by Ted Genoways
In the fall of 2013, the CDC and the Center for Science in the Public Interest (CSPI) issued a report raising fears that the bacteria in CAFO waste pits might be breeding grounds for antibiotic-resistant bacteria. “Because of the link between antibiotic use in food-producing animals and the occurrence of antibiotic-resistant infections in humans,” the report said, “antibiotics should be used in food-producing animals only under veterinary oversight and only to manage and treat infectious diseases, not to promote growth.” Food safety activists applauded the recommendation, but worried that its voluntary enforcement didn’t go far enough. They warn that the increasing numbers of superbugs in our food when combined with our growing tolerance of critical antibiotics may be setting the stage for livestock illnesses to make the leap to human hosts, causing a severe and deadly outbreak.
New Fashion Pork’s herd manager assured me that the company does not use antibiotics to promote growth and that none of its courses of antibiotics feature drugs critical to treating human illnesses. However, the company’s last published set of instructions for barn managers to follow in reducing medications before slaughter listed eight injectable antibiotics, ten water-soluble antibiotics, and five feed-additive antibiotics that New Fashion Pork regularly administered to its pigs. Among those most commonly used were penicillin, amoxicillin, and neomycin—some of the most widely prescribed antibiotic treatments for human patients in the United States and around the world. Their hogs were also frequently given Chlortetracycline (CTC) and Oxytetracycline (OTC), marketed under the names Aureomycin and Terramycin. Not only are these antibiotics the most common drugs used by the hog industry to speed growth among piglets; they were first mass-produced and marketed after World War II by Hormel scientists for precisely that purpose.
In the fall of 1941, Jay C. Hormel invited a group of medical researchers at the University of Minnesota to his estate outside Austin. He wanted to share an idea. There was a large horse barn on the grounds, which he believed might be converted into a laboratory space. The scientists agreed and consulted on the creation of a 400-square-foot lab. A year later, the Hormel Foundation, the company’s charitable wing, announced a partnership with the University of Minnesota to create the Hormel Institute—a facility officially founded to study “the relation of animal products to disease and to the treatment of disease,” but, in reality, intended to search for ways of improving hog production. The university would supply the researchers, both professors and gifted graduate students, and Hormel would provide the space and funding. Because their research might have medical application, they also agreed that the supervisory board should include a permanent spot for a representative from the Mayo Clinic.
At first, the institute was little more than one chief laboratory technologist, Jacques R. Chipault, a doctoral student at the University of Minnesota, still sharing space in the barn with the stable of horses. But in 1945, with the war ended and demand for cheap meat soaring, the institute’s staff was expanded to eight, including Lawrence E. Carpenter, a newly minted Ph.D. from the University of Wisconsin. That same year, Carpenter’s former professor, Benjamin Duggar, a botanist who studied fungal infections in plants, reached mandatory retirement age at Wisconsin and took a job at the Lederle Laboratories Division of American Cyanamid in Pearl River, New York. Merck, a chief competitor for American Cyanamid, had saved the lives of countless wounded GIs by the mass production of the wonder drug penicillin before the invasion of Normandy and had recently begun manufacturing streptomycin to combat tuberculosis. American Cyanamid was hoping that Duggar would discover the next antibiotic marvel.
Duggar started by trying to solve an old farmyard mystery: why did chickens raised where they could peck through manure experience lower mortality rates and higher egg production than pullets raised in “cleaner” environments? He suspected the chickens were benefiting from antibiotic fungi living in the soil and fed by manure. Duggar ordered soil samples from research farms across the country, eventually testing more than 3,500 vials of dirt before a sample from the University of Missouri yielded an unusual gold-colored mold with miraculous benefits. Duggar discovered that the drug—which he named aureomycin from the Latin for gold (“aureus”) and fungus (“mykes”)—had antibiotic effects against 90 percent of the most common forms of bacterial infection in humans. Doctors who began testing the drug in hospitals reported its effectiveness against everything from whooping cough to typhus, but they found that it was especially effective against amoebic dysentery and other intestinal infections. And the drug not only halted life-threatening diarrhea but had an interesting side effect: the patients actually put on weight.
