Tom Philpott

The Drought Is Making California Sink—And Climate Change Makes the Drought Worse

| Thu Aug. 20, 2015 5:04 PM EDT
Between May 2014 and January 2015, parts of the Central Valley sank by as much as 13 inches.

The policymakers tasked with overseeing California's ever-stressed water supply got two pieces of rough news this week.

• The Central Valley is sinking—really fast. A new satellite analysis from NASA found that vast swaths of the state's most important growing region—a massive national supplier of vegetables, fruit, and nuts nationwide—is dropping as farmers tap underground aquifers to compensate for lack of water from the state's irrigation projects. Subsidence, as the phenomenon is known, damages crucial infrastructure like aqueducts, train tracks, bridges, roads, and flood-control structures. As a June 2015 Center for Investigate Reporting article showed, no state agency keeps track of the financial cost exacted by repairing the ravages of subsidence, but the price tag is likely already in the tens of millions of dollars. Some of the most severe subsidence, NASA found, occurred along the California Aqueduct, damaging a network of canals, pipelines, and tunnels that carries water collected from the Sierra Nevada Mountains to the southern Central Valley's farms. Subsidence also permanently reduces the underground aquifers' water storage capacity, NASA adds.

• Climate change is making the whole situation worse. In addition to an epochal drought—driven mainly by lack of winter snows in the Sierra Nevada mountains, the engine of California's water system—the state is also experiencing historically warm temperatures. And while climate change  isn't likely the main factor behind the precipitation drop, it does likely drive the current heat wave. This year, California and much of the western US have endured record-high temperatures, the National Oceanic and Atmospheric Administration reports.


Hot weather, of course, compounds the impact of droughts: It accelerates the loss of water stored in soil, vegetation, aqueducts, and reservoirs, a process known as evapotranspiration. In a just-published paper, researchers from Columbia University and the University of Idaho looked at temperature and precipitation data gathered between 1901 and 2014 and compared them to climate change models. They concluded that California's recent dearth of precipitation can be explained mainly by natural variability, but that that climate change-induced evapotranspiration has contributed dramatically to the drought's severity. Think of it like this: Lack of precipitation has severely limited new water coming into California, and climate change has hindered the landscape's ability to hold onto what little water is available. Over all, increased evapotranspiration is responsible for as much as 27 percent of the state's current water shortage, they calculated. Worse, going forward, "anthropogenic warming has substantially increased the overall likelihood of extreme California droughts," they concluded.

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New Monsanto Spray Kills Bugs by Messing With Their Genes

| Wed Aug. 19, 2015 5:05 AM EDT

In a fascinating long piece in MIT Technology Review, Antonio Regalado examines the genetically modified seed industry's latest blockbuster app in development—one that has nothing to do with seeds. Instead, it involves the industry's other bread-and-butter product: pesticide sprays. But we're not talking about the poisonous chemicals you convinced your dad to stop dousing the lawn with. The novel sprays in question are powered by a genetic technology called RNA interference, which promises to kill specific insects and weeds by silencing genes crucial to their survival, while leaving nontarget species unscathed.

RNAi, as it's known, is an emerging science; the two US researchers who discovered it brought home a Nobel Prize in 2006. Regalado describes the process like this:

The cells of plants and animals carry their instructions in the form of DNA. To make a protein, the sequence of genetic letters in each gene gets copied into matching strands of RNA, which then float out of the nucleus to guide the protein-making machinery of the cell. RNA interference, or gene silencing, is a way to destroy specific RNA messages so that a particular protein is not made.

If you can nix RNA messages that exist to generate crucial genes, you've got yourself an effective bug or weed killer. And GMO seed and pesticide behemoth Monsanto thinks it has just that. Robb Fraley, the company's chief technology officer and a pioneer in creating GM seeds, told Regalado that within a few years, RNA sprays would "open up a whole new way to use biotechnology" that "doesn't have the same stigma, the same intensive regulatory studies and cost that we would normally associate with GMOs." Fraley described the novel technology as "incredible" and "breathtaking."

A Monsanto exec describes the novel technology as "incredible" and "breathtaking."

