Potential of Biological Processes to Eliminate Antibiotics in Livestock Manure: An Overview

Abstract

Simple SummaryBeside their use to treat infections, antibiotics are used excessively as growth promoting factors in livestock industry. Animals discharge in their feces and urine between 70%–90% of the antibiotic administrated unchanged or in active metabolites. Because livestock manure is re-applied to land as a fertilizer, concerns are growing over spread of antibiotics in water and soil. Development of antibiotic resistant bacteria is a major risk. This paper reviewed the potential of anaerobic digestion to degrade antibiotics in livestock manure. Anaerobic digestion can degrade manure-laden antibiotic to various extents depending on the concentration and class of antibiotic, bioreactor operating conditions, type of feedstock and inoculum sources.AbstractDegrading antibiotics discharged in the livestock manure in a well-controlled bioprocess contributes to a more sustainable and environment-friendly livestock breeding. Although most antibiotics remain stable during manure storage, anaerobic digestion can degrade and remove them to various extents depending on the concentration and class of antibiotic, bioreactor operating conditions, type of feedstock and inoculum sources. Generally, antibiotics are degraded during composting > anaerobic digestion > manure storage > soil. Manure matrix variation influences extraction, quantification, and degradation of antibiotics, but it has not been well investigated. Fractioning of manure-laden antibiotics into liquid and solid phases and its effects on their anaerobic degradation and the contribution of abiotic (physical and chemical) versus biotic degradation mechanisms need to be quantified for various manures, antibiotics types, reactor designs and temperature of operations. More research is required to determine the kinetics of antibiotics’ metabolites degradation during anaerobic digestion. Further investigations are required to assess the degradation of antibiotics during psychrophilic anaerobic digestion.

Fate of the antibiotic sulfadiazine in natural soils: Experimental and numerical investigations

“…Following the German recommendations for the best practice for manure applications to low and moderately fertile soils, it was assumed that a maximum of 10 m 3 of manure was applied per hectare. SDZ concentrations can be related to the dry matter content of manure with 51 mg SDZ per kg dry matter (Guo et al, 2012;Massé et al, 2014). Since manure may contain 10 to 20% of dry matter, a dry matter content of 20% was selected as the worst case scenario, resulting in a total SDZ concentration of 10.2 mg/m 2 per manure application.…”

Trace organic contaminants in biosolids: Impact of conventional wastewater and sludge processing technologies and emerging alternatives

“…The formation of estrogenic byproducts is consistently observed even in the anaerobic digestion of other materials than sludge (e.g. animal manure) [110][111][112].…”

“…Notably, there is similarity in the TrOC removal of composts of different materials, e.g. sludge, manure, and municipal solid waste [40,112,131]. For example, the removal of fluoroquinolones and sulfonamides from sludge (e.g.…”

Antibiotic residues and resistance in the environment

“…The highest and most frequently reported concentrations of antibiotic residues in manure belong to the tetracycline group of antibiotics. The reported levels regularly exceed 100 mg kg-1 (Massé, 2014), with extremes up to 764 mg kg-1 chlorotetracycline in swine manure (Pan, 2011). Observed concentrations for sulfonamides are also considerable: Martinez-Carballo (2007) reported concentrations level up to 20 mg kg-1 for sulfadimidine and up to 91 mg kg-1 for sulfadiazine (Martinez-Carballo, 2007).…”

“…For example, a study by showed that composting reduced the concentration of extractable tetracyclines, sulfonamides and macrolides with 96%, 99% and 95%, respectively. Anaerobic digestion has also been suggested as an effective method to degrade and remove antibiotics (Massé, 2014). The removal of antibiotics during such processes is mainly attributed to temperature dependent abiotic processes such as adsorption and degradation (Aust, 2008;Arikan, 2009).…”