Use of Dissolved Organic Carbon to Biostimulate Rapid Rhizodegradation of Perchlorate in Soil

Contamination of freshwater resources, fresh produce and some processed foods by perchlorate (ClO4 -) is a growing problem in the United States. The anion perchlorate is a naturally occurring as well as an anthropogenic chemical which occurs as salts of ammonium, sodium and potassium. The natural sources of perchlorate include Chilean caliche which is mined for use as a natural source of NaNO3 in fertilizer and evaporite deposits in arid climates. Fertilizer manufactured from Chilean caliche may contain approximately 0.5-2 mg g-1 perchlorate [1]. The main anthropogenic source of perchlorate is ammonium perchlorate (NH4ClO4), which is used as an oxygenadding component in propellants for rockets, missiles and fireworks. Ammonium perchlorate is highly soluble in water and dissociates to ammonium (NH4 +) and perchlorate (ClO4 -) ions. Perchlorate is very stable under typical surface and ground water conditions.