It's not hard to see why the veteran agrichemical and biotech exec is so amped for something new to load into a crop duster. Monsanto's GM herbicide-resistant and insecticidal traits still dominate the highly lucrative US corn, soybean, and cotton seed markets, but these cash-cow products are victims of their own success, so widely used that weeds and pests are rapidly developing resistance to them. The company's flagship herbicide, Roundup, still generates about $5 billion in sales annually, but it went off-patent years ago, and it was recently declared a "probable carcinogen" by the World Health Organization—a finding Monsanto disputes.

Such concerns are widely seen as the reason Monsanto is so hotly pursuing a takeover of its rival, Syngenta, which focuses much more on pesticides than novel seeds. Syngenta, too, is developing RNAi technology, reports Regalado—back in 2012, it spent $523 million to buy Devgen, a company that had been developing the novel sprays.

However, there's no reason to assume crop dusters will be strafing farm fields with gene-silencing sprays anytime soon. As Regalado notes, they're very little studied outside of corporate labs. "So far, only a few scientific publications even mention the idea of RNA sprays," he writes. "That makes it hard to judge companies' claims."

The first obstacle is technological—the problem of "how to get a large, electrically charged molecule like RNA to move through a plant's waxy cuticle and into its cells," Regalado writes. That's crucial, because the technology works like this: A targeted bug—the one drawing attention now from Monsanto is the Colorado potato beetle—chomps on a leaf that's been sprayed by RNA solution and then, fatally, gets critical genes turned off. To make that happen, you have to get the RNA material into the leaf.

The most promising solution so far is to "encapsulate the RNA in synthetic nanoparticles called lipidoids—greasy blobs with specialized chemical tails," Regalado reports. "The idea is to slip them into a plant, where the coating will dissolve, releasing the RNA."

The EPA's current methods of evaluating new pesticides, which were designed to vet chemicals, might not apply to gene-altering sprays.

This nanotech booster to Monsanto's new bug killer won't likely raise red flags from government overseers. As I've shown before, both nanotechnology and adjuvants—the compounds mixed with pesticides to help them break into plants—are lightly regulated.

However, the RNAi compound itself will have to be reviewed by the Environmental Protection Agency, which vets new pesticides before they reach farm fields. Early indications suggest the going will be bumpy. Last year, the EPA convened a scientific advisory panel to assess the human health and ecological risks posed by emerging RNAi crop technologies.

The panel concluded there's "no convincing evidence" that RNAi material poses a threat to humans or other animals—the digestive process likely destroys it before it can do harm. But for nontarget insects in the field, they concluded, it's a different story. The technology's boosters claim the technology can target particular pests and leave everything else in the ecosystem alone. The independent scientists on the EPA panel were not convinced. They noted "uncertainties in the potential modes of action in non-target species, potential for chronic and sublethal effects, and potential unintended consequences in the various life stages of non-target organisms." As a result, they found  "sufficient justification to question" whether the EPA's current methods of evaluating new pesticides, which were designed to vet chemicals, apply to these gene-altering treatments.

And the technology is so novel that figuring out what those tests should be will be hard— it "cannot be done without a better understanding" of exactly how the technology works, the panel concluded. US Department of Agriculture entomologists Jonathan Lundgren and Jian Duan raised similar concerns in a 2013 paper.

"This is surprisingly reminiscent of Monsanto's assurances in the '90s that weeds would be very unlikely to develop resistance" to Roundup, said one critic of the new technology.

One particular concern for the EPA panel was the amount of time RNAi material stays intact after it's sprayed. Monsanto says not to worry, because "when the company doused dirt with RNA, it degraded and was undetectable after 48 hours," Regalado reports. But he adds that Monsanto "wants to develop longer-lasting formulations," noting that another RNAi spray it's developing for trees was shown to persist for months. "What's more," Regalado notes, "Monsanto's own discoveries have underscored the surprising ways in which double-stranded RNA can move between species"—not exactly a comforting aspect of a technology Monsanto hopes to see widely used on farm fields.

A Monsanto geneticist told Regalado that the company hopes to get its first RNAi spray, one targeting potato beetles, into the market by 2020. The company is also working on an RNAi product to add to its failing Roundup herbicide—one it hopes can turn off the resistant genes in the superweeds now rampant on US farm fields. But that's well behind the potato beetle product in Monsanto's development timeline, a company spokeswoman told me.

