Microbiological safety and antibiotic resistance risks at a sustainable farm under large-scale open-air composting and composting toilet systems

Potential of combined reactor and static composting applications for the removal of heavy metals and antibiotic resistance genes from chicken manure

Chicken manure (CM) can pose a serious threat to environmental and human health, and need to be managed properly. The compost can effectively treat CM. However, there is limited research on the heavy metals and antibiotic resistance genes (ARGs) during compost CM. In this study, the combined application of reactor and static composting (RSC) was used to produce organic fertilizer of CM (OCM), and heavy metals, ARGs and bacterial community structure was investigated. The results show that RSC could be used to produce OCM, and OCM meet the National organic fertilizer standard (NY/T525-2021). Compared to the initial CM, DTPA-Cu, DTPA-Zn, DTPA-Pb, DTPA-Cr, DTPA-Ni and DTPA-As in OCM decreased by 40.83%, 23.73%, 34.27%, 38.62%, 16.26%, and 43.35%, respectively. RSC decreased the relative abundance of ARGs in CM by 84.06%, while the relative abundance of sul1 and ermC increased. In addition, the relative abundance and diversity of ARGs were mainly influenced by the bacterial community, with Actinobacteria, Firmicutes, and Proteobacteria becoming the dominant phyla during composting, and probably being the main carriers and dispersers of most of the ARGs. Network analyses confirmed that Gracilibacillus, Lactobacillus, Nocardiopsis, Mesorhizobium and Salinicoccus were the main potential hosts of ARGs, with the main potential hosts of sul1 and ermC being Mesorhizobium and Salinicoccus. The passivation and physicochemical properties of heavy metals contribute to the removal of ARGs, with sul1 and ermC being affected by the toal heavy metals. Application of RSC allows CM to produce mature, safe organic fertilizer after 32 d and reduces the risk of rebound from ARGs, but the issues of sul1 and ermC gene removal cannot be ignored.

Wheat straw pyrochar more efficiently decreased enantioselective uptake of dinotefuran by lettuce and dissemination of antibiotic resistance genes than hydrochar in an agricultural soil

Remediation of soils pollution caused by dinotefuran, a chiral pesticide, is indispensable for ensuring human food security. In comparison with pyrochar, the effect of hydrochar on enantioselective fate of dinotefuran, and antibiotic resistance genes (ARGs) profiles in the contaminated soils remain poorly understood. Therefore, wheat straw hydrochar (SHC) and pyrochar (SPC) were prepared at 220 and 500 °C, respectively, to investigate their effects and underlying mechanisms on enantioselective fate of dinotefuran enantiomers and metabolites, and soil ARG abundance in soil-plant ecosystems using a 30-day pot experiment planted with lettuce. SPC showed a greater reduction effect on the accumulation of R- and S-dinotefuran and metabolites in lettuce shoots than SHC. This was mainly resulted from the lowered soil bioavailability of R- and S-dinotefuran due to adsorption/immobilization by chars, together with the char-enhanced pesticide-degrading bacteria resulted from increased soil pH and organic matter content. Both SPC and SHC efficiently reduced ARG levels in soils, owing to lowered abundance of ARG-carrying bacteria and declined horizontal gene transfer induced by decreased dinotefuran bioavailability. The above results provide new insights for optimizing char-based sustainable technologies to mitigate pollution of dinotefuran and spread of ARGs in agroecosystems.

