The Iraqi invasion of Kuwait in 1991, and the ensuing Persian Gulf War, left behind half a million unexploded land mines. Today, Explosive Ordnance Disposal teams are still working to clear out those mines.
Less critical, but still a serious health concern, is the residue left from exploded ordnance. Soil across Kuwait is contaminated with TNT and other explosive compounds. If inhaled in dust, or ingested through ground water, TNT residue can cause dermatitis, kidney disease, anemia, and even cancer. Traditional soil cleaning methods like incineration are expensive and mar the environment. OSU Professor Morrie Craig has a better idea: Send out the sheep.
As a toxicologist in the College of Veterinary Medicine, Craig discovered that the multiple stomach chambers in a sheep contain bacteria that break down alkaloid toxins in plants. This makes it possible for them to eat all kinds of nasty weeds that make other animals sick.
When the U.S. military heard about his research, they suggested Craig test sheep bacteria on a synthetic alkaloid toxin: TNT. Used in the manufacture of bombs for the U.S. military since World War II, the military was looking for cost-effective ways to clean up TNT-contaminated sites in the U.S. and around the world.
In 2011, Craig and researchers from the U.S. Department of Agriculture fed sheep TNT for three weeks and found that it broke down in the sheep’s stomach so completely there was no trace of it in their feces. When coupled with Craig’s earlier research on the use of grasses to suck contaminants out of the soil, these new findings gave Craig a plan for bioremediation of explosives residue: Plant grass in contaminated areas then graze sheep on those fields.
After testing his plan on soil at a military base, Craig estimates a flock of 20 sheep can completely clear an acre of explosives residue in less than three years. Now he is working with the Kuwaiti government to help them adapt his discoveries to a plan that will work in their country. They are currently testing warm-season grasses for TNT uptake, and they are investigating the possibility of using camels as well as sheep. Funding for the projects comes from a tax on Iraqi oil as part of a United Nations settlement to compensate Kuwait for damage done by the Persian Gulf War.
In December, Dr. Craig will be the keynote speaker at an international seminar in Kuwait on The Environmental Impact of Explosive Remnants of War.