Thomas H. Jukes, a biochemist in the agricultural division at Lederle who had been searching for an effective animal feed additive, wondered if aureomycin would have the same effect on livestock. Knowing its origins as a natural defense among chickens, Jukes gave baby chicks feed mixed with aureomycin, culled surreptitiously from Duggar’s lab waste, and found that the test chicks grew as much as 50 percent larger than the control group. He published his results and immediately set out to find if similar outcomes could be achieved with hogs—and young Lawrence Carpenter at the Hormel Institute was eager, too, to test this new application of his former professor’s discovery.
So, in early 1950, Lederle Laboratories provided a supply of aureomycin for Carpenter to test at the horse barn in Austin. By April, he had conclusive evidence that supplementing the normal diet of a weaned piglet with a daily dose of the antibiotic could more than double feed efficiency. Carpenter announced the results in the Hormel Farmer, the free newsletter sent out to all of the company’s hog suppliers. By June, small town newspapers across Iowa and Minnesota were running advertisements touting aureomycin as “the most important advancement in Swine Nutrition in the last 25 years.” Soon, even the Wall Street Journal was reporting that 85 percent of runts “given aureo in their feed survived and grew up into self-respecting hogs.” Lester E. Corson of Lyle, Minnesota, told the reporter that he had decided to try the supplement with his runts. “Now they actually look like they are going to make good market hogs.”
By the end of 1951, Jay Hormel told shareholders that the Austin plant was nearing its capacity in terms of animals it could process in a day, but he foresaw continued growth in the number of pounds of pork they could produce each year, thanks to antibiotics. Not only was aureomycin allowing hogs to be “brought to marketable weight more quickly,” but now Hormel scientists were experimenting with weaning piglets sooner—and even feeding them artificial milk laced with antibiotics, which could replace the natural immunity built up by breastfeeding. Jay envisioned a future where sows could give birth and go directly back into breeding. “This could mean that they might immediately be put back to work producing another litter,” Hormel said, “instead of consuming eight pounds of feed a day for fifty-six days, performing no other service than can be performed by the milking machine at the nearest dairy.”
Best of all, the Hormel Institute, which had seen devastating mortality rates among their barn-raised test herd due to the rapid spread of illness, was seeing those losses almost entirely eliminated. Being able to keep hogs safely indoors through the winter—and even breed them during that time—would mean tremendous gains in the number of piglets Hormel’s farmers could raise each year.
Amid all the good news, researchers sounded one note of caution. Carpenter himself recorded that aureomycin was believed to bring about weight gain by wiping out intestinal flora that might otherwise constitute competition for nutrients in the hog’s digestive tract. Because the uptake of the antibiotic was focused on the gut, he wondered if the aureomycin might be passing through the hogs and into the manure that farmers were being encouraged to use as natural fertilizer. To mitigate this effect, he experimented with injected antibiotics but found “that aureomycin, administered either orally or by injection, is excreted in the feces of pigs.”
Researchers hoped that this might not pose a problem; if aureom
ycin wiped out all bacteria in a hog’s digestive tract, then the feces might actually emerge as a safer manure. It might even produce hogs free from disease. But scientists at the University of Illinois soon discovered just the opposite to be true: for the first nine days of receiving the antibiotic, they found, there was “a marked decrease in the coliform organisms in the feces of the pigs,” but after that the levels began to equalize until at sixteen days “this difference had disappeared.” This data sequence suggested that antibiotic-resistant E. coli were breeding inside the pigs’ intestinal tracts, yielding a manure laced with super bacteria. And already three physicians at the University of Illinois College of Medicine reported: “Although aureomycin has been in general use for only three years, there is evidence that resistant strains of staphylococci are appearing in hospitalized patients.”
