Where Does the Arsenic in Rice, Mushrooms, and Wine Come From?

What happens when our crops are grown in soil contaminated with arsenic-based pesticides and arsenic drug-laced chicken manure?

When arsenic-containing drugs are fed to chickens, not only does the arsenic grow out into their feathers, which are then fed back to them as a slaughterhouse byproduct, but the arsenic can also get into their tissues and then into our tissues when we eat eggs or meat, a cycle depicted at the start of my video Where Does the Arsenic in Rice, Mushrooms, and Wine Come From?. This explains why national studies have found that those who eat more poultry have tended to have more arsenic flowing through their bodies. Why would the industry do that? In modern poultry farms, often called CAFOs for concentrated animal feeding operations, there can be 200,000 birds under one roof and the floors of these buildings become covered with feces. While this so-called factory farming decreases costs, it also increases the risk of disease. That’s where arsenic-containing drugs and other antibiotic feed additives can come in: to try to cut down the spread of disease in such an unnatural environment. If you’re feeling a little smug because you don’t eat chicken, what do you think happens to the poop?

As depicted at 1:17 in my video, from chicken manure, the arsenic from the drugs in the animal feed can get into our crops, into the air, and into the groundwater, and find its way into our bodies whether we eat meat or not. Yes, but how much arsenic are we really talking about? Well, we raise billions of chickens a year, and, if, historically, the vast majority were fed arsenic, then, if you do the math, we’re talking about dumping a half million pounds of arsenic into the environment every year—much of it onto our crops or shoveled directly into the mouths of other farm animals.

Most of the arsenic in chicken waste is water soluble, so, there are certainly concerns about it seeping into the groundwater. But, if it’s used as a fertilizer, what about our food? Studies on the levels of arsenic in the U.S. food supply dating back to the 1970s identified two foods, fish aside, with the highest levels—chicken and rice—both of which can accumulate arsenic in the same way. Deliver an arsenic-containing drug like roxarsone to chickens, and it ends up in their manure, which ends up in the soil, which ends up in our pilaf. “Rice is [now] the primary source of As [arsenic] exposure in a non seafood diet.”

I was surprised to learn that mushrooms are in the top-five food sources of arsenic, but then it made sense after I found out that poultry litter is commonly used as a starting material to grow mushrooms in the United States. As you can see at 2:58 in my video, over the years, the arsenic content in mushrooms has rivaled arsenic concentration in rice, though people tend to eat more rice than mushrooms on a daily basis. Arsenic levels in mushrooms seemed to be dipping starting about a decade ago, which was confirmed in a 2016 paper that looked at a dozen different types of mushrooms: plain white button mushrooms, cremini, portobello, shiitake, trumpet, oyster, nameko, maitake, alba clamshell, brown clamshell, and chanterelle. Now, mushrooms are only averaging about half the arsenic content as rice, as you can see at 3:37 in my video.

Just like some mushrooms have less arsenic than others, some rice has less. Rice grown in California has 40 percent less arsenic than rice grown in Arkansas, Louisiana, Mississippi, Missouri, and Texas. Why? Well, arsenic-based pesticides had been used for more than a century on millions of acres of cotton fields, a practice noted to be “dangerous” back in 1927. Arsenic pesticides are now effectively banned, so it’s not simply a matter of buying organic versus conventional rice because millions of pounds of arsenic had been laid down in the soil well before the rice was even planted.

The rice industry is well aware of this. There’s an arsenic-toxicity disorder in rice called “straighthead,” where rice planted in soil too heavily contaminated with arsenic doesn’t grow right. So, instead of choosing cleaner cropland, they just developed arsenic-resistant strains of rice. Now, lots of arsenic can build up in rice without the plant getting hurt. Can the same be said, however, for the rice consumer?

It’s the same story with wine. Arsenic pesticides were used, decade after decade, and even though they’ve since been banned, arsenic can still be sucked up from the soil, leading to “the pervasive presence of arsenic in [American] wine [that] can pose a potential health risk.” Curiously, the researchers sum up their article by saying that “chronic arsenic exposure is known to lower IQ in children,” but if kids are drinking that much wine, arsenic toxicity is probably the least of their worries.

