Maryn McKenna

Journalist and Author

WCSJ: Plant Diseases, Farmer Suicides And The Peril of A Hungry Future

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Here’s my second report from the World Conference of Science Journalists — and if you thought the first one on diabetes in China was depressing, just wait for this one.

Since I wrote SUPERBUG the book and started this blog, I’ve been fascinated by stresses and problems in food production. (For evidence, see any of this long archive.) This conference in Qatar, which drew 726 journalists, most from the global south, was a chance to hear from people  immersed in food issues in places we in the north don’t know enough about. So for my panel on agriculture and food security, I invited people whom I wanted to learn from.

And wow, did I.

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WCSJ: Maybe The Biggest Disease Threat Isn't Infectious At All

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I’ve been away the past week at the World Conference of Science Journalists, a biannual gathering that brought 726 writers and broadcasters from 87 countries to Doha, Qatar. I was there to give a presentation about blogging, and also because I organized two panels on under-reported epidemics and on food and farming issues in the developing world. My panelists’ testimony was so powerful that I wanted to share some of the details.

Going into the conference, the epidemics panel was my favorite. That’s not because I cheated and made myself one of the speakers, but because it brought into public view so many of the disease-control issues that we talk about here. When I say hidden epidemics, what I mean is this: The diseases that routinely grab headlines are almost never the ones that cost society the most in illness and deaths, and also in money to control and repair them.

Think of Ebola, for instance. There has never been a case of human Ebola in the United States. And as I’ve written before, viral hemorrhagic fevers repeatedly have been imported to North America without ever starting an outbreak. Yet whenever Ebola sparks in Africa, it earns scare-font headlines here, as though it were about to rampage across the continent — even though, in all its known engagements with humans, Ebola has killed less than one-tenth of the 19,000 that MRSA, for instance, kills in the US in a single year.

I asked a set of distinguished health journalists, all friends, to come to Doha to talk about diseases that deserve headlines, but never get them. Here’s what they said:

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Is Drug Resistance in Humans Coming From Chickens?

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There’s a new paper out in the CDC’s journal Emerging Infectious Diseases that makes a provocative claim: There is enough similarity between drug-resistance genes in  E. coli carried by chickens and  E. coli infecting humans that the chickens may be the source of it.

If it is correct — and it seems plausible and is backed by past research — the claim provides another piece of evidence that antibiotic use in agriculture has a direct effect on human health.

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E. Coli: Some Answers, Many Questions Still

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The past few days have seen the simultaneous publication of the first vetted medical-journal pieces on the vast European outbreak of E. coli O104. They’re fascinating for what they report that is new about this perplexing epidemic — now up to 3,802 cases including 43 deaths, according to the World Health Organization — and also for the further questions they raise.

Possibly most headline-worthy: Two reports in Eurosurveillance, Europe’s peer-reviewed open-access epidemiology journal, that suggest this strain is communicable from person to person and also produces unusual and troubling symptoms.

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E. coli: What we know and need to

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The stream of news from the E. coli O104:H4 outbreak in Germany has been so steady that it’s been hard to catch my breath long enough to post on it. The Robert Koch Institute in Germany said today that they think the epidemic curve is cresting, which makes me unusually late to the party. Nevertheless, since there are likely to be more cases and more deaths — and a long struggle still to understand what happened — I thought it would be useful to count up the things that we can say for sure, and those that remain puzzlingly open questions.

First: Is this the largest E. coli outbreak ever? According to food-safety uber-attorney Bill Marler, this outbreak — more than 2,600 victims, 13 countries, 26 deaths (Nature News has a great graphic of cases by country) — is dwarfed only by a 1996 epidemic in Japan. (Here’s Marler’s list). If it’s not the largest, it is likely to have produced the largest percentage of serious illness: As of today, there are 725 cases of hemolytic uremic syndrome (689 in Germany, 33 in the rest of Europe, three in the United States), according to WHO-Europe.