Despite this early concern, the problem was kept in relative check for decades. In the 1950s and 1960s, few hogs were raised in year-round confinement, so their manure was rarely concentrated enough to pose a public health risk. Then, in the 1970s, with the passage of the Family Farm Protection Act in states across the Midwest, there were decades in which the ban on vertical integration kept large-scale hog confinements from being economically viable. But when the bans on corporate backing of concentrated animal feeding operations began to fall, thousands of mega-barns sprang up, bringing their massive lagoons and enormous concrete waste pits along with them.
In 2002, just as the CAFO building boom in Iowa was beginning, the University of Iowa and Iowa State University published a joint report investigating complaints of a litany of illnesses, particularly eye lesions and chronic respiratory problems, among people living near CAFOs. The investigators concluded that air pollutants in the form of hazardous gases from hog confinements were a plausible source of the illnesses. Large-scale confinements, they wrote, “may constitute a public health hazard”—and explained that the problem did not arise primarily from the containment of manure in waste pits but from its application aboveground as fertilizer, attributing fully 80 percent of air exposure to the first six hours after it was spread.
In response, the Iowa DNR announced new air-quality regulations. But state lawmakers overruled those standards within days. While they were eager to keep out-of-state meatpackers from crowding into Iowa, they didn’t want to hamstring potential development for local hog producers. So, in place of more stringent air quality constraints, stopgap guidelines were established requiring liquid manure to be immediately knifed into the topsoil or directly injected into the subsoil, preventing harmful gases from escaping into the air. Soon after, Iowa adopted a more elaborate scheme known as the Master Matrix Plan—a scoring system, to be implemented and enforced by the DNR, that would evaluate the siting and manure management practices of proposed large-scale operations.
Critics say that the Matrix is both a virtual rubber stamp for industry and intentionally byzantine to make it hard for watchdog groups to monitor compliance. The system determines permitting based on forty-four factors—covering air quality, water quality, and community impact—each assigned a maximum value of twenty points. The Environmental Protection Commission decided that a passing grade would be 440 points—or half of those available. Steve Roe, president of the Raccoon River Watershed Association, bitterly denounced the system one night at a potluck dinner of landowners opposing new construction of hog confinements. “Whoever heard of passing a test with a score of fifty percent?” Roe pointed out that the test is really a self-exam with results submitted for certification and approval. In most cases, counties and municipalities have no means to check Matrix submissions for compliance. One DNR inspector told me that many county supervisors do not attend visits of potential sites when they are offered by the department. And even in cases where a county does object, the builders can appeal directly to the political appointees who head the DNR. Roe said he didn’t know of a single instance in which the department had denied a permit request.
As the building of CAFOs boomed and the state’s hog inventory tripled in a few short years, the quantity of waste grew too. David Goodner, a spokesman for the watchdog group Iowa Citizens for Community Improvement, told me that the state’s factory farms now produce well over five billion gallons of liquid manure a year. He said the volume of applied fertilizer is now so high that the ground simply can’t hold all the manure being produced, especially in recent years as spring rains have sheeted off drought-hardened fields. The daily loads of antibiotics, drug-resistant bacteria, and nitrates began regularly violating levels allowed under the Clean Water Act, leading to renewed worries about the immense number of antibiotics being administered to livestock and the potential impact on humans.
When a rash of MRSA was reported in 2008, health officials worried that the illness, which was already prevalent among hogs in Europe and other parts of North America, had spread to herds in the United States and was now jumping to human hosts. A representative for the National Pork Producers Council told a reporter for the Seattle Post-Intelligencer that there was “nothing to worry about.” No cases of MRSA had been found among pigs on “this side of the border,” he said, claiming that the USDA and CDC had issued “our pigs a clean bill of health.” But the CDC immediately denied having ever made any such statement.
In fact, Tara Smith, an assistant professor in the University of Iowa Department of Epidemiology, was in the midst of conducting the first scientific test of hogs for MRSA in the United States—and the findings were not nearly as reassuring as the Pork Council had suggested. Members of Smith’s team had swabbed the noses of 209 pigs from ten hog barns in Iowa and Illinois and found MRSA present in 70 percent of the animals. More disturbingly, two of Smith’s graduate students also took swabs from twenty workers at several Iowa farms and found that 45 percent of the workers were also culture positive.
