Cancer in the Corn Belt Sparks Actions to Fight Farm Fertilizer Nitrate Contamination

Yves here. This story somewhat buries the lead. The reason several Farm Belt states are teaming up is out of concern that the runoff from nitrogen fertilizer is getting toxic nitrates into water supplies…and the level the EPA deems to be acceptable looks to be too permissive. Note this concern is not new, as a 2016 article from EcoWatch demonstrates. But the fact that some states are saddling up may change the equation.

By Keith Schneider, a former New York Times national corresponden and senior editor for Circle of Blue. He has reported on the contest for energy, food, and water in the era of climate change from six continents. Originally published at The New Lede

When directors of the public water utility in Des Moines, Iowa, went to court in 2015 to try to stop toxic farm nutrients from contaminating the city’s drinking water, they knew the federal lawsuit they filed would be seen as not just a desperate step to protect public health, but also a brazen act of defiance that would provoke a ferocious response from Iowa’s powerful farm and political leadership.

As they anticipated, a cohort of agricultural interests joined then-Gov. Terry Branstad in beating back the lawsuit, which Branstad declared an act of “war on rural Iowa.” Des Moines Water Works alleged that drainage districts in three Iowa counties had polluted the Raccoon River with nitrates, forcing costly efforts by Des Moines to render the polluted water safe for drinking. The case was dismissed in 2017 after a court ruled that Iowa law immunizes drainage districts from damage claims.

It was the last time a government entity in Iowa or any other Corn Belt state made a focused attempt to reduce human exposure to suspected cancer-causing commercial fertilizers and a flood of livestock manure that routinely drains from farm fields into groundwater, streams, and rivers.

Until now.

Prompted by compelling research showing that cancer-related diseases and deaths are climbing as contamination from common agricultural chemicals and manure increases in key farm states, lawmakers and health officials in Iowa, Minnesota, and Nebraska are pursuing an array of new strategies aimed at reducing the risks to human health presented by the ongoing farm-related contamination.

A top concern for lawmakers and health professionals in the three states is reducing exposure to nitrates, which form when nitrogen from fertilizer and manure combine with oxygen. Babies can suffer severe health problems when consuming nitrates in drinking water, and a growing body of literature indicates potential associations that include an increased risk of cancer.

“It’s pretty obvious that in the areas where levels of nitrates and other agrichemicals in water are higher, you get more pediatric cancers and birth defects,” said Eleanor Rogan, chair of the Department of Environmental, Agricultural, and Occupational Health at the University of Nebraska Medical Center. “So that sort of tells you maybe you should do something about this and get the levels down.”

Iowa’s “Cancer Crisis”

Rogan is one of the leaders of Nebraska’s active epidemiological investigation into the state’s high rate of birth defects and pediatric cancers in areas where groundwater is contaminated with nitrates and atrazine, a weed killer. State lawmakers last year approved $2.5 million to add a pediatric oncologist unit to the team of scientists and medical specialists at the Medical Center charged in part with identifying and controlling the sources of cancer in the state’s children. In 2022, the legislature approved grants available to households and communities to develop new sources of uncontaminated groundwater.

In Iowa, first-term Democratic state Rep. Austin Baeth, an internal medicine specialist from Des Moines, is leading a bipartisan effort in the state legislature to end what he calls “Iowa’s cancer crisis.” Working with Democrats and Republicans, Baeth says a number of bills are being drafted for legislative consideration later this year.

“One of the policies we are pursuing is to dedicate state resources to cancer epidemiology for us to start to try to find some of those linkages to figure out what are the key drivers of our cancer rate,” Baeth said. “I have been successful in finding champions on the Republican side who share my concern.”

A proposal that Baeth and colleagues are developing would fund an epidemiological research program to more precisely evaluate potential causes of cancer, identify the sources of exposure, the number of people sickened, and the places where excess cancers are developing.