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More MRSA, in milk: A new strain in cows and humans

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Despite the massive AIDS anniversary this week, I was expecting to write about the EU E. coli outbreak next. But there’s striking new news on MRSA that makes it worth putting off E. coli one more day. I’m traveling many time zones away from home, though, so this will be quick.

Researchers in England and Denmark have announced they have found a never-before recorded variant of MRSA in cow’s milk in England that has already caused human infections in England, Scotland and Denmark, and researchers in Ireland have simultaneously announced that they have found the same strain in hospitalized patients there as well.

Here’s how this unfolded:

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MRSA in meat: How much? Which? And more bad news.

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(Sorry for the radio silence, constant listeners. It’s been a challenging few weeks at Casa Superbug, with a death in the family and the chaos afterward of catching up to the rest of life. But back now, with some interesting stuff planned for later this week.)

Last week was the General Meeting of the American Society for Microbiology (ASM). This is the conference at which, several years ago, Tara Smith’s team at the University of Iowa first announced they had found MRSA ST398 in pigs in the United States, so it always bears watching for new MRSA news, and this year it didn’t disappoint.

First: I’ve complained persistently because the federal system that monitors antibiotic-resistant bacteria in animals and food, NARMS (National Antimicrobial Resistance Monitoring System) doesn’t include MRSA among the pathogens that it tracks. It is possible that might be changing — because at ASM, a team from the Food and Drug Administration reported the results of a pilot study that looked for MRSA in retail meat in the US and found it.

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Growth Promoters: If You Can't Convince Them, Sue Them

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A little less than a year ago, the Food and Drug Administration took a step that, depending on your point of view, was either far too activist or nowhere-near-enough-but-good-try: It proposed, in a draft document, that the agricultural industry voluntarily restrict its use of growth-promoting micro-doses of antibiotics.

It was a significant step. The FDA has been trying to restrict subtherapeutic use of antibiotics in livestock since the 1970s because of the practice’s clear contribution to the development of antibiotic resistance, and had always been defeated. At the same time, it was far from bold: The proposal was made in a draft document that would be made final at some unspecified future date, and that when it became final would have behind it no force of regulation or law. (Here’s my long discussion from last year of the context and history of FDA’s move.)

And there things rested, while the FDA’s docket reportedly filled up with thousands of comments from both sides of the issue. The document — formally, Draft Guidance #209, Judicious Use of Antimicrobial Drugs in Food-Producing Animals — is scheduled to be finalized sometime before the end of this year. But in its draft form, it excited abundant opposition, and the administration official who seemed to be leading the charge on it, memorably suggesting, “We have the regulatory mechanisms and the industry knows that,” has left the FDA for a state-government job.

Clearly, things aren’t moving very fast. So today, a coalition of nonprofit groups attempted to get the issue jump-started: They sued.

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Farm Antibiotics: 'Pig Staph' in a Daycare Worker

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It’s been just about seven years since an alert epidemiologist in the Dutch town of Nijmegen identified an aberrant strain of MRSA, drug-resistant staph, in a toddler who was going in for surgery to fix a hole in her heart. The strain was odd because it didn’t behave normally on the standard identifying tests, and because it had an unusual resistance factor — to tetracycline, a drug that it should not have been resistant to, because the Netherlands had such low rates of MRSA that tetracycline wasn’t being used against the bacterium there.

Pursuing the source of the strain, researchers at Radboud University found it in the toddler’s parents and sister, and in the family’s friends. Not knowing where else to look, they asked what the parents and their friends did for a living; discovered they were all pig farmers; and went to their farms, and checked the pigs, and found it being carried by them, too. Suddenly, that strange resistance pattern made sense: The Netherlands uses more antibiotics in pig agriculture than any other country in the European Union, and the drug that it uses the most is tetracycline. Clearly, the aberrant strain — known as MRSA ST398 for its performance on a particular identifying test — at some point had wandered into pigs, become resistant to the drugs being given to the pigs, and then crossed back to humans, carrying that new resistance factor as it went.

