How does chemical-intensive, concentrated agriculture affect surrounding ecosystems — and ones that lie downstream from large operations?

Seems like a key question, given that upwards of 95 percent of our food comes from such agricultural methods. Yet there has been surprisingly little study of it. For example, when the meat industry started to rapidly consolidate production into large concentrated-animal feedlot operations (CAFOs) in the 1970s, government regulatory agencies made little effort to find out how it would affect surrounding communities.

So we essentially got an uncontrolled experiment –with residents of places like North Carolina’s Duplin County and Iowa’s Hardin County as conscripted subjects — on the health effects of living near massive manure "lagoons."

Another example is synthetic pesticides — one of the great innovations of monocrop agriculture. (Of course, only when a single crop is planted over a massive swath of land are powerful pesticides necessary in the first place.)

Since the publication of Rachel Carson’s Silent Spring in 1962, there has been a significant amount of work on regulating pesticides. One important bit has involved limiting the concentrations of pesticide residue that can end up in drinking water.

However, these limits involve individual pesticides in isolation. They limit, for example, how many parts per million of atrazine can end up in drinking water, and how many parts per million of endosulfan. But they don’t look at how atrazine and endosulfan, even at very low levels, interact together.

Farmers don’t always use pesticides in isolation; they often use them in combination. And Farm A may be releasing one or two pesticides into the groundwater, and Farm B down the road one or two different ones.

In other words, regulations treat pesticides in isolation, while on the ground pesticides accumulate and enter ecosystems in combination. How do these pesticide cocktails affect surrounding ecosystems and ones downstream?

Two recent studies shed light on the public-health/ecosystem affects of CAFOs and synthetic pesticides.

Researchers at the University of Pittsburgh have been studying how pesticide cocktails affect amphibian populations. The results, released recently in the journal Oecologia, aren’t encouraging. From the press release from the University of Pittsburgh:

Ten of the world’s most popular pesticides can decimate amphibian populations when mixed together even if the concentration of the individual chemicals are within limits considered safe.

The researchers selected five commonly used insecticides (carbaryl, chlorpyrifos, diazinon, endosulfan, and malathion), as well as five popular herbicides (acetochlor, atrazine, glyphosate, metolachlor, and 2,4-D). Here’s how it went:

The [researchers] found that a mixture of all 10 chemicals killed 99 percent of leopard frog tadpoles as did the insecticide-only mixture; the herbicide mixture had no effect on the tadpoles. While leopard frogs perished, gray tree frogs did not succumb to the poisons and instead flourished in the absence of leopard frog competitors.

The study provides evidence that pesticide cocktails are having a profound impact on ecosystems — snuffing some species out, providing niches for others.

On the CAFO front, Wellesley College researcher Stacy Sneeringer looked at infant mortality rates near livestock confinements, publishing her results in the American Journal of Agricultural Economics. I have a request in to receive a copy of the article.

According to the press release, "Sneeringer found a statistically strong positive relationship between livestock farming and infant mortality." She found that when livestock production doubles in a county, infant mortality rises 7.4 percent.

The press release goes on:

Most of this effect occurs within the first twenty-eight days of life. Sneeringer interprets her results as reflecting damage to the fetus, as evidenced by higher rates of neonatal infant mortality, causes of death related to problems in the perinatal period, and lowered Apgar scores. "The results of this article suggest that the mechanism by which this effect operates may be increased air pollution," Sneeringer notes.

As anyone who’s been to CAFO-dominated counties knows well, breathing the fetid air just seems profoundly unhealthy. This study provides stark evidence backing up that commonsense perception.

Both studies raise deeply troubling questions about the way we raise our food. Who and what are we willing to sacrifice in service of industrial food? Dead babies and tadpoles are proxies for ecosystems under assault from industrial poisons and toxic animal waste. We’ve only been utilizing huge amounts of pesticides for about 50 years, and CAFOs for 30. We may only be beginning to learn the full extant of our sacrifices.

Just as I prepared to post this, another article crossed my desk, this one from the Fresno Bee. In a nutshell:

For years, researchers have suspected commercial pesticides put people at risk for Parkinson’s disease. Now evidence in the San Joaquin Valley suggests it’s true. Researchers have found a strong connection between the debilitating neurological disease and long-term exposure to pesticides, particularly to a fungicide that is sprayed on thousands of acres of almonds, tree fruit and grapes in the Valley.