Hold on. Chickens are being fed arsenic-based drugs? See Where Does the Arsenic in Chicken Come From? to find out more.


 I expect the arsenic-in-rice issue brought up a lot of questions, and giving you answers is exactly why I’m here! Check out:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Why Was Chicken the Primary Source of Arsenic Exposure in Children?

What was the National Chicken Council’s response to public health authorities calling for the industry to stop feeding arsenic-based drugs to poultry?

“Dietary practices influence our exposure to pesticides, toxic heavy metals, persistent organic pollutants, and industrial pollutants….A diet high in fish and other animal products, for example, results in greater exposure to persistent organic compounds and metals than does a plant-based diet because these compounds bioaccumulate up the food chain.” Researchers at UC Davis analyzed the diets of children and adults in California to see just how bad things have gotten.

Cancer benchmark levels were exceeded by all children—100 percent of children—for arsenic, the banned pesticides dieldrin and DDT, metabolite DDE, as well as dioxins, and not just by a little. As you can see at 0:51 in my video Where Does the Arsenic in Chicken Come From?, researchers found more than a hundred times the acceptable daily exposure for arsenic in preschoolers, school-aged children, parents, and older adults, about ten times the acceptable levels for various pesticides, and up to a thousand times the daily dose for dioxins. Where are all these toxins coming from?

The number-one source of dioxins in the diets of Californian preschoolers, kids, parents, and grandparents appears to be dairy for all age groups, followed by meat, and then white potatoes, refined grains, mushrooms, poultry, and fish.

These days, our DDT legacy is also mostly from dairy. Dieldrin was created as a safer alternative to DDT, but it was banned just two years later, in 1974, though it’s still found in our bodies, mostly thanks to dairy, meat, and, evidently, cucumbers.

Chlordane made it into the 1980s before being banned, though we’re still exposed through dairy (and cukes). Lead is — foodwise — also mostly from dairy, and mercury is not surprisingly mostly from tuna and other seafood. But the primary source of arsenic in children? Surprisingly, mostly from chicken. Why?

Let me tell you a tale of arsenic in chicken. Arsenic is “well known as a poison by anyone who reads mysteries or the history of the Borgias, and with its long and colourful history, arsenic is not something that people want in their food.” So, when a biostatistics student went to the USDA in 2000 in search of a project for his master’s degree, he decided to look into it. He found a startling difference: Arsenic levels in chicken were three times higher than in other meats. His veterinary colleagues weren’t at all surprised and explained that four different types of arsenic-containing antibiotic drugs are fed to poultry—and have been fed to them since 1944.

“While arsenic-based drugs had been fed to poultry since the 1940s, recognition of this source of exposure [for humans] only occurred after appropriate statistical analysis of the data”—that is, after this student churned through the data. It was published in 2004 and expanded upon in 2006. The National Chicken Council (NCC) was none too pleased, saying lots of foods are contaminated with arsenic. “By focusing specifically on chicken, IATP [the Institute for Agriculture and Trade Policy] makes it clear that it is producing a publicity-oriented document focused on the objective of forcing [chicken] producers to stop using these safe and effective products”—by which the NCC means these arsenic-containing drugs. In fact, the NCC admits to using them but says we don’t need to worry because chicken producers use organic arsenic, “not the inorganic form made infamous in ‘Arsenic and Old Lace.’” Okay, so we don’t need to worry—until, apparently, we cook it. When chicken is cooked, it appears that some of the arsenic drug in the meat turns into the ”Arsenic and Old Lace” variety. So, the Poison-Free Poultry Act of 2009 was introduced into Congress, flopped, and was followed by the subsequent introduction of the Poison-Free Poultry Act of 2011. Did the second attempt fare any better? No, legislators once again said pish posh to poison-poor poultry. So, in 2013, a coalition of nine organizations got together and sued the FDA, and by December 31, 2015, all arsenic-containing poultry drugs were withdrawn. As of 2016, arsenic is no longer to be fed to chickens. The bad news is that without giving birds the arsenic-containing drug roxarsone, chicken may lose some of its “appealing pink color.”