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Turning grief into action: Moms and antibiotic misuse

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In December 2007, I flew to Chicago to meet the team of researchers who spotted the first known cases of community-associated MRSA in the US in the mid-1990s, and who have been agitating ever since for recognition and action to beat back the rising tide of antibiotic resistance. It was grey and snowy outside their shabby suite of offices, carved out of University of Chicago’s long-replaced children’s hospital. I sat in a green-tinged conference room piled with stacks of articles while Everly Macario — a Harvard-trained ScD in public health, the daughter and sister of physicians — described how MRSA killed her toddler son Simon in less than 24 hours.

“We have no idea where he got it,” she told me. “We have no idea why he was susceptible.”

Simon Sparrow was 17 months old in April 2004, a big, sturdy child with no health problems except a touch of asthma. The day before he died, he woke up feverish and disoriented, startling his parents with a cry unlike anything they had heard from him before. It was a busy morning — his older sister had a stomach virus — but they got him to the pediatric ER, got him checked, and brought him home when doctors found nothing unusual going on.

A few hours later, Everly was working at home, watching both kids, and Simon’s breathing changed. Her husband James, a history professor, had driven a few hours away to give a speech. She called a friend who is a pediatrician, held the phone up to Simon’s nose and mouth so she could hear, and then got back on the line.

“Hang up,” her friend said. “Call 911.” [Read more…]

The biggest foodborne-disease threat may not be addressed by the new food-safety law

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So if we wanted to reduce the danger of pathogens passing to people via food — not just drug-resistant bacteria, which are an increasingly significant problem, but all disease-causing ones — where to start?

Formulating a strategy is more difficult than it seems. In the US, policing food safety is divided among several federal agencies: the FDA, USDA and CDC. The FDA has responsibility for most of the food supply, including seafood, produce, processed food and fresh eggs. The USDA’s Food Safety and Inspection Service (FSIS) regulates fresh meat and poultry and egg products. The CDC surveys the illnesses that result from any of them, estimating most recently that one in six US residents, or about 48 million people, get sick each year, 128,000 are hospitalized and 3,000 die.

But most of those illnesses are never investigated, because a substantial portion of them occur individually or in small clusters, not in major outbreaks. Many of them have long-term consequences that are never recorded by any federal counting mechanism. And there’s currently no surveillance system that links pathogens and food — which means there’s no way to target which foods, or food-raising practices, pose the greatest risks.

The new food-safety bill, signed in January, addresses at least some of those barriers, by requiring a risk-based approach to foodborne illness — meaning, you look at what is causing the greatest problem, and aim your efforts and funding in that direction. But the bill — which certain Congressmen have threatened to starve of funding — covers primarily the FDA. And a new analysis suggests that’s not where the greatest problems lie. [Read more…]

Multi-Drug Resistant Staph in 1 in 4 Meat Samples

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Much of the contentious debate over abuse of antibiotics in farming boils down to a couple of simple questions: Whether resistant organisms that arise on farms because of antibiotic use leave the farm, and whether, once they do, they reach human beings.

A piece of research due to be released this morning in the journal Clinical Infectious Diseases helps answer both those questions. (I received an advance copy under embargo; I’ll put up the link when the journal posts it. here’s the link to the full-text pdf.)

A team of researchers from Arizona bought meat and poultry in five cities across the United States, tested them for bacteria, and found this: 47 percent of the samples contained the very common pathogen Staphylococcus aureus, and 96 percent of those isolates were resistant to at least one antibiotic. Of more concern: 52 percent of those staph isolates were resistant to at least three antibiotics that are commonly used in both veterinary and human medicine.

That is: Roughly one in four packages of meat and poultry from across the United States contained multidrug resistant staph. [Read more…]

China pig crisis: Drug residues in pork

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In China, more than 2,000 tons of fresh pork and pork products — at a minimum, 4 million pounds — have been recalled because the meat has tested positive for clenbuterol, a stimulant that is illegal in food-producing animals not only in China but in Europe and the United States. Another 1.6 million pigs are being tested.