In addition to its sprays, Monsanto has an RNAi-enhanced corn crop in the pipeline: a corn type engineered to contain RNA that was designed to kill a common pest called the rootworm. It's "currently pending approval from the EPA," the Monsanto spokeswoman said. "We are planning for a full commercial launch by the end of the decade, pending key regulatory approvals."

Doug Gurian-Sherman, a plant pathologist by training who covers biotechnology for the Center for Food Safety, echoed the EPA panel's concerns."These are very complex biological systems, and their interactions evolve, and are not static," he said. "So it is really impossible to predict all the things that could go wrong. That does not mean we should be paranoid about them, but we should be at least reasonably cautious and skeptical about claims of both safety and efficacy, since there is little experience or research to rely on."

He also questioned Monsanto's claim, reported by Regalado, that insects won't likely develop resistance to the RNAi treatments, as they have to most chemical treatments in the past. "This is surprisingly reminiscent of Monsanto's assurances in the '90s that weeds would be very unlikely to develop resistance to the glyphosate [Roundup] herbicide…and now we have an epidemic of glyphosate resistant weeds," Gurian-Sherman said. 

How the Midwest's Corn Farms Are Cooking the Planet

| Wed Aug. 12, 2015 5:00 AM EDT

I've been thinking a lot recently about how fertilizer from the Midwest's big corn farms seeps into streams and causes trouble—fouling water supplies in Columbus, Toledo, Des Moines, and 60 other towns in Iowa, and generating a Connecticut-sized dead zone at the heart of the continental United States' most productive fishery, the Gulf of Mexico. (Farms in the region also plant soybeans, but corn is by far the bigger fertilizer user.) But there's another way the Corn Belt's fertilizer habit damages a common resource: by releasing nitrous oxide (N2O), a greenhouse gas with nearly 300 times the heat-trapping power of carbon dioxide.

Scientists had been undercounting nitrous oxide emission in the Corn Belt by about 25 gigagrams annually—the equivalent of about 1.6 million cars on the road.

It turns out that the region's farms are likely generating much more nitrous oxide than scientists previously thought, according to a new peer-reviewed study by a team of researchers from the University of Minnesota, Yale, and the US Department of Agriculture.

Scientists had assumed that most nitrous oxide emissions from farming occurred at the soil level—some of the nitrogen fertilizer applied onto farmland vaporizes into nitrous oxide. But as citizens of Des Moines, Columbus, and the Gulf coast know well, nitrogen fertilizer doesn't stay in soil; a portion of it leaches into streams. And some of that escaped nitrogen, too, transforms into nitrous oxide.

To measure how much, the team, led by University of Minnesota researcher Pete Turner measured N2O emissions at 19 streams over a two-year period in ag-intensive southeastern Minnesota. They found that standard greenhouse gas emission measures, such as those used by the Intergovernmental Panel on Climate Change (IPCC), have been undercounting these "riverine" emission sources by a factor of nine; and overall N2O emissions from the area are underestimated by about 40 percent.

While they only took measurements in one small part of the US Midwest, the researchers write that other regions of the globe have similar conditions: large swaths of land dominated by fertilizer-intensive farming. Such areas include the rest of the US Corn Belt plus parts of China, Europe, and India. These industrial-scale farming regions, which together make up a landmass of about 580 million acres (nearly six times the size of California), are the globe's most potent sources of nitrous oxide, and we're likely drastically undercounting their total emissions, the study suggests.

Altogether, the paper estimates, typical assessments undercount nitrous oxide emission in the Corn Belt by about 25 gigagrams annually. According to my back-of-the-envelope calculation, that's the equivalent of about 1.6 million cars on the road over a year (assuming that 1 gram of nitrous oxide has the heat-trapping power of about 300 grams of carbon dioxide, and that the average passenger car burns through 4.75 metric tons of CO2 equivalent each year).

So efforts to rein in fertilizer runoff in the Corn Belt aren't just about cleaner water and lower filtration bills for the area's urban residents, or a more vibrant Gulf of Mexico fishery. They're also about stabilizing the climate. Back in 2013, I profiled Ohio farmer David Brandt, who has innovated a method for churning out bumper harvests using much less fertilizer, leading to much less runoff.

