by Larry Geller

At last, an explanation is in for the pig poop explosions at barns in the Midwest that have plagued commercial pig farmers. In the latest incident, 1,500 pigs died and one worker was injured in an explosion in September 2011 in a barn in Iowa.

What? You haven’t been following this story? Are you a vegetarian or something?

If not, you soon may be.

The culprit turns out to be pig poop foam, often piling up as high as four feet, and highly explosive. The foam traps methane gas, which is easily ignited by any spark.

The image of pig poop foaming up to four feet high is bad enough. Where did it come from? Do I really want to know about this?

In case you do, there is a great article in the University of Minnesota newspaper, The Minnesota Daily: Exploding hog barns beckon U researchers: A team is investigating foam that has caused Midwest swine barns to unexpectedly explode (2/7/2012).

The professors understand the problem, and they have a solution:

Not only does the foam cause explosions but it also reduces manure storage volume and dirties the hogs.



The foam can reach heights of 4 feet. Farmers are encouraged to knock it down with water.

In Minnesota, dirty hogs are apparently an issue. Spraying water probably helps with that too.

Preventing the smudging has moved the investigation into high gear:

The researchers still aren’t sure what causes the foam. But they have noticed a correlation between adding dried distillers grains in soluble — a product of the ethanol production process increasingly used in livestock diets — to the hogs’ diets and the foam, although that solution is too simplistic, Jacobson said.

This sounds very plausible. They have not gone so far as to suggest that hog farm foam might be bottled as a gasoline additive, however.

If you are on the edge of vegetarianism by now, this next article could push you over. It’s from Mother Jones: The Mystery of Exploding Pig Poop (2/9/2012).

But seriously, what gives? First, it helps to have an idea of how manure is handled at industrial hog facilities. In his classic 2005 Rolling Stone exposé of the industrial pork giant Smithfield, Jeff Tietz provided a vivid description:

The floors are slatted to allow excrement to fall into a catchment pit under the pens, but many things besides excrement can wind up in the pits: afterbirths, piglets accidentally crushed by their mothers, old batteries, broken bottles of insecticide, antibiotic syringes, stillborn pigs—anything small enough to fit through the foot-wide pipes that drain the pits. The pipes remain closed until enough sewage accumulates in the pits to create good expulsion pressure; then the pipes are opened and everything bursts out into a large holding pond.



The manure itself is pretty nasty, too. Pigs on factory farms are given daily doses of antibiotics and growth-promoting additives like ractopamine, much of which ends up in their waste. So what you get in those cesspools, the ones now exploding in the Midwest, is kind of a stew of bacteria, antibacterial agents, and novel antibiotic-resistant bacteria strains, all mixed with the random detritus described by Tietz.

Enough.

It is possible to purchase pork that does not come from these factory farms. Or, it is possible to do without. If you are not yet convinced, please check out the Mother Jones article at the link above, or the Rolling Stone article, and then see how you feel about all this.