Environmental Fate of Roxarsone in Poultry Litter. I. Degradation of Roxarsone during Composting

• Published in: Environmental science & technology Vol. 37; no. 8; pp. 1509 - 1514
• Main Authors: Garbarino, J. R, Bednar, A. J, Rutherford, D. W, Beyer, R. S, Wershaw, R. L
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.04.2003
• Subjects: Acids; Agriculture, rearing and food industries wastes; Agronomy. Soil science and plant productions; Animal Feed; Animal Husbandry; Animals; Anti-Bacterial Agents - analysis; Anti-Bacterial Agents - metabolism; Applied sciences; Arsenic; Biodegradation, Environmental; Biological and medical sciences; Biological and physicochemical properties of pollutants. Interaction in the soil; Composting; Enterobacteriaceae; Environmental impact; Environmental Monitoring; Exact sciences and technology; Fertilizers; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Manure; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; Pollution; Poultry; Refuse Disposal; roxarsone; Roxarsone - analysis; Roxarsone - metabolism; Soil and sediments pollution; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Wastes; Biodegradation; Microbial activity; Roxarsone; Arsenates; Pollutant behavior; Farmyard manure; Soil pollution; Vertebrata; Amendment; Composting; Upgrading; Environment impact; Waste reuse; Agricultural waste; Aves; Rearing by-product; Speciation
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es026219q

Roxarsone, 3-nitro-4-hydroxyphenylarsonic acid, is an organoarsenic compound that is used extensively in the feed of broiler poultry to control coccidial intestinal parasites, improve feed efficiency, and promote rapid growth. Nearly all the roxarsone in the feed is excreted unchanged in the manure. Poultry litter composed of the manure and bedding material has a high nutrient content and is used routinely as a fertilizer on cropland and pasture. Investigations were conducted to determine the fate of poultry-litter roxarsone in the environment. Experiments indicated that roxarsone was stable in fresh dried litter; the primary arsenic species extracted with water from dried litter was roxarsone. However, when water was added to litter at about 50 wt % and the mixture was allowed to compost at 40 °C, the speciation of arsenic shifted from roxarsone to primarily arsenate in about 30 days. Increasing the amount of water increased the rate of degradation. Experiments also suggested that the degradation process most likely was biotic in nature. The rate of degradation was directly proportional to the incubation temperature; heat sterilization eliminated the degradation. Biotic degradation also was supported by results from enterobacteriaceae growth media that were inoculated with litter slurry to enhance the biotic processes and to reduce the concomitant abiotic effects from the complex litter solution. Samples collected from a variety of litter windrows in Arkansas, Oklahoma, and Maryland also showed that roxarsone originally present had been converted to arsenate.