In the end, the poultry industry got away with exposing the American public to arsenic for 72 years. “It should be noted that the European Union has never approved drugs containing arsenic for animal consumption” in the first place, saying, Hmm, feed our animals arsenic? No thanks, nein danke, no grazie, non, merci.

Europe has also long since banned the “urgent threat to human health” posed by feeding farm animals millions of pounds of human antibiotics. As you can see at 5:30 in my video, feeding chickens en masse literally tons of drugs like tetracyclines and penicillins to fatten them faster is a problem that gets worse every year instead of better and dates back to 1951 when drug companies whipped out the ALL CAPS in advertisements,  promising “PROFITS…several times higher!”, a dangerous practice the poultry industry has gotten away with for 68 years…and counting.


If you don’t eat poultry and are feeling a little cocky, you may want to check out my 12-video series on arsenic in rice before you gloat too much:

Think feeding arsenic to chickens is weird? Check out Illegal Drugs in Chicken Feathers.

And for more on the critical public health threat posed by antibiotic overuse in animal agriculture, see:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

How to Treat Polycystic Ovary Syndrome (PCOS) with Diet

Given the role that oxidant free radicals are thought to play in aging and disease, one reason fruits and vegetables may be so good for us is that they contain antioxidant compounds. As you can see at 0:20 in my video Benefits of Marjoram for Polycystic Ovary Syndrome (PCOS), different vegetables and herbs have different antioxidant content. When making a salad, for example, spinach, arugula, or red leaf lettuce may provide twice the antioxidants as butterhead lettuce, and choosing purple cabbage over green, or red onions over white can also boost the salad’s antioxidant power.

Fresh herbs are so powerful that even a small amount may double or even quadruple the antioxidant power of the entire meal. For instance, as you can see at 0:50 in my video, the total antioxidants in a simple salad of lettuce and tomato jump up by adding just a tablespoon of lemon balm leaves or half a tablespoon of oregano or mint. Adding marjoram, thyme, or sage not only adds great flavor to the salad, but effectively quadruples the antioxidant content at the same time, and adding a little fresh garlic or ginger to the dressing ups the antioxidant power even more.

Herbs are so antioxidant-rich that researchers decided to see if they might be able to reduce the DNA-damaging effects of radiation. Radioactive iodine is sometimes given to people with overactive thyroid glands or thyroid cancer to destroy part of the gland or take care of any remaining tumor cells after surgery. For days after the isotope injection, patients become so radioactive they are advised not to kiss or sleep close to anyone, including their pets, and if they breathe on a phone, they’re advised to wipe it “carefully” or cover it “with an easily removed plastic bag.” Other recommendations include “avoid[ing] splatter of radioactive urine,” not going near your kids, and basically just staying away from others as much as possible.

The treatment can be very effective, but all that radiation exposure appears to increase the risk of developing new cancers later on. In order to prevent the DNA damage associated with this treatment, researchers tested the ability of oregano to protect chromosomes of human blood cells in vitro from exposure to radioactive iodine. As you can see at 2:25 in my video, at baseline, about 1 in 100 of our blood cells show evidence of chromosomal damage. If radioactive iodine is added, though, it’s more like 1 in 8. What happens if, in addition to the radiation, increasing amounts of oregano extract are added? Chromosome damage is reduced by as much 70 percent. Researchers concluded that oregano extract “significantly protects” against DNA damage induced by the radioactive iodine in white blood cells. This was all done outside the body, though, which the researchers justified by saying it wouldn’t be particularly ethical to irradiate people for experimental research. True, but millions of people have been irradiated for treatment, and researchers could have studied them or, at the very least, they could have just had people eat the oregano and then irradiate their blood in vitro to model the amount of oregano compounds that actually make it into the bloodstream.