Emerging soil contamination of antibiotics resistance bacteria (ARB) carrying genes (ARGs): New challenges for soil remediation and conservation

Soil plays a vital role as a nutrient source for microflora and plants in ecosystems. The accumulation and proliferation of antibiotics resistance bacteria (ARB) and antibiotics resistance genes (ARGs) causes emerging soil contamination and pollution, posing new challenges for soil remediation, recovery, and conservation. Fertilizer application in agriculture is one of the most important sources of ARB and ARGs contamination in soils. The recent existing techniques for the remediation of soil polluted with ARB and ARGs are very limited in terms of ARB and ARGs removal in soil. Bioelectrochemical remediation using bioelectrochemical systems such as microbial fuel cells and microbial electrolysis cells are promising technologies for the removal of ARB and ARGs in soil. Herein, diverse sources of ARB and ARGs in soil have been reviewed, their effects on soil microbial diversity have been analyzed, and the causes of ARB and ARGs rapid proliferation in soil are explained. Bioelectrochemical systems used for the remediation of soil contaminated with ARB and ARGs is still in its infancy stage and presents serious disadvantage and limits, therefore it needs to be well understood and implemented. In general, merging soil contamination of ARB and ARGs is an increasing concern threatening the soil ecosystem while the remediation technologies are still challenging. Efforts need to be made to develop new, effective, and efficient technologies for soil remediation and conservation to tackle the spread of ARB and ARGs and overcome the new challenges posed by ARB and ARGs contamination in soil.

Environmental drivers and interaction mechanisms of heavy metal and antibiotic resistome exposed to amoxicillin during aerobic composting

The environmental accumulation and spread of antibiotic resistance pose a major threat to global health. Aerobic composting has become an important hotspot of combined pollution [e.g., antibiotic resistance genes (ARGs) and heavy metals (HMs)] in the process of centralized treatment and resource utilization of manure. However, the interaction mechanisms and environmental drivers of HMs resistome (MRGs), antibiotic resistance (genotype and phenotype), and microbiome during aerobic composting under the widely used amoxicillin (AMX) selection pressure are still poorly understood. Here, we investigated the dynamics of HMs bioavailability and their MRGs, AMX-resistant bacteria (ARB) and antibiotic resistome (ARGs and intI1), and bacterial community to decipher the impact mechanism of AMX by conducting aerobic composting experiments. We detected higher exchangeable HMs and MRGs in the AMX group than the control group, especially for the czrC gene, indicating that AMX exposure may inhibit HMs passivation and promote some MRGs. The presence of AMX significantly altered bacterial community composition and AMX-resistant and -sensitive bacterial structures, elevating antibiotic resistome and its potential transmission risks, in which the proportions of ARB and intI1 were greatly increased to 148- and 11.6-fold compared to the control group. Proteobacteria and Actinobacteria were significant biomarkers of AMX exposure and may be critical in promoting bacterial resistance development. S0134_terrestrial_group was significantly negatively correlated with bla_TEM and czrC genes, which might play a role in the elimination of some ARGs and MRGs. Except for the basic physicochemical (MC, C/N, and pH) and nutritional indicators (NO₃ ^--N, NH₄ ⁺-N), Bio-Cu may be an important environmental driver regulating bacterial resistance during composting. These findings suggested the importance of the interaction mechanism of combined pollution and its synergistic treatment during aerobic composting need to be emphasized.

Thermophilic-mesophilic biodegradation: An optimized dual-stage biodegradation technique for expeditious stabilization of sewage sludge

The present study investigated the stabilization of fresh sewage sludge through a dual-stage biodegradation process; rotary drum composting in series with vermicomposting. After thermophilic exposure in a rotary drum composter, the partially degraded feedstock was separated into S1 without vermiculture, S2 and S3 with Eudrilus eugeniae and Eisenia fetida vermi-monocultures, respectively. The S3-derived vermicompost exhibited an 80% and 88% reduction in CO₂ and ammonium-nitrogen evolution rates, respectively, demonstrating the expedient stabilization of sludge. The robust, more than 85% seed germination index supported S2 and S3 derived vermicompost viability. A significant decrease in heavy metals was evinced with S2 and S3-derived vermicompost; the S1-derived end product exhibited higher Zn, Cr, and Pb levels in the absence of vermicomposting. Furthermore, soil amended with 20% vermicompost from S3 displayed 50% more plant growth than S1. Thus, the optimized thermophilic-mesophilic dual-biodegradation technique stabilizes sewage sludge quickly, has a lot of potential in sludge management facilities around the world, and produces a marketable end product.

