Sewage sludge as a source of triclosan-resistant bacteria

Abstract

Subinhibitory concentrations of antibiotics and biocides in wastewaters and sewage sludge have a great impact on the development of antibiotic resistance and its spread among bacteria. The aim of this work was to determine the occurrence of coliform bacteria and enterococci resistant to biocide triclosan in samples of sewage sludge. Subsequently, isolated strains of coliform bacteria were identified and characterized in terms of their antibiotic susceptibility and ability to form a biofilm. Occurrence of the studied bacteria was monitored in three samples of stabilized sludge from three different wastewater treatment plants (Vrakuňa, Petržalka, and Senec). The number of triclosan-resistant coliforms was the highest in the sludge sample from the wastewater treatment plant in Senec and the lowest in the sludge sample from the wastewater treatment plant in Petržalka. Triclosan-resistant Enterococcus spp. were not found in any sample of stabilized sludge. Most isolates were identified as Citrobacter freundii and Serratia spp. Triclosan-resistant isolates showed also resistance to antibiotics and the majority of them were strong biofilm producers.

Early Developmental Exposure to Triclosan Impacts Fecal Microbial Populations, IgA and Functional Activities of the Rat Microbiome

“…Although humans are exposed to low doses of many chemicals, their presence in surface, ground and drinking water indicates their persistence and potential accumulation in the human body at high doses [6,55,56]. TCS, previously a commonly used antimicrobial compound, has raised public concerns due to evidence that suggests its link to alteration of host physiology [51], disruption of microbial communities [9,57] and an increase in bacterial resistance [7,[58][59][60]. Moreover, TCS is also linked to induce risk among neonates via breastmilk intake [5,56,61].…”

“…Studies have shown that human skin and oral mucosa are capable of absorbing TCS, which results in the detection of TCS in various tissues and body fluids [4,5]. Consumer and commercial product wastes are known to contaminate the environment and water sources and the presence of TCS in these materials could have an adverse impact on health [6,7]. Continuous exposure to TCS through various consumer products, as well as the deposition of TCS in river water and soil, leads to the emergence of antimicrobial-resistant bacteria [8,9].…”

Extraction of iron from laterite soil and green synthesis of laterite nano iron catalyst (GLaNICs) for its application as Fenton's catalyst in the degradation of triclosan

“…Resistance to biotransformation made triclosan unsuitable for biological treatment. Lépesová & Krahulcová (2019), identified bacterial strain such as Citrobacter freundii and Serratia spp. known for its triclosan resistance in sewage sludge rendering resistance to biotransformation (Lépesová & Krahulcová 2019).…”

“…Lépesová & Krahulcová (2019), identified bacterial strain such as Citrobacter freundii and Serratia spp. known for its triclosan resistance in sewage sludge rendering resistance to biotransformation (Lépesová & Krahulcová 2019). Adsorption is known to remove triclosan effectively with its limitations in the maintenance and regeneration of adsorbent.…”