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An article points out what we should all be concerned with, but is being ignored - pesticide residues of glyphosate (found in Monsanto's Roundup) and 2,4-D in foods. Glyphosate is the most used pesticide in the world, and both glyphosate and 2,4-D pesticide residues in food are set to really increase with the introduction of genetically modified crops resistant to both pesticides (The farmers can spray the pesticides against weeds repeatedly and the crops won't die - they're resistant to the pesticides, so the crops and foods will contain pesticide residues.). Both pesticides are linked to a variety of health problems.

The FDA, under pressure, started analyzing some foods this year for glyphosate residues, but has already stopped due to "problems". When and if they resume is unknown. It is important to know that pesticide residues at varying levels have been found in many foods (here, here, and here). What this chronic low level exposure does to humans is unknown. The only way to avoid or minimize pesticide exposures is to eat organic foods (herehere, and here).

When reading the following excerpts, note that there are no standards for glyphosate residues in honey in the United States. Research by a FDA chemist and a chemist at the University of Iowa found residues of glyphosate at varying levels with a high of 653 parts per billion in one sample (in honey from Iowa) - which is more than 10 times the limit of 50 ppb allowed in the European Union. Other honey samples tested detected glyphosate residues from under 16 ppb to over 123 parts per billion ppb (in honey from Louisiana). I mention this because pesticide residues are an important issue - because we don't know what chronic exposure to mixtures of low levels of pesticides in foods does to us. To babies and children, to pregnant women, to the elderly, to all of us. The following article excerpts are by journalist Carey Gillam, from The Huffington Post:

FDA Suspends Testing for Glyphosate Residues in Food

Government testing for residues of an herbicide that has been linked to cancer has been put on hold, slowing the Food and Drug Administration’s first-ever endeavor to get a handle on just how much of the controversial chemical is making its way into U.S. foods. The FDA, the nation’s chief food safety regulator, launched what it calls a “special assignment” earlier this year to analyze certain foods for residues of the weed killer called glyphosate after the agency was criticized by the U.S. Government Accountability Office for failing to include glyphosate in annual testing programs that look for many less-used pesticides. Glyphosate is the most widely used herbicide in the world, and is the key ingredient in Monsanto Co.’s branded Roundup herbicide line.

Glyphosate is under particular scrutiny now after the World Health Organization’s cancer experts last year declared the chemical a probable human carcinogen. Several private groups and nonprofits have been doing their own testing, and have been finding glyphosate residues in varying levels in a range of foods, raising consumer concerns about the pesticide’s presence in the American diet.

The FDA’s residue testing for glyphosate was combined with a broader herbicides analysis program the FDA set in motion in February of this year. But the glyphosate testing has been particularly challenging for the FDA. The agency was finally forced to put the glyphosate residue testing part of the work plan on hold amid confusion, disagreement and difficulties ....FDA spokeswoman Megan McSeveney confirmed the testing suspension and said the agency is not sure when it will resume.....Alongside the testing for glyphosate, the FDA laboratories have also been analyzing foods for 2,4-D and other “acid herbicides,” documents obtained from the FDA show. The category of acid herbicides includes five of the top 10 active ingredients used in homes and gardens. Usage of 2,4-D is expected to triple in the coming year, according to the FDA.

McSeveney said glyphosate residues were only being analyzed in soy, corn, milk and eggs and the popcorn samples, while the other foods are being tested for residues of other herbicides. Earlier this year, one of the agency’s senior chemists also analyzed glyphosate residues in honey and oatmeal and reported his results to the agency. Some honey samples contained residue levels well over the limit allowed in the European Union. The United States has no legal tolerance for glyphosate in honey, though the Environmental Protection Agency (EPA) said recently it may set one because of the FDA findings. 

With the testing on hold, it is not clear when the agency might have final results on the glyphosate residue analysis. McSeveney said preliminary results showed no violations of legal tolerance levels allowed for glyphosate in the foods tested. She did not provide details on what, if any, levels of residue were found. Tolerance levels are set by the EPA for a variety of pesticides expected to be found in foods. When residue levels are detected above the tolerance levels, enforcement action can be taken against the food producers.

Though FDA annually tests domestic and imported foods for residues of other pesticides, it never tested for glyphosate before. It has not routinely tested for 2,4-D either, a fact also criticized by the GAO. The FDA testing for 2,4-D residues comes as the use of 2,4-D with food crops is expected to start rising due to the commercialization of new formulated herbicide products that combine glyphosate and 2,4-D. Safety questions have been raised about the combination. But the EPA gave a green light on Nov. 1 to a Dow AgroSciences’ herbicide combination of glyphosate and 2,4-D. The new products are intended to counter widespread weed resistance to glyphosate, and be used with new types of genetically engineered herbicide-tolerant crops.

