Pick your (bug) poison

Humankind’s never-ending battle against pestilence has produced yet another unintended consequence: proteins from genetically altered crops in surface water.

A study conducted by the University of Notre Dame and Loyola University looked at 217 streams, drains and ditches near Indiana cornfields and found the bug-killing protein in 50 of them at rates above the detectable level of six nanograms per liter. The protein is carried to surface water by runoff and by the leaves and stalks that sometimes wash into streams. And the protein lingers. The study was conducted six months after harvest.

An article about the study is here.

The protein is taken from a soil bacteria and inserted in corn to kill the European corn borer. When the insects chomp on the corn plants, presto, they die—no environmentally unfriendly pesticides needed. Farmers have received the science so enthusiastically that the seeds were used for 85 percent of the U.S. corn crop last year. Mycogen, the brand owned by Indianapolis-based Dow AgroSciences, is just one company pitching the product.

The paper, published in the Proceedings of the National Academy of Sciences, says it is not known whether the trace levels of the protein are a threat to invertebrates in the water.

Farmers are having a hard time winning. Traditional pesticides kept finding their way into water, and now it’s apparent that poison from genetically modified crops is, too.

A related dilemma raised in the study is the ways farmers till, or don’t till, the soil. Farmers minimized tillage to save money and to leave crop residue on the surface where it can keep soil and chemicals from washing into streams. But the residue is now leaching the bug-killing proteins into water.

If bug control is coming down to the least of available evils, which poison do you pick?