The research findings would complement the Iowa Cancer Consortium project to better understand and make the case for limiting exposure to pesticides, commercial fertilizer, and animal manure used and generated by Iowa agriculture, among other environmental contaminants.

“I cannot say that we conclusively know that nitrates are the cause of our exceedingly high cancer in Iowa,” said Baeth. “But certainly nitrates and other potential toxins in the water are on the list of potential culprits. We know that high nitrate concentrations are linked to cancer.”

In Minnesota, state Rep. Rick Hansen, the Democratic chairman of the House Environment Committee, is introducing a bill this year that levies what he calls a “polluter pays” tax on commercial fertilizer to help families and communities develop clean sources of drinking water. Minnesota farms apply roughly 3 million tons of commercial fertilizer annually, according to state figures. A $1 per ton tax on fertilizer that now sells for $720 a ton would raise $3 million.

Hansen’s proposal is a response to some of the nation’s worst nitrate contamination found in groundwater and drinking water wells in nine southeast Minnesota counties. In November, the US Environmental Protection Agency ordered Minnesota to address “imminent and substantial endangerment to the health” of thousands of residents who were being exposed to high levels of nitrate contamination in their drinking water.

Since 2010 Minnesota has spent an average of $103 million annually to prevent water pollution from its sales-tax funded Clean Water, Land, and Legacy Fund. The fund modernized water treatment plants and preserved 17,000 acres along streams and rivers as unplanted natural areas. The fund also provided low interest loans to 1,100 of the state’s 67,400 farms to deploy voluntary best management practices to stem the flow of nitrates into water.

Yet contamination, according to the most recent state assessment, is getting worse. New approaches are needed, starting with a fertilizer tax, Hansen said.

“If we are in a public health crisis with high nitrates, you got to find a good alternative water for those people,” said Hansen, who represents the Twin Cities metropolitan area. “Who’s going to pay for it? I don’t believe that the general taxpayer should pay for it.”

Hansen’s proposal is supported by influential lawmakers in the state Senate, among them Sen. Matt Klein, the Democratic chairman of the Senate Commerce Committee, and an internist in Minneapolis. “The polluter pays for cleanup in the state of Minnesota,” he said. “If kids are drinking water that has been poisoned by nitrogen fertilizer, then the makers of nitrogen fertilizers need to help us fix that problem.”

“A Real Problem”

The steps taken by three of the nation’s largest farm states comes in response to long-term trends in agricultural production, water quality, and public health that converged over a decade ago and have intensified since.

The amount of nitrogen applied to corn, considered a necessity to boost yields, has increased 120 million poundsannually since 2000, according to the US Department of Agriculture (USDA). And the amount of nitrogen-rich and untreated liquid and solid manure from livestock being spread on farmland – most of it in the Midwest – grew to 1.4 billion tons by 2018, 300 million more tons than in 2007, USDA data shows.

Commercial nitrogen fertilizer and nitrogen-rich livestock and poultry manure are the leading sources of nitrate contamination that is increasing in the region’s surface and groundwater, according to state environment and agriculture agencies. According to many studies, as much as 70% of the nitrogen applied to farmland leaked off fields and drained as toxic nitrates into the region’s waters.

In Minnesota, for example, farmers are buying more commercial fertilizer. And the state’s immense population of hogs, cows, and poultry is producing nearly 50 million tons of liquid manure. The most recent state assessment found “nitrates are increasing in major rivers,” and “since 1992, there has been a general increase in the percent of new wells that have nitrate levels above the drinking water standard.”

The science tying nitrates to cancer also has been building over the last 20 years and continues to build. Medical researchers have been conducting epidemiology studies, looking at large groups of people and what they’re exposed to and their rates of cancers. The results, some scientists say, indicate that exposure to nitrates in drinking water poses a health threat at much lower concentrations than the 10 parts per million (ppm) federal drinking water standard.

