Fates of antibiotic resistance genes in a distributed swine wastewater treatment plant

Abstract

This study explores the prevalence, emission, and reduction of five ARGs (sulI, tetA, mphB, qnrD, and mcr‐1) and integron (intI) through a distributed swine wastewater purification facility and the effluent‐receiving environment. Typical metal resistance genes (MRGs), pathogenic bacterial indicators, the bacterial community, and wastewater properties were also explored to determine their effects on the fates of ARGs. Results indicated that the purification process could hardly effectively remove ARGs’ prevalence. 3.1 × 104–7.1 × 108 copies/L were present after purification, and 4%–57% of them persisted in the subsequent creek and adjacent soil. 16S rRNA sequencing suggested that the discharge of wastewater significantly changed the bacterial community in receiving creek and soil. Molecular ecological networks analysis detected the wide co‐occurrence among ARGs, MRGs, and PBGs, which could further facilitate the propagation of antibiotic resistance. ARG incidence and specific bacterial genera were closely correlated, suggesting an extensive hosting relationship. Redundancy analyses showed wastewater organics and nutrients showed positive correlation to most ARGs’ abundance, but negatively correlated to their relative abundance. Practitioner points Fate of five ARGs and intI was studied in a swine wastewater treatment system. The treatment process could not effectively reduce ARGs’ abundance. ARGs and pathogens in wastewater were transferred to the receiving creek and soil. The network analysis found wide co‐occurrence among ARGs, metal resistance genes, and pathogens. Wastewater nutrients positively correlated to ARG's abundance but negatively correlated to their relative abundance.

Swine liquid manure: a hotspot of mobile genetic elements and antibiotic resistance genes

“…4 and 5 ), demonstrating the high prevalence of ARGs and their host microbes in the two swine farms. Moreover, numerous studies also implied that swine liquid manure is a huge reservoir of ARGs 12 , 49 , 58 – 60 . Among these investigated ARGs, the levels of tet -ARGs ( tet O, tet W and tet Q) were found to be the highest, ranging from (2.04 ± 0.35) × 10 8 to (2.14 ± 0.21) × 10 11 copies/g dry weight (DW) in pig feces in both swine farms, followed by sul -ARGs ( sul 1 and sul 2) with a concentration range from (1.14 ± 0.13) × 10 6 to (9.61 ± 0.59) × 10 11 copies/g DW.…”

Massive analysis of 64’628 bacterial genomes to decipher a water reservoir and origin of mobile colistin resistance (mcr) gene variants: is there another role for this family of enzymes?

“…Indeed, almost all MCR variants described so far have been reported from bacteria from water in different environments. MCR-1 was detected and identified directly from swine wastewater of purification facilities 35,36 , directly from water or from bacteria (e.g. E. coli and E. cloacae ) collected from urban surface water, rivers or lakes 37–39 .…”

Upcycling of manure with insects: current and future prospects

“…Often, antibiotic residues have been detected at levels much higher (as much as 28,000 times) than in background soil or water (Chee-Sanford et al, 2009;Sim et al, 2011). And, though the abundance of antibiotic residues in livestock waste varies among livestock farm types, and regional regulations, the most frequently detected antibiotic residues include those from the fluoroquinolone, sulphonamide, and tetracycline drug classes, though other classes such as trimethroprim and macrolides have also been detected (Chee-Sanford et al, 2009;Prosser and Sibley, 2015;Wallace et al, 2018;Yuan et al, 2019). While further research needs to be conducted to determine the full impact on human, animal, and ecosystem health, there is general agreement within public and private entities that mitigation strategies should be implemented to prolong the effectiveness of currently used antibiotics while lessening the dissemination of antibiotic resistant bacteria and genes (Carbajal et al, 2017;CDC, 2015;EU, 2016;World Health Organization, 2015) A recent and exciting finding is the black soldier fly larvaemediated degradation of pharmaceuticals.…”