Review of Antimicrobial Resistance in the Environment and Its Relevance to Environmental Regulators

Abstract

The environment is increasingly being recognized for the role it might play in the global spread of clinically relevant antibiotic resistance. Environmental regulators monitor and control many of the pathways responsible for the release of resistance-driving chemicals into the environment (e.g., antimicrobials, metals, and biocides). Hence, environmental regulators should be contributing significantly to the development of global and national antimicrobial resistance (AMR) action plans. It is argued that the lack of environment-facing mitigation actions included in existing AMR action plans is likely a function of our poor fundamental understanding of many of the key issues. Here, we aim to present the problem with AMR in the environment through the lens of an environmental regulator, using the Environment Agency (England’s regulator) as an example from which parallels can be drawn globally. The issues that are pertinent to environmental regulators are drawn out to answer: What are the drivers and pathways of AMR? How do these relate to the normal work, powers and duties of environmental regulators? What are the knowledge gaps that hinder the delivery of environmental protection from AMR? We offer several thought experiments for how different mitigation strategies might proceed. We conclude that: (1) AMR Action Plans do not tackle all the potentially relevant pathways and drivers of AMR in the environment; and (2) AMR Action Plans are deficient partly because the science to inform policy is lacking and this needs to be addressed.

Quaternary ammonium compounds in soil: implications for antibiotic resistance development

“…There is growing evidence that the use of QAACs as biocides against microorganisms can lead not only to reduced biocide effectiveness, but also increase the resistance towards antibiotic agents over time (Weber and Rutala 2006;European Commission 2009;Andersson and Hughes 2012;Singer et al 2016). This can, for example, be caused by an increased expression of energy-driven drug efflux systems such as the AcrAB pump or the NorA and MdeA multidrug efflux systems that can extrude QACs as well as multiple antibiotics (Levy 2002;Poole 2005;Hegstad et al 2010b).…”

What are the effective solutions to control the dissemination of antibiotic resistance in the environment? A systematic review protocol

“…These treatments can contribute to decrease the concentrations of antibiotic residues and other pollutants by degradation (biotic or abiotic), dilution and/or bound residues formation [4,11], and also to decrease the levels of ARB and ARGs [12]. Persistent antibiotic residues can be preferentially sorbed into the sludge; this suggests different risks between sludge application on agricultural soils and discharge of sewage effluent into aquatic environment [13]. The waste management can contribute to minimize the dissemination of antibiotic resistance before their discharge in the natural compartments [14], e.g., treated wastewater in the aquatic environment, sludge or livestock manure in agricultural soil [13,15].…”

“…Persistent antibiotic residues can be preferentially sorbed into the sludge; this suggests different risks between sludge application on agricultural soils and discharge of sewage effluent into aquatic environment [13]. The waste management can contribute to minimize the dissemination of antibiotic resistance before their discharge in the natural compartments [14], e.g., treated wastewater in the aquatic environment, sludge or livestock manure in agricultural soil [13,15]. Diffuse sources such as surface runoff, leaching, could also be considered in the dissemination of antibiotic resistance in the environment [16,17].…”

“…Anthropogenic activities largely contribute to the enrichment of the resistome of different ecosystems: the aquatic and terrestrial environments, also the atmosphere (aerosols, particles, dust) and the wildlife; exposing the bacteria, humans and animals to ARB and ARGs [13,18,[21][22][23][24][25]. As a serious concern, the environmental reservoirs are a source of emergence and transfer of ARGs from environmental to introduced bacteria into those pathogenic to humans and animals [26,27].…”

“…Consequently, the environmental contamination by antibiotic resistance is potentially associated with impacts on human and animal health. Nowadays, the worldwide presence of ARB and ARGs due to antibiotic misuse and overuse in agricultural and healthcare sectors threatens the efficacy of existing and future antibiotics [13,28].…”