Death Rates From Alzheimer's and Other Cognitive Diseases Are Spiking

| Tue Aug. 11, 2015 5:00 AM EDT

The good news from this new mortality study is that US cancer and cardiovascular death rates have dropped over the past quarter-century. The bad news is that death rates from neurological diseases like Alzheimer's have soared—and Americans are much likelier to die from these diseases than their peers in most other developed countries.

To get their results, researchers from Bournemouth University in the United Kingdom looked at World Health Organization mortality statistics for 21 developed nations, comparing the 1989–91 period with the 2008–10 time frame.

For adults between the ages of 55 and 74, overall neurological death rates barely budged, rising 2 percent for men and 1 percent for women. But here in the United States, things got dramatically worse—death rates from dementia and other brain-related illnesses like Parkinson's disease and motor neuron disease spiked, jumping 82 percent for men and 48 percent for women. American men and women in this age group now have the second-highest neurological death rates in the developed world, behind Finland. In the earlier period, they ranked 17th and 11th, respectively.

For the elderly (aged 75 and up), the situation is even more dire. Overall, the neuro-related death rate jumped 114 percent for men and 185 percent for women. Here in the United States, elderly death rates from neurological causes leapt more than twofold (368 percent) for men and more than fivefold (663 percent) for women. Neurological causes now kill more elderly American women than cancer does.

Over the same time frame, death rates from cancer and cardiovascular disease dropped, both in the developed world overall and in the United States in particular. For 55- to 74-year-olds, male cancer death rates fell 20 percent overall, and US rates dropped 36 percent. Women in that age group showed a 16 percent reduction in cancer deaths throughout the developed world and an 18 percent reduction in the United States. Similar trends held true for heart-related diseases.

When you look only at Alzheimer's isolated from other neurological diseases, you'll also see a relative spike in deaths, as this chart from a 2015 report by the US-based Alzheimer's Association shows.

Alzheimer's Association

What gives? Why are so many Americans so much more at risking of dying of neurological diseases like Alzheimer's, even as other threats recede? And in the developed world as a whole, why are neurological-related death rates rising for people over the age of 75?

One obvious factor is that medical science has come up with all sorts of treatments to prolong the lives of people with cancer and cardiovascular conditions, while treatments for Alzheimer's have proven elusive. It could be simply that Alzheimer's and other neurological diseases are "diseases of the elderly"—that our brains are doomed to decline past a certain age, and more and more people are surviving cancer and heart disease only to "develop diseases that they would not have lived long enough to have acquired in previous times," as the authors of the UK study put it. But that probably doesn’t fully explain the findings, particularly since some countries, like the United States, have fared so much worse than others.

The study's authors don't speculate much on what's driving the trends they identified; they suggest that lifestyle factors might play a role. Heather Snyder, director of medical and scientific relations at the Alzheimer's Association, told me that there are significant but still-inconclusive links between cognitive decline and diet-related maladies like obesity and diabetes. A 2015 paper she co-authored delivers a broad state-of-the-science view on the relationship. Here's a summary.

"Summary of the evidence on modifiable risk factors for cognitive decline and dementia: A population-based perspective," Baumgartan, et al.

Indeed, there's mounting evidence that high-sugar diets contribute to cognitive decline, a trend I wrote about here. There's also compelling evidence that air pollution might be a trigger of neurodegenerative diseases, as Aaron Reuben's recent Mother Jones blockbuster shows.

Coca-Cola to World: Don't Stop Swilling Sugary Drinks, Just Exercise!

| Mon Aug. 10, 2015 5:32 PM EDT

Stunningly, one-third of American adults have a condition called metabolic syndrome, defined as "a cluster of major cardiovascular risk factors related to overweight/obesity and insulin resistance." People with metabolic syndrome are twice as likely to develop heart disease as people without it, and five times as likely to develop full-blown type II diabetes. Meanwhile, a growing body of research links insulin resistance with Alzheimer's and other forms of cognitive decline.

There's a solid consensus that two things need to happen to reverse this budding calamity: People need to eat better—less hyperprocessed, sugar-laden fare—and exercise more.

Now, if you were in the business of selling sweet beverages—ones that contain about nine teaspoons of sugar per 12-ounce serving—you'd have an interest in suggesting that maybe diet's not that big of an issue, after all. Instead of cutting down on soda, why not just take an extra walk around the block?