Because the bacteria live primarily in the nose and respiratory system, Smith undertook another study—this time in partnership with Margaret Carrel, a specialist in the geography of infectious disease at the University of Iowa—to investigate whether MRSA might be spreading to people beyond the confines of the hog barns. The team gathered the records of more than a thousand patients from rural Iowa who had been admitted to the Iowa Veterans’ Affairs Hospital with respiratory complaints in 2010 and 2011. In all, they found that 119 of the patients were suffering from MRSA. That rate in itself was distressingly high, but the greatest shock came when the home addresses for those patients were overlaid onto the Iowa DNR’s map of CAFOs. The overwhelming number of patients with MRSA lived within one mile of a hog confinement. They were three times more likely to have the antibiotic-resistant bacteria than other residents of rural Iowa—and nearly ten times more likely than someone living in an urban area.
The researchers were unable to say exactly how MRSA was making the jump from the confined hogs to the workers in the barns and the nearby residents, but they noted that manure from CAFOs is typically spread as fertilizer on the corn and soybean fields surrounding the barns. “MRSA can be aerosolized from this manure to human food or water sources,” they concluded. “The increasing populations of swine raised in densely populated CAFOs and exposed to antibiotics presents opportunities for drug-resistant pathogens to be transmitted among human populations.”
Brad Freking at New Fashion Pork told me that he simply didn’t believe that antibiotics could be passing through his hogs and producing resistant bacteria in his waste pits. “A lot of those antibiotics are broken down within the pig by the time it goes through the liver and the kidney. What the pig is actually urinating into the pit is a changed molecule. You see where I’m going?” he asked rhetorically. “If I put tetracycline into the pig, what is that molecule that comes out? Then, it sits in an active pit. Does it get broken down or changed again? I don’t know.” But recent research indicates that as much as 80 to 90 percent of tetracyclines and other common antibiotics are still in active form when excreted by hogs. And far from hostile environments to
bacterial growth, waste pits have been shown to be an ideal breeding ground for antibiotic-resistant strains of E. coli and S. aureus. Officials from the Des Moines Water Works assured me that their filtration systems, and those used in most local municipal water treatment plants, do an excellent job of removing antibiotics and bacteria from the water supply. But those downstream systems do nothing for people taking their water from wells near hog confinements or who live in homes neighboring fields where the application of manure releases antibiotic-resistant bacteria—and other contaminants—into the air and soil.
The University of Iowa researchers were unequivocal: “Our study indicates that residential proximity to large numbers of swine in CAFOs in Iowa is associated with increased risk.”
Chapter 14
LAY OF THE LAND
Jay Lausen parked his pickup on the side of the gravel road and walked out to the edge of the field. This was the quarter section of land he had wanted me to see, and he stood quietly, letting me take it all in. But this 160-acre plot, just north of Estherville, Iowa, and only a few miles from the Minnesota border, didn’t look much different from any number of cornfields stretching away in all directions—not to my eye, anyway. It was November now, and I could see that the rows had been harvested, the brown stalks chopped to stubble, and someone had recently applied rich, dark fertilizer, ahead of the hard frost that would be coming soon. But, beyond that, I didn’t see what was so special about this particular parcel of land.
Lausen smiled. He had spent twenty years farming this field for a neighbor and had mastered its every contour. He lifted his finger and traced the spinelike ridge that divides the acreage, then the serpentine gully that winds toward the southwest fence corner where runoff pools and swells into a culvert. That west side of the property, he explained, is sloped enough that in the early 1990s he had enrolled some fifty acres of it into the Conservation Reserve Program (CRP), an initiative by the U.S. Department of Agriculture to take environmentally sensitive land out of crop production by paying farmers to instead plant native grasses, tall deciduous trees as windbreaks along property lines, and evergreens to hold soil along waterways.