A study by researchers showing troubling effects from certain pesticides (especially a class of fungicides) raises all sorts of questions: What is the long-term effect of chronic low doses of these fungicides in the foods we eat? How much of these chemicals are we getting exposed to? The Univ. of North Carolina researchers studied the effect of 294 chemicals (all common food-use pesticides or other environmental chemicals) on "mouse cortical neurons" (mouse brain cells). They found that one group of chemicals, which they referred to as "cluster 2", "mimics brain disorders" such as autism, advanced age, Alzheimer's, Parkinson's disease, and other neurodegenerative disorders. The chemicals (all pesticides, and mainly fungicides) causing these effects are: fenamidone, pyraclostrobin, famoxadone, trifloxystrobin, fenpyroximate, azoxystrobin, fluoxastrobin pyridaben and rotenone. Even though this study was done on mouse cortical neurons (in vitro), it is meaningful because of the similarities with human brain cells.

Very little is known about human exposure to these chemicals (how much is our exposure?) and their effects on humans, but the data suggest effects similar to that in neurological disorders. The researchers point out that many of the chemical residues in this cluster were found on conventionally raised foods, especially leafy green vegetables, and were detected at relatively high levels, especially pyraclostrobin. Most of these fungicides only came into use after 2000 and usage of these fungicides has been increasing in the U.S, with the exception of pyridaben (decreasing use) and rotenone (very low use). "These data suggest significant human exposure potential to many of the chemicals in cluster 2".

They point out that these fungicide residues have not been detected on organically produced foods (EPA and USDA data), which suggests a way to minimize exposure. None of these chemicals can be used by organic farmers in the U.S. Possible exposure is also from gardens and lawns (if used), contaminated water, and for farm workers in conventional agriculture. From Science Daily:

Could new class of fungicides play a role in autism, neurodegenerative diseases?

Scientists at the UNC School of Medicine have found a class of commonly used fungicides that produce gene expression changes similar to those in people with autism and neurodegenerative conditions, including Alzheimer's disease and Huntington's disease.

Mark Zylka, PhD, senior author of the study and associate professor of cell biology and physiology at UNC, and his team exposed mouse neurons to approximately 300 different chemicals.... "Based on RNA sequencing, we describe six groups of chemicals," Zylka said. "We found that chemicals within each group altered expression in a common manner. One of these groups of chemicals altered the levels of many of the same genes that are altered in the brains of people with autism or Alzheimer's disease." Chemicals in this group included the pesticides rotenone, pyridaben, and fenpyroximate, and a new class of fungicides that includes pyraclostrobin, trifloxystrobin, fenamidone, and famoxadone. Azoxystrobin, fluoxastrobin, and kresoxim-methyl are also in this fungicide class.

"We cannot say that these chemicals cause these conditions in people," Zylka cautioned. "Many additional studies will be needed to determine if any of these chemicals represent real risks to the human brain." Zylka, a member of the UNC Neuroscience Center, and his group found that these chemicals reduced the expression of genes involved in synaptic transmission -- the connections important for communication between neurons. If these genes are not expressed properly, then our brains cannot function normally. Also, these chemicals caused an elevated expression of genes associated with inflammation in the nervous system. This so-called neuroinflammation is commonly seen in autism and neurodegenerative conditions.

The researchers also found that these chemicals stimulated the production of free radicals -- particles that can damage the basic building blocks of cells and that have been implicated in a number of brain diseases. The chemicals also disrupted neuron microtubules. "Disrupting microtubules affects the function of synapses in mature neurons and can impair the movement of cells as the brain develops," Zylka said. "We know that deficits in neuron migration can lead to neurodevelopmental abnormalities. We have not yet evaluated whether these chemicals impair brain development in animal models or people."

Jeannie T. Lee, MD, PhD, professor of genetics at Harvard Medical School and Massachusetts General Hospital, who was not involved in this research, said, "This is a very important study that should serve as a wake-up call to regulatory agencies and the general medical community. The work is timely and has wide-ranging implications not only for diseases like autism, Parkinson's, and cancer, but also for the health of future generations. I suspect that a number of these chemicals will turn out to have effects on transgenerational inheritance."

Zylka's group also analyzed information from the U.S. Geological Survey, which monitors countywide pesticide usage, as well as the Food and Drug Administration and the U.S. Department of Agriculture, which test foodstuffs yearly for pesticide residues. Of the chemicals Zylka's team studied, only the usage of pyridaben has decreased since 2000. Rotenone use has remained the same since 2000. However, the use of all the fungicides in this group has increased dramatically over the past decade.

Indeed, a study from the Environmental Protection Agency found that pyraclostrobin is found on foods at levels that could potentially affect human biology, and another study linked pyraclostrobin usage to honeybee colony collapse disorder. The pesticide rotenone was previously implicated in Parkinson's disease through replicated animal experiments and through human epidemiological studies.....Previous work has also shown that a single dose of the fungicide trifloxystrobin reduced motor activity for several hours in female rats and for days in male rats. Disrupted motor function is a common symptom of Parkinson's disease and other neurological disorders. The related fungicide picoxystrobin impaired motor activity in rats at the lowest dose tested.

Zylka added, "The real tough question is: if you eat fruits, vegetables or cereals that contain these chemicals, do they get into your blood stream and at what concentration? That information doesn't exist." Also, given their presence on a variety of foodstuffs, might long term exposure to these chemicals -- even at low doses -- have a cumulative effect on the brain?