The story has been unfolding for the past week without much notice from Western media, but it has been heavily covered in China, even in English-language media there.

Clenbuterol, which lingers in muscle tissue for months and concentrates in some organs, is hazardous to humans because of its stimulant properties: It revs up the heart and gives you the shakes, and can be especially dangerous for pregnant women. (Here’s the data sheet from the Food Safety and Inspection Service.) If it sounds familiar, that’s because its stimulant qualities also make it a performance enhancer — and thus a banned drug for elite athletes, including a listing on the World Anti-Doping Agency’s Prohibited List. Tour de France winner Alberto Contador was temporarily banned from cycling this year after a positive clenbuterol test, and US Olympic swimmer Jessica Hardy was found positive for the drug in 2008 (a finding she blamed on an allegedly tainted supplement). Clenbuterol’s a common subject on body-building forums (here’s one example) for its perceived ability to build lean muscle while diminishing fat.

And that may have been the motivation in China: putting lean weight, inexpensively, on pigs.

Here’s what’s known:

On March 17, the Chinese TV network CCTV reported that 19 pigs at a slaughterhouse in Henan province, part of a lot of 689, had tested positive for clenbuterol in their urine. About 20 people — farmers, middlemen, quarantine inspectors and a buyer for the processing company, Jiyuan Shuanghui Food Co., Ltd. — were arrested.

On March 18, Xinhua News reported that the number of positive tests had grown to 52 pigs out of 1,512, on nine farms tested, and the number of people in police custody had grown to 30. Plus, the scandal had spread to a second province, Jiangsu, after 20 randomly picked pigs out of 264 from Henan tested positive at a slaughterhouse in Nanjing. Concern over the brewing scandal drew the central government’s Ministry of Commerce into the issue; the agency urged the company where the tainted pork was first found — which happens to be a subsidiary of China’s largest meat processor — to suspend production and start an internal investigation.

On March 19, the central government convened an emergency meeting of pig farmers, meat processors and food retailers, and two days later ordered provincial authorities to start a crackdown that extends to checking backyard pigs.

And on March 25, the government released its annual food safety plan and put special emphasis on banning clenbuterol and tracking down illegal users.

Notably, the more-free parts of the Chinese media are pushing the government to do more. China Daily editorialized on Thursday:

Why can’t quarantine workers go to pig farms in a random way to check the pigs? Why do they have to wait for the pig urine sent by pig raisers? Why aren’t pigs randomly checked immediately before they are butchered? What is both funny and sad is the fact that a local bureau of animal husbandry in central China’s Henan Province checked a problematic pig farm and 98.8 percent of the pigs tested were passed safe on March 15. But an investigation by reporters after the check found that the farm still feeds pigs clenbuterol, which was banned nine years ago.

The revelation that pigs are being fed growth hormones that are considered harmful to humans so the animals develop more muscle and less fat has shaken consumers’ confidence in pork, just as the melamine scandal did with milk. Anyone involved, whether pig raisers or quarantine checkers, must be brought to justice…

The general public wants to be told how problematic pigs can pass a series of tests before they are butchered and how the meat containing harmful substances can go through a series of tests and still end up in the mouths of consumers.They also want to know whether the culprits, including pig raisers who have fed pigs harmful chemicals and those who took money to turn a blind eye to the problematic pigs and meat will get the punishments they deserve.

This isn’t the first time clenbuterol has been found in pork in China. In 2009, 70 people in Guangdong province were hospitalized for stimulant poisoning after eating organ meats from contaminated pigs; in 2006, more than 300 people in Shanghai were sickened. In January, two months before this scandal surfaced, the AP’s Alexa Olesen wrote a prescient long takeout on the complexity of controlling clenbuterol abuse, especially in rural areas.