Succession and change of potential pathogens in the co-composting of rural sewage sludge and food waste

Composting is an effective way to prevent and control the spread of pathogenic microorganisms which could put potential risk to humans and environment, from rural solid waste, especially sewage sludge and food waste. In the study, we aim to analyze the changes of pathogenic bacteria during the co-composting of rural sewage sludge and food waste. The results showed that only 27 pathogenic bacteria were detected after composting, compared to 50 pathogenic bacteria in the raw mixed pile. About 74% of pathogen concentrations dropped below 1000 copies/g after composting. Lactobacillus, Bacillus, Paenibacillus and Comamonas were the core pathogenic bacteria in the compost, of which concentrations were all significantly lower than that in the raw mixed pile at the end of composting. The concentration of Lactobacillus decreased to 3.03 × 10³ copies/g compared to 0 d with 1.25 × 10⁹ copies/g by the end of the composting, while that of Bacillus, Paenibacillus and Comamonas decreased to 2.77 × 10⁴ copies/g, 2.13 × 10⁴ copies/g and 3.38 × 10² copies/g, respectively, with 1.26 × 10⁷ copies/g, 4.71 × 10⁶ copies/g, 1.69 × 10⁸ copies/g on 0 d. Redundancy analysis (RDA) indicated that physicochemical factors and substances could affect the changes of pathogenic bacteria during composting, while temperature was the key influencing factor. In addition, certain potential pathogenic bacteria, such as Bacteroides-Bifidobacterium, show statistically strong and significant co-occurrence during composting, which may increase the risk of multiple infections and also influence their distribution. These findings provide a theoretical reference for biosafety prevention and control in the treatment and disposal of rural solid waste.

Quality assessment, safety evaluation, and microbiome analysis of night-soil compost from Lahaul valley of northwestern Himalaya

The Himalayan dry toilet system prevalent in the northwestern Himalaya is a traditional practice of converting human faeces into a compost-like soil amendment. The current study evaluated night-soil compost (NSC) for agricultural use by assessing the compost quality, safety, and microbiome properties. Based on the fertility and clean indices determined by the fertility and heavy metal parameters, NSC was categorized as good quality compost with high fertilizing potential and moderate concentration of heavy metals. With respect to pathogens, the faecal coliform levels in the NSC were categorized as safe according to the U.S. Environmental Protection Agency standards. The bacterial community structure based on 16S rRNA gene amplicons revealed a diverse taxonomy with 14 phyla and 54 genera in NSC. Compared to publicly available 16S rRNA gene amplicon data, NSC exhibited predominant phyla (Proteobacteria, Bacteriodetes, Actinobacteria, and Firmicutes) similar to human faeces, cattle manure, food waste compost, vermicompost, and activated sludge. However, statistically, NSC was distinct at the genus level from all other groups. Additionally, pathogenic bacteria with antimicrobial resistance (AMR) genes in the NSC metagenome were determined by performing a standalone BLASTN against the PATRIC database. The analysis revealed 139 pathogenic strains with most pathogens susceptible to antibiotics, indicating lower AMR in the predicted strains. The phytotoxicity of NSC with Pisum sativum var. AS-10 seeds showed a germination index of > 85%, indicating NSC's non-harmful effects on seed germination and root growth. Overall, NSC from Himalayan dry toilets can be used as a soil amendment for food and non-food plants.