According to this New York Times exposé, Coca-Cola, the globe's biggest purveyor of sugary drinks, invested $1.5 million last year to launch the Global Energy Balance Network, which, the Times reports, "promotes the argument that weight-conscious Americans are overly fixated on how much they eat and drink while not paying enough attention to exercise."

The beverage maker has also invested "close to $4 million in funding for various projects spearheaded by two prominent US health academics who serve on GEBN's executive committee, the Times adds. One of them, University of South Carolina health professor Steven Blair, is featured in the above video insisting that "most of the focus in the popular media and in the scientific press is, 'Oh they're eating too much, eating too much, eating too much'—blaming fast food, blaming sugary drinks, and so on [for rising obesity rates]… And there's really virtually no compelling evidence that that, in fact, is the cause."

Meanwhile, the World Health Organization recommends holding added sugar consumption to about 25 grams (six teaspoons) per day—meaning a single Coke (nine teaspoons of sugar) will take you 50 percent over its daily recommendation. My colleague Maddie Oatman has a great piece on just how easy it is to catapult over the six-teaspoon limit in the sugar-happy US food environment.

Now, Coke's high-dollar drumbeating about how sugary drinks don't matter much may be nefarious, but it’s also sort of desperate. People are wising up—soda sales have fallen for 10 straight years.

The Big-Ag-Fueled Algae Bloom That Won't Leave Toledo's Water Supply Alone

| Wed Aug. 5, 2015 5:05 AM EDT
A vast Lake Erie algae bloom returns, captured by a NASA satelite on July 28.

The citizens of Toledo, Ohio, have embarked upon their new summer ritual: stocking up on bottled water. For the second straight year, an enormous algae bloom has settled upon Lake Erie, generating nasty toxins right where the city of 400,000 draws its tap water.

It's a kind of throwback to Toledo's postwar heyday, when the Rust Belt's booming factories deposited phosphorus-laced wastewater into streams that made their way into Lake Erie, feeding algae growths that rival today's in size. But after the decline of heavy industry and the advent of the Clean Water Act, there's a new main source of algae-feeding phosphorus into the beleaguered lake: fertilizer runoff from industrial-scale corn and soybean farms. (Background here.) 

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A Federal Judge Just Struck Down Idaho’s Law Against Secretly Videotaping Animal Abuse on Farms

| Tue Aug. 4, 2015 5:34 PM EDT

Captured by undercover investigators and released in 2012, the above video depicts a disturbing scene inside a large Idaho dairy facility. We see workers committing various acts of violence against cows: kicking and punching them, beating them with rods, twisting their tails, and, most graphically, wrapping a chain around the neck of a downed cow and dragging it with a tractor. The exposed dairy promptly fired five workers in the aftermath, but behind the scenes, Idaho's $6.6 billion dairy industry quietly began working with its friends in the state legislature on a different response, according to US District Court Judge B. Lynn Winmill.

In a decision released Monday, Winmill wrote that the Idaho Dairymen's Association "responded to the negative publicity by drafting and sponsoring" a bill that criminalizes the "types of undercover investigations that exposed the [violent] activities." Known as ag gag legislation—check out Ted Genoways' must-read Mother Jones piece on the phenomenon—it sailed through the Idaho Legislature and became a law in 2014.

Winmill declared the law unconstitutional in his decision, stating that its only purpose is to "limit and punish those who speak out on topics relating to the agricultural industry, striking at the heart of important First Amendment values." Moreover, the judge ruled, the law violates the Equal Protection Clause of the 14th Amendment, "as well as preemption claims under three different federal statutes." Ouch.

According to Food Safety News, seven other states have similar ag gag laws on the books. "This ruling is so clear, so definitive, so sweeping," Leslie Brueckner, senior attorney for Public Justice (co-counsel for the plaintiffs in the case), told ThinkProgress. "We couldn't ask for a better building block in terms of striking these laws down in other states."

Fumes From Iowa Hog-Manure Pit Kill Father and Son

| Thu Jul. 30, 2015 5:56 PM EDT
Hogs in a concentrated animal feeding operation (CAFO). Note the slatted floor.

Here's another reason why Americans should think twice about how the United States is emerging as the globe's hog farm: concentrating thousands of hogs in one place means concentrating huge amounts of their shit, too; and that shit puts off gases that are so noxious that they can kill people who work near them. Think I'm exaggerating? Get this, from the Des Moines Register:

A father and his son who were so close that they were “like glue” were killed Saturday by noxious fumes from a northwest Iowa hog manure pit—the second father and son in the Midwest to die of poisonous manure pit gases this month.