Here’s a question: Activism for safe food in the United States was arguably ignited by Upton Sinclair’s The Jungle, a novel that served as an expose of the contamination and filthy conditions he witnessed working undercover in Chicago’s meatpacking plants. There was such a public outcry at his revelations that the Pure Food and Drug Act of 1906, the first US food-safety legislation, was written and passed in the same year the book came out. The Jungle was so influential that, 105 years later, it is still in print.

I wonder: Who will write a Jungle for China? And given the repression that seems to be practiced against whistleblowers there, if anyone did, would it see print?

Flickr/JulianPTan/CC

Diseases and borders: Potatoes and St. Patrick's Day

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Beannachtai lá le Pádraig, constant readers — or, for you English-speaking lot, Happy St. Patrick’s Day.

In Irish, the way to say “Once upon a time” is O fadó fadó — “Long, long ago…” So, for St. Patrick’s Day, an Irish story:

Long, long ago — or, by the calendar, in 1824 — the territory know as Peru broke Spain’s last hold on the New World. The nascent Republic needed trade relationships, and quickly: It had borrowed heavily from banks in Europe to finance its 3-year war of independence. But after 300 years of colonization, all it had to offer, bluntly, was crap.

No, really, crap. Bat and seabird crap, otherwise known as guano. In the centuries before the establishment of the chemical industry, guano was a precious commodity, a potent natural fertilizer packed with nitrate and phosphates. There were enormous deposits of guano on the Andean coast and offshore islands; they provided the currency that Peru’s new government leveraged into a web of trade relationships with England, the United States, and France. Guano quickly became Peru’s leading export and the basis of its entire economy. In 1841, the government nationalized the guano deposits, selling the stuff to its European and American partners in hundreds of shiploads — tens of thousands of tons — per year. [Read more…]

Drug-Resistant Bacteria: To Humans From Farms via Food

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You have to love a scientific commentary that starts this in-your-face:

“Show us the science that use of antibiotics in animal production is causing this antibiotic resistance,” Dave Warner of the National Pork Council told the Washington Post back in June 2010, responding to a Food and Drug Administration (FDA) guidance document advising against the sub-therapeutic use of antibiotics in livestock.

Well, here’s some.

To be clear: That’s the paper’s language, not mine. The gut-punch challenge comes from an editorial that is only on the web so far but is scheduled for publication in the journal Clinical Microbiology and Infection. It accompanies a research article that makes an important claim:

Chickens, chicken meat and humans in the Netherlands are carrying identical, highly drug-resistant E. coli — resistance that is apparently moving from poultry raised with antibiotics, to humans, via food. [Read more…]

Ag antibiotic use: Risky — but also sloppy and wasteful

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So, antibiotics. Given to farm animals. (Yeah, that again.) How does that work, anyway? Pills? Injections? Daily massage with specially compounded creams?

Not quite. Farm animals overwhelmingly get antibiotics in their feed. (You knew that.) And a new paper in the journal Environmental Health Perspectives explains what a bad idea that is: Animals that are given “free choice medicated feeds” (FCMF, in the jargon) can overdose or under-dose themselves, leading not only to the creation of antibiotic-resistant bacteria but to the accumulation of antibiotic residues in their flesh that can persist past slaughter.

There are two issues hidden in this. The first is the practice of giving tiny doses of antibiotics as “growth promoters,”  a use that dates back to the late 1940s. Despite a fair amount of study, there are still competing explanations for how this actually works, but the results are clear: Give animals micro-doses of antibiotics, and they put on weight faster, meaning they get to market size and can be sold — and replaced by another batch to whom the same thing happens — more quickly than if the drugs were not being used. The second is using treatment-sized doses in feed to take care of any illnesses among animals, as well as to protect animals who might pick up those illnesses in the close quarters of confinement agriculture.

If you view animal raising as an industrial-style process, the equivalent of making widgets on a production line, then medicated feed appears to make economic sense, because it offers a substantial return for little forward investment of money or labor. But as this paper picks apart, medicated feeds are not the bargain they seem. [Read more…]

Food safety: Needs speed, technology — and funds

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Perhaps you remember the Great Tomato Scare of 2008.

