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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.

 News about the controversial pesticide Roundup and its active ingredient glyphosate just keep coming. Roundup is the most heavily used pesticide in the world, and it is used as a herbicide or weed-killer throughout the USA. Its use is rapidly rising, especially due to its use for preharvest applications on crops, and for genetically modified Roundup Ready crops. The chemical giant Monsanto (manufacturer of Roundup) insists that Roundup is safe for humans and the environment, but studies are indicating otherwise (see posts on Roundup). And yes, the pesticide and its residues are found wherever its presence is looked for. So one very important question is: If this heavily used pesticide is found in the foods we eat, and is around us (thus we have chronic low levels of exposure), what is it doing to us, if anything? 

This month the results of a study of 69 pregnant women receiving prenatal care at an Indiana obstetric practice was presented at a Children’s Environmental Health Network (CEHN) conference. The researchers reported that they found the presence of glyphosate and its breakdown products (aminomethylphosphonic acid or AMPA) in the urine of 91% of pregnant women. They found that higher levels of glyphosate were associated with lower than average birth weights and shorter pregnancy length (gestation age). Also, women living in rural areas had higher average glyphosate levels than women in urban/suburban regions. The researches suggested that it was because the rural women lived close to corn and soybean fields where glyphosate is heavily used.

The researchers also pointed out that this is especially worrisome because low birth weights and shortened pregnancy length (gestation) are seen as risk factors for many health and neurodevelopmental problems over the course of an individual’s life - lower cognitive abilities (including IQ), diabetes, heart disease, high blood pressure, and obesity. Of course the researchers plan to expand this research on more women.

But unfortunately US government agencies such as the FDA are not testing for the presence of glyphosate residues in foods (a major way we are exposed to glyphosate), even though they test for many other pesticides. So testing for the most heavily used pesticide in the world  in foods is deliberately not being done! It doesn't matter whether one thinks that Roundup (glyphosate) is harmful or not - we should know what foods this pesticide in the world appears in and at what levels. So far, whatever conventional foods are looked at, glyphosate residues are found. Even foods that one does not expect it in, such as honey. On the other hand, organic foods or crops are not allowed to use Roundup or glyphosate, so eating organic foods is the only way to avoid the pesticide. And of course, by not using Roundup or other glyphosate products on the property where you live.

The researchers and CEHN (Children’s Environmental Health Network) have put together a web-site documenting the increase in Roundup (glyphosate) use in the United States in the past few decades and why we should be concerned. There are many links at the thorough and well-researched site. If one looks at only a few pages, then look at the introduction page - The Project, the Birth Outcomes section, and the Biomonitoring Data page - which discusses "biomonitoring" to track levels of chemicals such as pesticides in human urine and blood, and why we should be concerned. They also discuss 2,4-D - another popular pesticide (herbicide or weed-killer), which is also used in many lawn "weed and feed" products. 2.4-D has serious health concerns, but its use is also rapidly increasing on farms due the increase in genetically modified crops (which allow it to be sprayed on crops without killing the crops).

Bottom line: We are being exposed to chronic low levels of pesticides in our environment and foods - and we really don't know what this is doing to us. We don't even know the extent of our exposures because it is not being measured. This is especially worrisome because our exposure to some of these pesticides is rapidly increasing.

From the investigative journalism site FERN: Researchers find glyphosate in pregnant women, worry about impact on infants

A team of scientists this week released early results of an ongoing study spotlighting concerns about the rising use of pesticides and reproductive risks to women and children. The researchers tested and tracked, over a period of two years, the presence of the common herbicide glyphosate in the urine of 69 expectant mothers in Indiana.

The team – led by Paul Winchester, medical director of the neonatal intensive care unit at the Franciscan St. Francis Health System and professor of clinical pediatrics at Riley Hospital for Children in Indianapolis, Ind. – found glyphosate residues in 91 percent of the women, and high levels of those residues appeared to correlate with shortened pregnancies and below-average birth weights adjusted for age. The findings alarmed the researchers because such babies are at increased risk of diabetes, heart disease, high blood pressure, and lower cognitive abilities. “Gestational age maximizes the size of your brain at birth, and any shortening is essentially a reduction of IQ points,” Winchester said in an interview with FERN’s Ag Insider. “It has not just health, but lifetime achievement implications.”

This is the first time that anyone has demonstrated glyphosate is present in pregnant women in the U.S., according to Winchester. However, the results were limited by a small sample size. He and his colleagues plan to submit their research to a peer-reviewed journal within the month and they hope to expand the study later this year. “The fact that we were able to find adverse effects on the small number of people we measured would imply a larger study is needed immediately to find out if this is prevalent everywhere,” Winchester says. “This is a critical piece of information that I think people should be concerned about.”

Glyphosate is the world’s most popular herbicide and the key ingredient in Monsanto’s Roundup weed killer. Globally, 9.4 million tons of glyphosate have been sprayed on crops, lawns, and gardens since the chemical was released on the market in 1974....Currently, concerns about the safety of glyphosate are at the center of a major national lawsuit. Monsanto is being sued by hundreds of U.S. consumers who say the company did not warn them, despite evidence, that the chemical can cause cancers such as non-Hodgkin lymphoma, a blood disease. A key piece of testimony in the suit is a 2015 International Agency for Research on Cancer (IARC) report stating that glyphosate is “probably carcinogenic to humans.” Monsanto contests the listing, citing rulings by the EPA, the European Chemicals Agency, and the European Food Safety Authority that did not find cancer risks.

Winchester has long studied the risks posed by agrochemicals, finding in a 2009 study that high levels of the farming chemical atrazine in water was associated with increased risk of genital birth defects in children. In the glyphosate study, Winchester and his colleagues considered whether water might again be the exposure route for the pregnant women they monitored. After testing water samples, the scientists concluded that it was not the source. They suspect diet may play a role. The Food and Drug Administration, however, recently suspended the testing of glyphosate residues in food, citing the need for improved validation methods.

Experts say the spread of weeds resistant to glyphosate in the Midwest is triggering intensification of herbicide use over longer periods of time. “Until this year, most herbicides in the Midwest were sprayed during a six-week window, but now heavy herbicide spray season will last at least four months, placing more women and children at heightened risk,” Phil Landrigan, dean for global health at Mount Sinai Medical School and a member of the research team, said in a statement. As a result, he and his colleagues predict the risk of reproductive problems and adverse birth outcomes will rise among women and children living in rural areas.

Another article on this research is from Carey Gillam for Huffington Post: Moms Exposed To Monsanto Weed Killer Means Bad Outcomes For Babies