Zylka noted that conventionally grown leafy green vegetables such as lettuce, spinach, and kale have the highest levels of these fungicides. But due to each chemical's effectiveness at reducing fungal blights and rust, crop yields have increased and farmers are expanding their use of these chemicals to include many additional types of food crops.

Zylka's team hopes their research will encourage other scientists and regulatory agencies to take a closer look at these fungicides and follow up with epidemiological studies. "Virtually nothing is known about how these chemicals impact the developing or adult brain," Zylka said. "Yet these chemicals are being used at increasing levels on many of the foods we eat."

Applying fungicide to apple orchard. Credit: Univ. of Kentucky Agriculture Extension

The research finding that eating fruits and vegetables with high pesticide residues has a negative effect on sperm is disturbing. It wasn't the amount of fruits and vegetables eaten, it was eating fruits and vegetables with high levels of pesticide residues. Yes, the study does have some limitations (for example, a one time analysis, looked at men at a fertility clinic and not the general population), but...even with these limitations, the results are disturbing. Earlier studies of children showed that switching to an organic diet has almost immediate results of reducing pesticide residues in the body (OP Pesticides in Children’s Bodies: The Effects of a Conventional versus Organic Diet). So the advice here is try to increase the amounts of organic fruits and vegetables in the diet, especially those with high pesticide residue levels. Fruit or vegetables that were low in pesticide residues included peas, beans, grapefruit and onions. Those that had highest pesticide residues included peppers, spinach, strawberries, celery,blueberries, potatoes, peaches, plums, apples and pears. From Time:

A Diet High in Pesticides Is Linked to a Lower Sperm Count

The troubling link between pesticide exposure and fertility isn’t new; scientists have already established that people who work with pesticides tend to have lower fertility than people who don’t. But for the majority of us who don’t work with chemicals, diet is the biggest source of exposure, says Jorge Chavarro, MD, assistant professor of nutrition and epidemiology at Harvard School of Public Health and senior author of a new study published in the journal Human Reproduction.

Chavarro and his colleagues wanted to see if pesticide residues left on fruits and vegetables might have a similar effect on sperm—and their findings suggest that they did. Men who ate fruits and vegetables with a lot of pesticides had lower sperm counts and more oddly shaped sperm than those who had lower levels of dietary pesticide exposure.

Over an 18-month period, the researchers used data from the Environment and Reproductive Health (EARTH) study, including semen samples from 155 men who were being treated at a Boston fertility clinic and a food frequency questionnaire they completed. The researchers determined pesticide exposure by comparing the questionnaire answers with government data about produce pesticide levels in the USDA’s Pesticide Data Program.

The study didn’t tease out individual foods, but the researchers classified produce according to whether it had high or low-to-moderate levels of pesticides. Men who ate the most high-pesticide fruits and vegetables had a 49% lower total sperm count and 32% fewer sperm that were shaped normally, compared to men who ate the least amount of the high-pesticide produce.

Researchers gave each piece of produce a score based on its level of detectable pesticides, its level of pesticides that exceeded the tolerance level established by the U.S. Environmental Protection Agency, and whether the produce had three or more types of detectable pesticides. (The bigger the score, the more it hit all three measures.) Ranked from highest pesticide contamination to lowest, here were the top fruits and vegetables: Green, yellow and red peppers (6), Spinach (6), Strawberries (6), Celery (6), Blueberries (5), Potatoes (5), Peaches and plums (5), Apples or pears (5), Winter squash (4), Kale, mustard greens and chard greens (4), Grapes and raisins (4).

The team didn’t tease out associations with individual pesticides. But they believe that a mixture of pesticides—not just one particular pesticide—is responsible for the link. The strongest variable in their analysis were the proportion of fruits and vegetables consumed that use three or more pesticides. “The more pesticides are applied on any particular crop, that seems to be having a bigger impact,” Chavarro says...But for people who are concerned about their dietary exposure to pesticides, there are ways to lower it, he says, like eating organic and choosing produce not listed on the Environmental Working Group’s dirty dozen list.

From Science  Daily: Pesticides in fruit and vegetables linked to semen quality

Assistant Professor of Nutrition and Epidemiology at the Harvard T.H. Chan School of Public Health in Boston (USA), Jorge Chavarro, said: "These findings should not discourage the consumption of fruit and vegetables in general. In fact, we found that total intake of fruit and vegetables was completely unrelated to semen quality. This suggests that implementing strategies specifically targeted at avoiding pesticide residues, such as consuming organically-grown produce or avoiding produce known to have large amounts of residues, may be the way to go."

There were no differences seen between men in the four groups who consumed fruit and vegetables with low-to-moderate pesticide residues. In fact, there was a significant trend towards having a higher percentage of normally shaped sperm among men who consumed the most fruit and vegetables with low pesticide residues -- a relative increase of 37% from 5.7% to 7.8%...Note:Pesticide use varies from country to country, but in the USA those used on fruit and vegetables include Atrazine, Malathion, Chlorpyrifos and Carbendazim