These large, indoor facilities confine hogs above their own waste on a slatted floor—the waste falls through the slats and collects in a pit below. An incredibly putrid aroma—I've smelled it—shrouds these facilities. The air contains hydrogen sulfide, methane, ammonia, carbon dioxide, and volatile organic compounds. Hogs can live above these poison-gas cesspools because giant fans keep the air moving. But when something goes wrong beneath the slats, workers have to venture into places where there is no effective ventilation. And that's what happened on this Iowa hog farm, to heartbreaking effect.

The two were repairing a pump at a hog confinement when a piece of equipment they were using fell into the manure pit, Wempen [a relative] said. Austin Opheim went into the pit first to retrieve the equipment, and his father followed him after realizing his son had been overcome by gases, Wempen said. ...  “(Gene) was carrying Austin on his back and bringing him up and he got almost to the top and he got overcome, and down they went,” she said.

An eerily similar father-son tragedy occurred in Wisconsin earlier in July.

Such disasters can usually be averted by donning proper breathing equipment when venturing beneath the slats. But in recent years, Midwestern hog facilities have been beset by a mysterious foam that settles at the surface of manure pits, which creates a buildup of volatile gases that that has caused many explosions. Back in June, two workers at a Minnesota hog farm died in a fire that erupted after they had been cleaning the slats of an empty hog facility—apparently the result of "power-washing activities bursting the foam bubbles in the manure pit" below. And last year, reports the trade journal Pork Network, a "similar fire in Iowa severely burned Leon Sheets, a past president of the Iowa Pork Producers Association, as he power-washed one of his hog barns."

Watch What It's Like to Live Amidst Industrial Hog Farms

| Wed Jul. 29, 2015 12:33 PM EDT

As I showed recently, the United States is emerging as the world's hog farm—the country where massive foreign meat companies like Brazil's JBS and China's WH Group (formerly Shuanghui) alight when they want to take advantage of rising global demand for pork. (If JBS's recent deal to buy Cargill's US hog operations goes through, JBS and WH Group together will slaughter 45 percent of hogs grown in the United States.)

A recent piece by Lily Kuo in Quartz (companion video above) documents what our status as the world's source of cheap pork means for the people who live in industrial-hog country. It focuses on Duplin County in eastern North Carolina, which houses "about 530 hog operations with capacity for over 2 million pigs ….one of the highest concentrations of large, tightly-controlled indoor hog operations, also known as CAFOs (concentrated animal feeding operations) in the world." In Duplin, "hogs outnumber humans almost 32 to 1," Kuo reports. And that means living amid lots and lots of pig shit—the county's hog facilities generate twice the annual waste of the entire population of New York City.

As I've shown before, the hog industry doesn't build wealth in the communities where it operates—the opposite, in fact. "Almost a quarter of the population lives below the poverty line, making Duplin County one of the poorest counties in North Carolina," Kuo writes. "It is also disproportionately black and Hispanic compared to the rest of the state."

Scientists Say Supposedly Miraculous Ingredients in Weed Killers Don't Actually Work

| Wed Jul. 29, 2015 5:00 AM EDT

Before pesticides go from the laboratory to the farm field, they have to first be vetted by the Environmental Protection Agency. But they're commonly mixed—sometimes by the pesticide manufacturers, sometimes by the farmers themselves—with substances called adjuvants that boost their effectiveness (to spread more evenly on a plant's leaf in the case of insecticides, or to penetrate a plant's outer layer, allowing herbicides to effectively kill weeds). Despite their ubiquity, adjuvants aren't vetted by the EPA at all; they're considered "inert" ingredients.

Despite their ubiquity, adjuvants aren't vetted by the EPA at all; they're considered "inert" ingredients.

I first wrote about them last year, when adjuvants mixed with fungicides came under suspicion of triggering a large bee die-off during California's almond bloom. Recently, an eye-popping article by Purdue weed scientists in the trade journal Ag Professional brought them to my attention again. The piece illustrates the unregulated, Wild West nature of these additives.