In 2012 the US Centers for Disease Control and Prevention (CDC) reported that the incidence of cancer in Iowa,Nebraska, Minnesota and two other states in the Corn Belt – Ohio and Wisconsin — was  increasing, even as the overall incidence of cancer in the US continued a decades-long decline. Just three states outside the Corn Belt experienced the same upward trend in incidence – Arkansas, Louisiana, and West Virginia.

Last year, alarm bells finally started to ring in Iowa when the state Cancer Registry reported that its citizens were suffering with the second-highest incidence of cancer in the US. The latest CDC data also found that in five other Corn Belt states – Illinois, Minnesota, Nebraska, Ohio, and Wisconsin – the incidence of cancer ranked near the top.

Digging into the data even deeper — of the counties across the country with the highest incidence of cancer, according to the CDC, Palo Alto County in Iowa has the second highest incidence, and four others in Nebraska are in the top 25.

“At some point as a society we’re going to have to say, ‘Well, do we want to expose everybody to all these agricultural chemicals?’, said Rogan of the University of Nebraska Medical Center. “Everybody’s ending up being exposed to them and that’s a real problem.”

 (This report, co-published with Circle of Blue, was made possible by an investigative reporting fellowship awarded by the Alicia Patterson Foundation and the Fund for Investigative Journalism. It is part of an ongoing series looking at how changing agricultural policies are affecting human and environmental health.) 

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  1. PlutoniumKun

    The links with nitrate pollution of groundwater and cancer and ‘blue baby’ syndrome go back to the 1970’s and has been confirmed in numerous studies. the 1991 EU Nitrates Directive set out timetables and action plans to tackle the problem. Unfortunately, the power of farming lobbies has led to endless delays and derogations. The EU finally started to act (aided by Brexit, as the UK farming lobby was the biggest defender of derogations). But the last resort of the farming lobby has been, as we’ve seen in the Netherlands and France, to claim that its all a big evil EU plot to hit small farmers (its actually the big industrial farms that cause most of the problems, but small farmers aren’t innocent either).

    Ultimately, this comes down to agriculture systems that incentivise intensification over and above the levels the soils and geology can handle – exacerbated by governments maintaining inputs at an artificially low rate. In Europe farmers are claiming innocence, despite a quarter of a century of warnings. Ironically, the war in Ukraine may be the saviour of groundwater in Europe as most nitrogen is produced through natural gas, and so is increasingly uneconomic. But without it, there is no more cheap dairy produce or animal feed. This shouldn’t be a problem – we should all be eating more legumes, not pork and milk, but we are very wedded to our cheap animal fats.

  2. McWatt

    We still have in our family our great-grandfathers family farm in Northeast Iowa. Our caretaker lost his 17 year old son to knee cancer. Our ground water is undrinkable. It seems every time we go for a visit there is a fund raiser for a kid with cancer or an adult with cancer. We contribute every chance we get.

    In our area farmers have stripped the land of trees to increase acreage for yield. Where there use to be woodlands all along the river that acted as a buffer for fertilizer run off, these are all gone. The 2 million trees that Frankie Roosevelt planted as wind breaks along the main roads to keep the soil in the fields are almost all gone. The farmers cut them down to increase their acreage. When you see one it is a treat.

    Glad to see that there is finally recognition of the problem in the state.

  3. earthling

    There has been a feverish drive to increase yields over the last few decades, with corn plants being crammed as tightly together as possible, their leaves unnaturally deep green from the max dose of fertilizer.

    Big Ag and little ag have known their over-fertilizing has created a persistent and often huge dead zone in the Gulf of Mexico for decades. Some care, but no enough to change it; more, including the corporate farms, do not give a damn.

    Will cancer close to home change things? Not if the CEO lives in a gated suburb elsewhere.

  4. Bruce F

    Chris Jones, who used to monitor water quality for the Univ of IA, and has a PhD in Chemistry, has a fantastic substack “Swine Republic“. His latest post breaks down the “logic”/”economics” behind the nitrogen pollution in the corn belt.

