Fears Grow After Biblical Dust Storm Blankets American South

http://www.whatdoesitmean.com/index1617.htm

“All civilization rests on an inch of topsoil.  That's where all our food and fiber comes from.  So when that's gone, it's gone.  Some of that soil started to form when Alexander the Great was a baby, so if you lose it, you're not getting it back,” 

U.S. Drought 2012: Pick Your Poison

http://www.scientificamerican.com/article.cfm?id=us-drought-2012-pick-your-poison

For humans, nitrate brings two main health issues: blue baby syndrome and digestive tract cancers [pdf]. 

But the danger to humans is through drinking water. Nitrogen fertilizer not sucked up by plants often washes into streams and lakes. This summer's dryness has sent less nitrogen-laced runoff into Midwest streams, Ensley said.