In the article, the authors note that two companies are hotly promoting adjuvant products as a kind of miracle cure for the ever-increasing scourge of herbicide-resistant weeds. That's a bold claim, given that resistant weeds now plague more than 60 million acres of farmland.

Odder still, both companies attribute their products' effectiveness to nanotechnology, a controversial, lightly regulated engineering tool that leverages the fact that when you break common substances into tiny particles, they behave in radically different ways than they do at normal sizes. Nanoparticles are so tiny, their size is measured in nanometers—a billionth of a meter. (A human hair is about 80,000 nanometers thick; nanoparticles typically measure in at less than 100 nanometers.)

An adjuvant called ChemXcel, from a Minnesota-based company called C&R Enterprises, claims to "kill herbicide-resistant weeds" when mixed with common herbicides like glyphosate. It works its magic through "patented, proprietary nano-drivers" that "alter the glyphosate chemistry" by "coating the individual DNA gene-sequencing molecules internally," the company claims.

Then there's NanoRevolution 2.0, marketed by a company called Max Systems. When goosed with a bit of NanoRevolution 2.0, the company states, "the herbicide 'piggybacks' onto the nano particles as they penetrate the leaf structure, carrying the herbicide directly to the root system for a faster enhanced plant absorption of herbicides even on hard-to-control weeds."

Taken aback by the claims and the use of nanotech, I contacted the EPA to see what, if anything, the agency had to say. "While we are not familiar with those particular products, EPA has jurisdiction over substances that meet the definition of pesticides, that is, claims are made for them that they kill, repel, prevent, or otherwise control pests," an Environmental Protection Agency spokesperson wrote in an email. "As long as pesticide adjuvant products don’t make pesticidal claims, they are not pesticides and the components of adjuvants are therefore not pesticide ingredients (either active or inert)"—and thus not subject to EPA vetting. Manufacturers aren't even required to list ingredients in adjuvants.

Here, for example, is Max Systems describes the ingredients of NanoRevolution 2.0:

Purdue weed scientist Bill Johnson, who co-authored the Ag Professional piece, says he and his team found that neither of these "nano" products work as advertised. "I began getting calls about reports that these things were being pushed in northern Indiana, and I thought, we need to prove or disprove the claims."

Carbon nanotubes  are one of the most controversial nanoparticles—often compared to asbestos for their ability to lodge into the lungs and cause trouble when they're breathed in.

So he and colleagues tested the products on a weed patch known to be glyphosate resistant, mixing them with glyphosate at levels recommended by the manufactures. The results, published in the trade journal Ag Professional, were underwhelming. On its own, Roundup (Monsanto's version of the glyphosate herbicide) killed just 13.8 percent of weeds. Mixed with ChemXcel, it killed 15 percent of weeds, while the called NanoRevolution 2.0/Roundup mix killed 18 percent of weeds.

Johnson explained that herbicides are always mixed with adjuvants—they're typically needed to help the herbicide penetrate a weed's outer layer. But these particular ones perform no better or worse than conventional adjuvants on the market. But they don't come anywhere near to solving the herbicide-resistance problem, as the companies claim to do.

C.J. Mannenga, co owner of C&R Enterprises, pushed back strongly on Johnson's assessment and challenged his results. "We know our product works," he said. "We've shown it in Georgia, we've shown in Ohio, we've shown it in Missouri, we've shown it in Iowa," he said. When we spoke Tuesday afternoon, Mannenga told me that he was in Osborne, Kansas, about to "meet with a major [agrichemical] distributor" who is "extremely interested in the product ... I'm going to do a demonstration to show them indeed it does work."

While the product's information sheet doesn't list its active ingredients, he readily revealed it to me: "it's just carbon nanotubes."

Carbon nanotubes  are one of the most controversial nanoparticles—often compared to asbestos for their ability to lodge into the lungs and cause trouble when they're breathed in. This 2014 assessment by researchers at the University of Massachusetts at Lowell is hardly comforting:

Though ecosystem impacts remain understudied across the CNT [carbon nanotube] lifecycle, evidence suggests that some aquatic organisms may be at risk. While there have been significant advances in the regulation of CNTs in recent years, the lack of attention to the potential carcinogenic effects of these nanomaterials means that current efforts may provide a false sense of security.

Meanwhile, no one employed by NanoRevolution 2.0 maker Max Systems returned my request for comment.