    This is the harsh math associated with nitrate pollution.

    Overall nitrogen inputs in Iowa (commercial fertilizer plus applied manure N) are much more aligned with the 2nd scenario (200 lbs/ac) than the first (146 lbs/ac). Despite what you might hear about nitrogen being expensive (it’s not, really) and that farmers don’t want to lose it, many if not most corn belt farmers consciously make fertilization decisions KNOWING FULL WELL that those decisions are more likely than not to create unnecessary pollution.

  5. flora

    Is it fertilizer or is it monsato’s Roundup (glyphosate) herbicide sprayed on soybean and corn fields grown from “Roundup ready” seeds? Or both/

    Bayer ordered to pay $2.25 billion after jury concludes Roundup weed killer caused a man’s cancer, attorneys say


    Exposure to chemical in Roundup increases risk for cancer, study finds

    1. PlutoniumKun

      Unfortunately, nitrate is a very powerful pollutant, likely far more hazardous in the long term than Roundup or similar – although the two are interlinked as they are both key elements of very intensive agriculture.

      Nitrate is the final form of nitrogen and ammonia when it runs through soil – it is highly soluble and very persistent, hence when there is an excess in the soil it almost inevitably ends up in groundwater and freshwater systems. Usually its very obvious in surface water (nasty blooms and eutrophication almost immediately), but its far more insidious in groundwater. Its there pretty much forever.

      One key issue is that there are so many potential sources – nitrogen fertiliser, organic materials, septic tanks, landfills, etc., that its very difficult to pin down the specific polluter, which of course gives farmers (and others) free reign to pretend its someone else’s problem.

    2. steppenwolf fetchit

      Wouldn’t it be “interesting” if nitrates and glyphosate both “force-multiplied” eachother’s carcinogenicity?
      Which means that removing and/or preventing either one would be helpful in terms of reducing the “force-multiplier” effect, if there is one.

      And if we are already beginning with counter-nitrate action, why not keep beginning with more counter-nitrate action?

  6. Mary Parker

    Flora, neither one, nor both, nor a trifecta:

    Nitrates washing into algae blooms,
    Genetically modified seeds tricking your gut biome into making toxins that cause allergies, or Crohn’s or cancer,
    Roundup killing the soil life, and you,
    Other chemicals doing the same…

    Let’s not even mention the concentrated ownership of the land by Gates and Chinese billionaires. The way to avoid most of the above is to only eat organic.

  7. Lunker Walleye

    There are twenty-two homes on our central Iowa street. Just under 50% of these households have had a cancer in the four decades we’ve lived in our home (that I’m aware of). There have been at least four breast cancers — I’m one of three survivors, and there was one death. There was a little girl who died from leukemia. My next door neighbor passed from a rare blood cancer, and on the other side of us our male neighbor had bladder cancer. Another neighbor had lung cancer and recovered and one died from it. There is a lot of round up use on the street but there is also high levels of radon. Several of the homes now have radon mitigation. We are one of them. Our water used to be wonderful and now it tastes of chemicals.

  8. Susan the other

    Nitrogen? Well, just fucking shit, as they say casually. But it is not a casual thing. But it becomes a casualty. Big mental disconnect here. Let’s call it an irrational rationalization, or is that by definition redundant? Anyway, nitrogen is a poison and “poison is the dose” so that we have to balance abundance (profits) by balancing the well being of Nature (which includes us as we attempt to stretch our boundaries).. This nitrogen pollution can be very devastating and expensive if we ignore it. And that is the thing (our neglected balance with nature) that is totally out of fucking whack, no? Should we bomb Iran for more oil or should we learn to live within our natural boundaries and by so doing validate the rest of the world when they do so too?