Other in vitro studies on oregano are similarly unsatisfying. In a comparison of the effects of various spice extracts, including bay leaves, fennel, lavender, oregano, paprika, parsley, rosemary, and thyme, oregano beat out all but bay leaves in its ability to suppress cervical cancer cell growth in vitro while leaving normal cells alone. But people tend to use oregano orally—that is, they typically eat it—so the relevance of these results are not clear.

Similarly, marjoram, an herb closely related to oregano, can suppress the growth of individual breast cancer cells in a petri dish, as you can see at 3:53 in my video, and even effectively whole human breast tumors grown in chicken eggs, which is something I’ve never seen before. Are there any clinical trials on oregano-family herbs on actual people? The only such clinical, randomized, control study I could find was a study on how marjoram tea affects the hormonal profile of women with polycystic ovary syndrome (PCOS). The most common cause of female fertility problems, PCOS affects up to one in eight young women and is characterized by excessive male hormones, resulting in excess body or facial hair, menstrual irregularities, and cysts in one’s ovaries that show up on ultrasounds.

Evidently, traditional medicine practitioners reported marjoram tea was beneficial for PCOS, but it had never been put to the test…until now. Drinking two daily cups of marjoram tea versus a placebo tea for one month did seem to beneficially affect the subjects’ hormonal profiles, which seems to offer credence to the claims of the traditional medicine practitioners. However, the study didn’t last long enough to confirm that actual symptoms improved as well, which is really what we care about.

Is there anything that’s been shown to help? Well, reducing one’s intake of dietary glycotoxins may help prevent and treat the disease. Over the past 2 decades there has been increasing evidence supporting an important contribution from food-derived advanced glycation end products (AGEs)…[to] increased oxidative stress and inflammation, processes that play a major role in the causation of chronic diseases,” potentially including polycystic ovary syndrome (PCOS). Women with PCOS tend to have nearly twice the circulating AGE levels in their bloodstream, as you can see at 0:33 in my video Best Foods for Polycystic Ovary Syndrome (PCOS). 

PCOS may be the most common hormonal abnormality among young women in the United States and is a common cause of infertility, menstrual dysfunction, and excess facial and body hair. The prevalence of obesity is also higher in women with PCOS. Since the highest AGE levels are found in broiled, grilled, fried, and roasted foods of “mostly animal origin,” is it possible that this causal chain starts with a bad diet? For instance, maybe eating lots of fried chicken leads to obesity, which in turn leads to PCOS. In that case, perhaps what we eat is only indirectly related to PCOS through weight gain. No, because the same link between high AGE levels and PCOS was found in lean women as well.

“As chronic inflammation and increased oxidative stress have been incriminated in the pathophysiology [or disease process] of PCOS, the role of AGEs as inflammatory and oxidant mediators, may be linked with the metabolic and reproductive abnormalities of the syndrome.” Further, the buildup of AGE inside polycystic ovaries themselves suggests a potential role of AGEs contributing to the actual disease process, beyond just some of its consequences.

RAGE is highly expressed in ovarian tissues. The receptor in the body for these advanced glycation end products, the “R” in RAGE, is concentrated in the ovaries, which may be particularly sensitive to its effect. So, AGEs might indeed be contributing to the cause of PCOS and infertility.

Does this mean we should just cut down on AGE-rich foods, such as meat, cheese, and eggs? Or hey, why not come up with drugs that block AGE absorption? We know AGEs have been implicated in the development of many chronic diseases. Specifically, food-derived AGEs play an important role because diet is a major source of these pro-inflammatory AGEs. Indeed, cutting down on these dietary glycotoxins reduces the inflammatory response, but the “argument is often made that stewed chicken would be less tasty than fried chicken…” Why not have your KFC and eat it, too? Just take an AGE-absorption blocking drug every time you eat it to reduce the absorption of the toxins. What’s more, it actually lowers AGE blood levels. This oral absorbent drug, AST-120, is just a preparation of activated charcoal, like what’s used for drug overdoses and when people are poisoned. I’m sure if you took some ipecac with your KFC, your levels would go down, too.

