Occurrence and Environmental Fate of Veterinary Antibiotics in the Terrestrial Environment

Abstract

A wide variety of veterinary antibiotics (VAs) has been detected in environmental water samples, and this is of potential environmental concern due to their adverse effects. In particular, the potential for development of antibiotic-resistant bacteria has raised social concerns leading to intensive investigation regarding the influence of antibiotics on human and ecosystem health. One of the main sources of antibiotic effluence to the environment is livestock manures that often contain elevated levels of VAs that survive normal digestive procedures following medication in animal husbandry because unlike human waste, waste generated on farms does not undergo tertiary wastewater treatment, and consequently, the concentration of antibiotics entering the environment is expected to be larger from farming practices. Animal feed is often supplemented with VAs to promote growth and parasite resistance in the medicated animals, and this practice typically resulted in higher use of VAs and consequential excretion from livestock through urine and feces. The excretion rate varied depending on the type of VA used with around 75, 90, and 50-100% being excreted for chlortetracycline, sulfamethazine, and tyolsin, respectively. The excreted VAs that initially present in livestock manures were degraded more than 90% when proper composting practice was used, and hence, this can be employed as a management strategy to decrease VA environmental loads. The reduction of VA concentrations during composting was mainly attributed to abiotic processes rather than biotic degradation. The VAs released to soils by the application of manure and manure-based composts can be degraded or inactivated to various degrees through abiotic process such as adsorption to soil components. Depending on the antibiotic species and soil properties, residues can be transferred to groundwater and surface water through leaching and runoff and can potentially be taken up by plants.

Review of risk from potential emerging contaminants in UK groundwater

“…The use of veterinary antibiotics in concentrated animal feeding operations is an important source of environmental contamination in the USA and parts of Europe and Asia (BarteltHunt et al, 2010). Veterinary antibiotics have been investigated in various environmental compartments including waste lagoons, groundwater below lagoons, as well as shallow groundwater from areas where animal waste had been applied to fields (Bartelt-Hunt et al, 2010;Hu et al, 2010;Kim et al, 2011;Kolodziej et al, 2004;Sarmah et al, 2006;Watanabe et al, 2010;Watanabe et al, 2008).…”

Sorption of Sulfachloropyridazine in Brazilian Soils

“…40 Recent studies have shown that the dissipation in the environment of organic contaminants such as veterinary antibiotics can occurred via abiotic and biotic processes. 41,42 Nevertheless, several studies also revealed the presence of numerous veterinary antibiotic residue classes in surface waters and ground waters close to agricultural areas. 41,43,44 The analysis of 39 groundwater samples taken in seven different groundwater bodies of Catalonia under a relevant agricultural pressure revealed the presence of at least 15 different sulfonamides in concentration up to 274 ng L -1 , but SCP was not determined.…”

Use patterns, excretion masses and contamination profiles of antibiotics in a typical swine farm, south China

“…5 Following administration, a substantial amount of veterinary antibiotics is excreted by animals in their original form or as both active and inactive metabolites, ranging from a small proportion to about 100%. 6,7 Moreover, the inactive metabolites can potentially be transformed back into the bioactive parent compound aer excretion. For instance, N-4-acetylanted sulfamethazine was excreted as the sulfamethazine metabolite from pigs, and this compound was converted back to the parent form in liquid manure.…”