  9. Tedder

    It is ironic that manure, once a precious fertilizer for garden and farm, has become toxic, carcinogenic waste. It is also ironic that nitrogen, a freely available gas fixed into the soil by plants, joins the cancer club.
    We observe in neoliberalism an emphasis on short-term gains and expansion without any regard for consequences. Modern industrial agriculture practices are neoliberalism gone awry as its short-term practices neglect long term soil health and now, we see, neglect public health. Organic farmers and gardeners have been telling this story for many years, but no one listens, just as no one listens to politics that might help.

    1. steppenwolf fetchit

      Someone has listened. Those people who buy organic food have listened. Those people who grow organic food have listened.

      It is true that almost no one listens, but the difference between almost no one and no one is like the difference between zero and one.

  10. Rip Van Winkle

    1. ban atrazine
    2. end ethanol-related subsidies

    Any candidate talk about this subject in Iowa a couple of weeks ago? Ever?

    1. steppenwolf fetchit

      Ted Cruz said ” ban ethanol-related subsidies” when he was running in the 2016 primaries.

  11. redleg

    I’ve been involved in the Minnesota part of this, as both a regulator and a consultant. I led the MN DNR 2015-2018 Dakota County surface water – groundwater interaction study that quantified vertical leakage between the surface and the deep Jordan Sandstone aquifer that many experts thought was not possible. Nitrate is an excellent indicator for other agricultural chemicals. If agricultural nitrate is in an aquifer, then every other agricultural chemical is also there in some amount.
    When a regulator shows up in a farming community to talk about nitrate contamination, or chemical use, or even irrigation practices (MN does NOT have senior water rights of any kind. Water is constitutionally a public resource in MN), the most vocal of the farmers will declare that “the State hates farmers!!” to the media and all who will listen. This has been a political cudgel for them, beating legislators back from attempts at regulation or towards deregulation. The less vocal farmers just want to have clean drinking water for their communities, livestock, and wildlife now and 100 years from now so that their communities can continue to exist.
    Both sides of this issue are dominantly Republican. If the Dems would stop insulting these people by calling them deplorable (etc.), they could win them over and we could have nice things, like clean water.

    One other observation is that Minnesota has the legacy amendment that provides abundant funding for environmental research and remediation, but lacks the legal framework to do anything about agricultural pollution. Most other States have the cast iron legal authority to handle agricultural pollution, e.g. Wisconsin has water quality regulation written into the State constitution, but no funding mechanism so no regulatory action happens due to lack of resources. ND is in the same situation. I don’t think Iowa has either of the two.

    1. steppenwolf fetchit

      Back when Minnesota had its own Farmer Labor Party, how many ( what percent) of farmers voted for it?
      When Farmer-Labor became New Deal Democrat or at least Newish Dealish Democrat, how many farmers would have voted for it?

      How many of the people who vote for Minnesota Republicans now would have voted for Hubert Humphrey or such back in the day? Back before Democrats became Clintonites and didn’t find farmers deplorable?

    1. steppenwolf fetchit

      Many of the Indian Nations people were planet-friendly. Some still try to be. The Ba m’Buti Pigmies of the Ituri rain forest are planet friendly. Other indigenous peoples are planet friendly. Are they a different species than the human species?

      Or do Western-Modern civilization persons mistake “Western-Modern Civilization” for “human species”?

  12. elviejito

    Here’s what’s happening in Nebraska in re: nitrates
    The article barely mentions runoff from CAFOs. The governor, Jim Pillen, runs a large hog operation which led to the following ditty:
    Governor Pillen had a farm
    And on that farm he had some pigs
    With an oink-oink here and an oink-oink there
    Here an oink,
    There an oink,
    Everywhere an oink-oink
    Governor Pillen had a farm
    Governor Pillen had a farm
    And on that farm he had some nitrates
    With a nitrate here and a nitrate there
    Here a nitrate,
    There a nitrate
    Everywhere a nitrate
    Governor Pillen had a farm

    Now there’s nitrates in the water well
    There’s nitrates in the baby’s bath
    There’s nitrates in the swimming hole
    There’s nitrates in your cuppa joe
    Governor Pillen had a farm

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