http://www.nytimes.com/2012/04/26/business/energy-environment/dow-weed-killer-runs-into-opposition.html?pagewanted=1&_r=3&pagewanted=all

http://www.cbsnews.com/8301-504763_162-57423245-10391704/genetically-modified-crops-resistant-to-24-d-spur-debate-calls-for-labeling/

(sections taken from NYT article)

Dow Corn, Resistant to a Weed Killer, Runs Into Opposition (It should be opposed)

To Jody Herr, it was a telltale sign that one of his tomato fields had been poisoned by 2,4-D, the powerful herbicide that was an ingredient in Agent Orange, the Vietnam War defoliant. “The leaves had curled and the plants were kind of twisting rather than growing straight,” Mr. Herr said of the 2009 incident on his vegetable farm in Lowell, Ind. He is convinced the chemical, as well as another herbicide called dicamba, had wafted through the air from farms nearly two miles away.

Mr. Herr recalled the incident because he is concerned that the Dow Chemical company is on the verge of winning regulatory approval for corn that is genetically engineered to be immune to 2,4-D, allowing farmers to spray the chemical to kill weeds without harming the corn stalks. (Are your intestines genetically engineered to be immune to corn that is 'genetically engineered to be immune to 2,4-D'? NO! Given the sheer number of cereals, snacks, and almost anything sweet (corn syrup) that involve corn, this might be important)
...
Most experts agree that the harm from Agent Orange was caused primarily by its other ingredient, 2,4,5-T, which was taken off the market long ago. By contrast, 2,4-D, first approved in the late 1940s, is considered safe enough for use in many home lawn care products. (Show of hands, how many people eat their lawn?)
...
The activity stems from the huge success, at least initially, of Monsanto’s Roundup Ready crops, which are genetically engineered to tolerate its herbicide Roundup, also sold generically as glyphosate.

Those crops made it so easy for farmers to control weeds by spraying glyphosate that Roundup Ready crops now account for about 90 percent of soybeans and around 70 percent of the corn and cotton grown in the United States. And use of glyphosate skyrocketed, at the expense of rival herbicides.

But farmers relied too much on glyphosate, allowing weeds to develop resistance to the chemical. ('Cause no one saw that coming and raised he-- warned about it.) The problem has been worst in the South, where a particularly strong and prolific plant called Palmer amaranth, or pigweed, has overrun cotton fields, forcing many farmers to hire crews to remove weeds by hand.

Dow’s crops contain a gene from a soil bacterium that causes them to make a protein that breaks down 2,4-D into other chemicals that are not harmful to plants. (I'll get back to this, in a minute.*)

Dow and its supporters say resistance is not that likely to develop because various herbicide-tolerant crops will be competing, meaning no herbicide will be as dominant as Roundup has been. (Refer back to the section on glyphosate overuse.This time, it's different?)

*There is no mention in the articles of what happens when overspray,wind, or rain inevitably rinse some of this off the plants BEFORE they are able to absorb all of it. Multiply TIMES millions of acres. Once it hits the water table and is pulled up by well pumps and unknowingly used by cities for drinking water, or other farmers on their fields or animal feed operations, then it's in everything and everyone.

Bonus Questions:
Where does your municipality source your tap water from?
What do they do with the water you "send back" to them?