There’s another way to reduce absorption of AGEs, and that’s by reducing your intake in the first place. It’s simple, safe, and feasible. The first step is to stop smoking. The glycotoxins in cigarette smoke may contribute to increased heart disease and cancer in smokers. Then, decrease your intake of high-AGE foods, increase your intake of foods that may help pull AGEs out of your system, like mushrooms, and eat foods high in antioxidants, like berries, herbs, and spices. “Dietary AGE intake can be easily decreased by simply changing the method of cooking from a high dry heat application to a low heat and high humidity…” In other words, move away from broiling, searing, and frying to more stewing, steaming, and boiling.

What we eat, however, may be more important than how we cook it. At 4:00 in my video, I include a table showing the amounts of AGEs in various foods. For instance, boiled chicken contains less than half the glycotoxins of roasted chicken, but even deep-fried potatoes have less than boiled meat. We can also eat foods raw, which doesn’t work as well as for blood pudding, but raw nuts and nut butters may contain about 30 times less glycotoxins than roasted, and we can avoid high-AGE processed foods, like puffed, shredded, and flaked breakfast cereals.

Why does it matter? Because study after study has shown that switching to a low-AGE diet can lower the inflammation within our bodies. Even just a single meal high in AGEs can profoundly impair our arterial function within just two hours of consumption. At 4:54 in my video, you can see the difference between a meal of fried or broiled chicken breast and veggies compared with steamed or boiled chicken breast and veggies. Same ingredients, just different cooking methods. Even a steamed or boiled chicken meal can still impair arterial function, but significantly less than fried or broiled.

“Interestingly, the amount of AGEs administered [to subjects] during the HAGE [high-AGE] intervention was similar to the average estimated daily intake by the general population,” who typically follow the standard American diet. This is why we can decrease inflammation in people by putting them on a low-AGE diet, yet an increase in inflammation is less apparent when subjects switch from their regular diet to one high in AGEs. Indeed, they were already eating a high-AGE diet with so many of these glycotoxins.

Do we have evidence that reducing AGE intake actually helps with PCOS? Yes. Within just two months, researchers found differences from subjects’ baseline diets switched to a high-AGE diet and then to a low-AGE diet, with parallel changes in insulin sensitivity, oxidative stress, and hormonal status, as seen at 5:54 in my video. The take-home learning? Those with PCOS may want to try a low-AGE diet, which, in the study, meant restricting meat to once a week and eating it only boiled, poached, stewed, or steamed, as well as cutting out fast-food-type fare and soda.

What if instead of eating steamed chicken, we ate no meat at all? Rather than measuring blood levels, which vary with each meal, we can measure the level of glycotoxins stuck in our body tissues over time with a high-tech device that measures the amount of light our skin gives off because AGEs are fluorescent. And, not surprisingly, this turns out to be a strong predictor of overall mortality. So, the lower our levels, the better. The “one factor that was consistently associated with reduced [skin fluorescence]: a vegetarian diet.” This “suggests that a vegetarian diet may reduce exposure to preformed dietary AGE…potentially reduc[ing] tissue AGE,” as well as chronic disease risk


What’s so great about antioxidants? See my videos:

Just how many antioxidants do we need? Check out:

For a few simple tips on how to quickly boost the antioxidant content of your food with herbs and spices, see my video Antioxidants in a Pinch.

I touched on the benefits of spearmint tea for PCOS in Enhancing Athletic Performance with Peppermint. Another sorely under-recognized gynecological issue is endometriosis, which I discuss in How to Treat Endometriosis with Seaweed.

Because of AGEs, I no longer toast nuts or buy roasted nut butters, which is disappointing because I really enjoy those flavors so much more than untoasted and unroasted nuts. But, as Dr. McDougall likes to say, nothing tastes as good as healthy feels. For more on why it’s important to minimize our exposure to these toxic compounds, see:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: