scientists were able to determine if residential agricultural pesticide exposure during gestation—by trimester and by toxicity—influenced birth weight, gestational length or birth abnormalities.

They found negative effects of pesticide exposure for all birth outcomes—birth weight, low birth weight, gestational length, preterm birth, birth abnormalities—but only for mothers exposed to very high levels of pesticides—the top 5 percent of the exposure distribution in this sample.... Numerous chemicals are used daily in close proximity to residential areas, making it difficult to ascertain a specific responsible agent. As a result, in this study, the researchers looked at the combined results from all pesticides used in the region[Original study.]

Excerpts from Beyond Pesticides: Neurotoxic Pesticide Detected in Air at High Levels in California County

The California Department of Pesticide Regulation (CDPR) released its 2016 air monitoring data where it was revealed that chlorpyrifos air concentrations for a one-month period at the air monitoring site on the campus of Shafter High School in Kern County was 39.4 nanograms per cubic meter (ng/m3) – more than 18 times higher than EPA’s level of concern for pregnant women (2.1 ng/m3).  Shafter High School is some distance from fields in an area where chlorpyrifos use is not as high as in other parts of Kern County or elsewhere in California. 

High chlorpyrifos levels at a school means that children and unsuspecting teachers and parents, especially those that may be pregnant, are breathing in unusually high levels of chlorpyrifos. Children exposed to high levels of chlorpyrifos have developmental delays, attention problems, attention-deficit/hyperactivity disorder problems, and pervasive developmental disorders.