Is Free-Range Pork Really Riskier?
Photo by jere-me/FlickrCC
Curator's note: Like pretty much every advocate of sustainable agriculture, including our own Bill and Nicolette Hahn Niman, I took immediate and sharp notice of James McWilliams's New York Times op-ed suggesting that pigs raised in the very epitome of evil, pig concentration camps, might have fewer pathogenic diseases consumers need to worry about. And got worried about the possible setback to the remarkable work of Iowa pig farmers, including the original leader of Niman Ranch pork, Paul Willis, that I witnessed first hand a few years ago and wrote a pretty rhapsodic Atlantic column about. First things first: I strongly support sustainable agriculture. I've never been in contact with anyone from the pork industry. I'm not a hired bullhorn for mass-produced animal flesh (even if I am from Texas). I don't even eat meat. More important, I believe that alternative agricultural systems must always remain open to scrutiny. Just because a small, sustainable farm operates outside the realm of conventional agriculture does not mean it's flawless. Agriculture, by definition, is flawed. I thus believe in frequent and intense self-examination. It's healthy, and sometimes, when done properly, even feels good.
As anyone reading this knows, I've endured a wallop of criticism over my piece on free-range pork in last Friday's New York Times. The condemnation scans the spectrum of civility. A butcher in Iowa has offered to remove my testicles. Marion Nestle, as well as a host of other smart writers, have not. But they have legitimately questioned why I did not do two things in my Times piece: a) reveal that the study I quoted, headed by Wondwossen Gebreyes of Ohio State, was funded with a grant from the National Pork Board, and b) claim that the pigs in the study tested positive for trichinella, salmonella, and toxoplasma--when in fact they tested seropositive for these diseases. I'd like to briefly respond.
Would a handful of credentialed scientists, the board of a respected journal, and a host of outside peer reviewers engage in a grand conspiracy?
The first criticism is a red herring. In the course of writing a book on the history of insecticides, I learned that it's very difficult for scientists to undertake large studies without industry funding. You think their universities are funding them? Not likely. Why do you think so many university scientists bail out of academia and go to the dark side of Monsanto and BASF? Money. Scientists, many of them reluctantly, depend on industry to carry out basic experimentation. Fortunately, this relationship is not inherently corrupt. Industries frequently end up supporting studies that do not present the results they desire. These results still get published (and the scientists, in turn, often lose their funding). Being fully aware of the realities of scientific funding, I chose not to cite the Pork Board, but the journal in which the Gebreyes study was published. Foodborne Pathogens and Disease is a prestigious peer reviewed journal. The scientists who undertook the study are well respected researchers in veterinary medicine working at top universities. These factors assured me that any undue pressure from the funding source would have been negated.
My critics, however, fingered the pork industry's involvement from the start as ipso facto evidence of the study's lack of credibility. Do they do the same when studies funded by the Organic Farming Research Foundation highlight the benefits of organic food? Think about it. Would a handful of credentialed scientists, the board of a respected journal, and a host of outside peer reviewers engage in a grand conspiracy to twist the results of a major study that only indirectly made CAFOs (concentrated animal feeding operations) look like a preferred option? On the flip side, I know full well that if I mentioned in my lede the fact that the study was funded by the Powerful Pork People, a large portion of my readership would roll their eyes, pour another cup of Fair Trade coffee, and dig the Thursday Style section out of the recycling bin. And this is the last thing I wanted, given that these readers are the food world's movers and shakers--the very people I believe should take heed of the study and think seriously about the unintended consequences of producing food in the gray zone between the wild and domesticated. (Okay, I'm not sold on Fair Trade coffee or the Style section either--but these are fights we can have later).
The second criticism--the seropositivity matter--is more serious. I'll admit I may have erred here. May. I know full well the difference between testing positive for a pathogen and testing positive for the antibodies of that pathogen. You can test positive for the antibodies of a disease and still not have it. It's very unlikely, but possible. Faced with the choice of spending a couple of paragraphs qualifying this distinction for lay readers, I looked to see how other reports of the study dealt with the matter. At this point I was thinking not like a scientist but a writer. I wanted to keep the piece flowing without getting bogged down in the distracting minutiae of seroprevalence. The Ohio State University research summary of the article put it this way:
A comparison of swine raised in antibiotic-free and conventional pork production settings revealed that pigs raised outdoors without antibiotics had higher rates of three food-borne pathogens than did pigs on conventional farms, which remain indoors and receive preventive doses of antimicrobial drugs.
It decided not to make the distinction. The very scientific study I wrote about put it this way:
The results from this preliminary study suggest that all three pathogens were more commonly present in pigs that were reared in an ABF, outdoor, niche-market type of environment than the conventional, indoor-reared herds.
The New Scientist, summarizing the results of the study, did make the antibody distinction, but then explained that antibodies were "tell-tale signs of infection."
Absorbing these analyses, I reminded myself of what I thought to be the ultimate point in the first place: whether tested for the disease directly or for antibodies of the disease, the pigs in the study were more likely to be infected than the conventional pigs. At this point, I chose to write that the pigs had these diseases. While this decision, made in the interest of readability, hardly makes me an apologist for CAFOs, I can fully understand why readers might have preferred a more technically accurate description--even if it does not alter the underlying point of my argument.
I hope my critics are willing to meet me halfway. Even granting my potential translation errors, does it make sense to kill the messenger before exploring the full implications of the message? I'm genuinely distressed that not a single high-profile food writer has said, "hey, I have problems with this McWilliams piece, but what if it's right?"
Sustainable agriculture already has enough preachers preaching to the choir. I--a supporter of sustainable agriculture--could be one of them. But every movement must challenge its own orthodoxies. Those of us willing to do so must be assured that we won't be burned at the stake for asking tough questions that will only make our shared quest for sustainable agriculture stronger.
The op-ed raised several questions, some of which Marion Nestle asked right away, others that numerous blogs asked as well.
McWilliams is a friend, and someone I value highly as an original thinker who wants to challenge our most cherished beliefs. And, as he makes clear in the reply I asked him to give us, he shares those beliefs too! He'll also be an occasional contributor to this site, including a provocative piece--one that will rouse the very people aroused by his recent op-ed--that will appear soon. Here's his unscheduled debut. I'm glad to have it.