It started in mid-May, when the New Mexico Department of Health told the Centers for Disease Control and Prevention that it had identified a  Salmonella cluster: four people who were infected with an identical, uncommon strain called Salmonella Saintpaul, and another 15 who seemed to be part of the same outbreak but whose infections hadn’t been characterized enough for authorities to be certain. Then there were cases in Texas, and then more cases in the Navaho Nation. By June 9, 2008, there were at least 150 cases nationwide; by July 1, the count was 869. By the time the outbreak ended in late August, there would be 1,499 victims — almost certainly an undercount — in 43 states. Two people died.

The outbreak was chaotic. On June 3, based on some early studies, the Food and Drug Administration warned people in New Mexico and Texas against eating certain types of raw tomatoes; on June 7, the FDA expanded the warning to nationwide. Investigators were puzzled by tomatoes causing an outbreak so early in the season, and hypothesized that they must have been grown in a warm climate area — maybe California, Florida or Mexico. Then they were troubled by how widely the outbreak spread. Because tomatoes can come from so many different places, they wondered whether the source of the contamination wasn’t the growing fields, but rather a packing house or a wholesaler where fruit from many different farms came together.

Consumers were just as confused. The FDA said raw red plum, red Roma and red round tomatoes were no-gos, but cherry tomatoes, grape tomatoes and tomatoes sold on the vine were OK. People were unsure what was safe to eat and from where it was safe to buy. The entire enormous tomato industry — 8 billion pounds per year in the US — ground to a halt.

There was just one problem: The cause of the outbreak wasn’t tomatoes at all. [Read more…]

News break: Slaughter will reintroduce PAMTA (and cites data from this blog)

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Rep. Louise Slaughter (D-NY), Congress’s only microbiologist, said late today that she plans shortly to reintroduce PAMTA, the Preservation of Antibiotics for Medical Treatment Act, a timely move given the collapsing antibiotic market (see this morning’s post) and continuing reports of resistance moving off farms (as in this post).

PAMTA would direct the FDA to re-examine its approvals of veterinary antibiotics that are close analogs of ones used in humans, because they can stimulate the development of resistant organisms. When those organisms move off the farm, as research shows they do, they then cause illnesses that cannot be treated by the functionally identical human drugs.

The Union of Concerned Scientists said in 2008 about an earlier version of the bill:

The FDA is aware of the problem of antibiotic resistance due to overuse in animal agriculture, but the agency’s process for reviewing and withdrawing drugs from the market is far too slow and cumbersome. A recent effort to withdraw an antibiotic from use by poultry producers due to concerns about human antibiotic resistance lasted for more than five years, costing millions of taxpayer dollars. And while the judicial proceedings dragged on, disease-causing bacteria continued to outwit antibiotics.

While some producers and retailers of meat products have announced policies that take steps to curb antibiotic use, private-sector initiatives to reduce antibiotic use in animal agriculture are relatively rare, limited in scope, and difficult to verify. Federal action is needed to achieve comprehensive reductions and create a level playing field for all producers and retailers.

Passage of PAMTA is critical to keep antibiotics working for human health. In addition to averting the harmful effects of antibiotic overuse on human health, curtailing animal use of antibiotics will encourage producers to raise animals in better living conditions that are less conducive to disease.

Parenthetically, it is flattering to see Slaughter reference new data on the amount of antibiotics used in animals in the United States — almost 29 million pounds — and the percentage of the total market antibiotic market that represents: 80 percent. Those pieces of news were broken over the Congressional break by myself, here at SUPERBUG, and by Ralph Loglisci at the blog of the Center for a Livable Future.

