Treatment of Antibiotics and Antibiotic Resistant Bacteria in Swine Wastewater with Free Chlorine

Abstract

Recent recognition of the occurrence of antibiotics in the environment has highlighted concerns regarding potential threats of antibiotics to humans and wildlife. Antibiotics are commonly applied to animals to prevent diseases and promote growth, making livestock agriculture a major source of antibiotic pollution. The purpose of our study was to examine chlorination technology as a method for preventing the release of antibiotics as well as antibiotic-resistant bacteria into the environment from concentrated animal feeding operations. Wastewaters from various sites of two anaerobic lagoon systems, one aerated and the other not, on a swine facility were investigated. Each system consisted of a primary treatment lagoon and a subsequent polishing lagoon. Free chlorine (or monochloramine for comparison) was applied to oxidize antibiotics and to disinfect lagoon bacteria as well. Results indicate that aeration substantially improves lagoon functionality, thereby adding both organic and ammonia removal. Ammonia present in the wastewaters plays a critical role in antibiotics decomposition and bacterial inactivation due to its rapid competition for free chlorine to form monochloramine. Generally, a chlorine dose close to breakpoint is required to achieve complete removal of antibiotics, leading to high consumption of free chlorine in most of the wastewaters examined. However, because of a low ammonia concentration in the polishing lagoon wastewater of the aerated system, a chlorine dose of 100 mg/L can effectively achieve complete removal of both antibiotics and bacteria. On the basis of our experimental findings, a possible strategy for the treatment of swine wastewater is suggested.

Degradation of methiocarb by monochloramine in water treatment: Kinetics and pathways

“…NH 2 Cl was freshly prepared by mixing NaOCl and NH 4 Cl solutions at a Cl 2 :N molar ratio of 0.8 at about pH 10 except otherwise stated. NH 4 Cl was purposely applied in excess to achieve a 100% yield of NH 2 Cl and suppress the spontaneous decomposition of the formed NH 2 Cl as well (Qiang and Adams, 2004). All reaction solutions were prepared with ultrapure water produced by a Milli-Q system (Advantage A10, Millipore) and buffered with 10 mM phosphate in the pH range of 6.1e8.9.…”

“…Chamberlain and Adams, 2006;Qiang et al, 2006;Rodríguez et al, 2007). The degree of NH 2 Cl hydrolysis increases with a decrease in the solution pH (Morris and Issac, 1983).…”

Treatment options for wastewater effluents from pharmaceutical companies

“…Chlorination has been shown to be effective for the removal of pharmaceuticals including 17α-ethinylestradiol and 17 β-estradiol (Alum et al, 2004) and sulfonamides (Qiang et al, 2006). Chlorine dioxide is also effective for the removal of sulfamethoxazole, roxithromycin, 17α-ethinylestradiol and diclofenac (Khetan and Collins, 2007).…”

Removal of veterinary antibiotics from sequencing batch reactor (SBR) pretreated swine wastewater by Fenton's reagent

“…Increasing Fenton's reagent dosage resulted in a significant increase in disinfection efficiency. It is seen that Fenton's reagent is also quite effective in inactivating bacteria, which is somewhat comparable to ozonation and chlorination Qiang et al, 2006). Because it was difficult to identify the degradation byproducts of antibiotics in the complex matrix of SBR effluent which also contained a variety of background organic substances, the acute toxicity of reaction solution was measured instead.…”