WATER RESOURCES RESEARCH GRANT PROPOSAL
Project ID: 2005AR82B
Title: The distribution of roxarsone and its byproducts in soils, soil pore-water, groundwater, and stream water
Project Type: Research
Focus Categories: Hydrogeochemistry, Agriculture, Sediments
Keywords: Poultry Litter, Groundwater Quality, Arsenic
Start Date: 03/01/2004
End Date: 02/28/2005
Federal Funds: $19,460
Non-Federal Matching Funds: $40,850
Congressional District: 1
Principal Investigator:
Carolyn Dowling
Arkansas State University
Abstract
Most poultry litter from commercial poultry operations contains arsenic from the use of roxarsone, an organoarsenic feed additive. Because of the high nutrient content, poultry litter is reused as fertilizer for neighboring agricultural fields. The roxarsone in the poultry-litter fertilizer will degrade into both inorganic arsenic species [arsenite (As(III)) and arsenate (As(V))], and organic arsenic species [monomethylarsenic acid (MMA) and dimethylarseonic acid (DMA)]. The organoarsenicals (MMA and DMA) are produced by biomethylation via bacteria, fungi, and algae and are more toxic than their inorganic counterparts. Previous research indicates that the composting of poultry litter may release roxarsone and its by-products into the environment, which may impact soil and water resources from the accumulation of arsenic, other heavy metals, and nutrients over time. This investigation will characterize the mobility and concentration of roxarsone and its byproducts (inorganic and organic arsenic species) in poultry litter, soils, soil pore-water, groundwater, and streams in a small area on the Farm Complex at Arkansas State University. The transport pathway for roxarsone, As(III), As(V), MMA, and DMA in the environment will be determined. The proposed study will encourage undergraduate students at Arkansas State University to become involved in Chemistry through an undergraduate research project and will create exciting hands-on learning experiences for an undergraduate student interested in Environmental Chemistry.