Flickr/net_efekt/CC

Giant pig farms: Antibiotic resistance is not the only problem

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When I talk about farming, I usually focus on antibiotic over-use and the way that it stimulates the emergence of drug-resistant organisms. That’s part of what my recent book is about, and to me, it’s the critical piece in the entire discussion of industrial-scale agriculture. If we didn’t use antibiotics in such vast quantities, confined animal-feeding operations, CAFOS, couldn’t exist: Animals couldn’t survive in those conditions without them.

But so many other negatives come from CAFOs — not just antibiotic resistance, but air and water contamination, and chronic human diseases caused by effluent and pollution. I’m grateful to be reminded of that via a webinar hosted this afternoon by the Institute for Agriculture and Trade Policy, which threw a sharp light on the impact of industrial-scale hog farming in North Carolina.

The webinar took a close look at new research by University of North Carolina associate professor Steven Wing. His paper, just published on the website of the journal Epidemiology, details the acute physical symptoms experienced by North Carolina residents who live in areas near very large hog farms: eye irritation, wheezing, chest tightness, shortness of breath, sore throat and nausea.

Emerging from the farms, Wing said, are “dust, and particles from dried feces, as well as spraying of waste that aerosolizes that material. There are several important gases such as ammonia and hydrogen sulfide… as well as bioaerosols, which include endotoxin from dead bacteria. Some of these materials… are allergenic and can cause respiratory problems.”

(See Wing’s image above of manure spraying, and dead-pig disposal, outside a North Carolina hog farm.)

To get that data, Wing and colleagues at UNC and Mount Sinai School of Medicine collaborated with residents of eastern North Carolina, especially the Concerned Citizens of Tillery, in a project dubbed Community Health Effects of Industrial Hog Operations (CHIEHO). They recruited 101 adults in 16 communities who agreed to sit outside for 10 minutes twice a day, every day for two weeks, and to log their symptoms and also measure their lung function with a flow meter. Separately, the team measured ambient air pollution with continuous monitors that were parked in each community.

Overall, between September 2003 and 2005, they received 2,900 responses about people’s symptoms in the previous 12 hours, 2,600 about symptoms that were provoked by those episodes of sitting outdoors, and 1,900 error-free measurements of lung function. And — no surprise for anyone who knows what these farms look like and smell like — the symptoms tracked with the air pollution measurements.

Wing asked: “Is it fair to tell anyone they can’t go outside their own home because it is too polluted to be there?”

Here’s why conditions outside those eastern North Carolina houses are so bad. Within two miles of each of the communities that contributed to the research, there was an average of 42,000 hogs. Within North Carolina as a whole, there are more than 10 million hogs on more than 2,400 farms. The distribution looks like this:

The spots where the dots cluster most densely are Duplin and Sampson counties. Duplin contains 45 hogs for every resident; Sampson, 32. Something else those areas have in common, mentioned during the webinar by Naeema Muhammad, from Concerned Citizens of Tillery:

Most of those operations are in eastern North Carolina, and eastern North Carolina is where you have your predominantly African-American communities, …other communities of color and also your highest rates of poverty. Looking at that map, we are able to use the phrase “environmental racism.”

Wing and colleagues add in their paper:

…in low-income communities of color… there is more potential for exposure to outdoor air pollutants due to older homes that are not air tight and have no air conditioning. Many residents also lack the financial resources to travel and choose activities that could help them avoid high pollution. Exposure to air pollution from hog operations is an environmental injustice in rural areas hosting facilities that supply pork to populations spared the burdens of its production.

IATP said today they will subsequently post a recording of the webinar along with its slides; I’ll update when it goes live.

Cite: Schinasi, L et al. Air Pollution, Lung Function, and Physical Symptoms in Communities Near Concentrated Swine Feeding Operations. Epidemiology 2011;22: 208–215. DOI: 10.1097/EDE.0b013e3182093c8b

Images: Dead pigs and manure spraying at a North Carolina farm/Institute for Agriculture and Trade Policy + S. Wing, UNC; map of North Carolina hogs farms/IATP + S. Wing, UNC (adapted from Wing et al. 2001)