Assessment Impacts of Ozone on Salmonella Typhimurium and Escherichia coli O157:H7 in Liquid Dairy Waste

Liquid dairy manure, which is produced in enormous quantities in flush dairy manure management systems, is commonly used as an alternative to chemical fertilizers. It provides nutrient benefits to crops and soils. While dairy waste is a well-accepted and widely used fertilizer, the presence of indicator organisms and human pathogens in manure may lead to pathogen contamination in crops and soils. This study is focused on the examination of ozone gas-based sterilization. In the past, ozone (O3) has been used for sanitizing various foods and solid surfaces, but the potential of O3 for eliminating human pathogens in liquid dairy waste is not studied yet. Pathogens such as Salmonella Typhimurium and Escherichia coli O157:H7 are reported to be present in liquid dairy manure, and this research evaluated the effects of various levels of ozone on the survival of these two pathogens. We designed a continuous type O3 treatment system that has four major components: (1) ozone generator using oxygen; (2) ozone concentration control by mixing with pure air; (3) continuous monitoring of ozone concentrations; and (4) ozone experiment chambers. Various levels of ozone (43.26, 87.40, and 132.46 mg·L−1) were produced in the ozone system, and subsequently, ozone was diffused through liquid manure. Liquid manure was exposed to ozone for multiple durations (30, 60, and 120 min). To determine the effectiveness of O3 in eliminating pathogens, time-series samples were collected and analyzed for determining the levels of S. typhimurium and E. coli O157:H7. Preliminary results showed that ozone concentrations of 132.46 mg/L, and exposure time of 120 min resulted in the reduced levels of E. coli and Salmonella. Low levels of ozone and limited exposure time were found to be less effective in pathogen removal potentially due to high solid contents. Additional studies carrying out experiments to evaluate the impacts of solids in combination with ozone concentrations will provide further insights into developing full-scale ozone-based treatment systems.

Feasibility of sewage sludge and food waste aerobic co-composting: Physicochemical properties, microbial community structures, and contradiction between microbial metabolic activity and safety risks

Co-composting of sludge and food waste eliminates the disadvantages of composting these waste products separately. Specifically, co-composing neutralizes the pollutants and improves the organic matter that occur in sewage sludge, and solves the problem of the low pH values and high moisture content of food waste. However, little is known about the functional microorganisms, microbial metabolic capacity, and biosecurity risks involved in sewage sludge and food waste co-composting. Therefore, this study established four lab-scale composting reactors [T1 (separate composting of food waste), T2 (separate composting of sewage sludge), T3 (sewage sludge and food waste co-composting at a C/N ratio of 25), and T4 (equal proportions composting of sewage sludge and food waste)] to assess the feasibility of sewage sludge and food waste aerobic co-composting. Our findings indicated that polysaccharides and proteins in T3 could be effectively degraded, and the total nutrient levels in T3 were higher than those in the other groups. After composting, the microbial diversity and richness of T3 were higher than that of T1. In later composting stages, the functional microorganisms in T1 maintained higher metabolic activity, however, it also had a higher biosecurity risk than T3 due to the presence of pathogenic bacteria such as Enterococcus_faecalis and Bacillus_circulan. Although the product of T3 could not be used as a microbial fertilizer, its biosecurity risk was lower than that of T1 and could therefore be used as an organic fertilizer. Redundancy analysis (RDA) results indicated that changing the microbial community structure by adjusting key environmental factors could improve composting quality and reduce microbial safety risks. Collectively, our results provide a theoretical basis for the development of co-composting strategies for the biodegradation of perishable solid organic waste, in addition to proposing the risk of pathogenic bacteria exposure that could endanger human and animal health.

Fate of Clostridia and other spore-forming Firmicute bacteria during feedstock anaerobic digestion and aerobic composting

Pathogenic spore-forming Firmicutes are commonly present in animal and human wastes that are used as fertilizers in crop production. Pre-treatments of organic waste prior to land application offer the potential to abate enteric microorganisms, and therefore reduce the risk of contamination of crops or adjacent water resources with pathogens carried in these materials. The inactivation and reduction of gram-positive spore formers such as Clostridium spp., Clostridioides spp. and Bacillus spp. from animal and human waste can be challenging given the recalcitrance of the spores these bacteria produce. Given the significance of these organisms to human and animal health, information concerning spore-forming bacteria inactivation during anaerobic digestion (AD) and aerobic composting (AC) is required as the basis for recommending safe organic waste management practices. In this review, an assessment of the inactivation of spore-forming Firmicutes during AD and AC was conducted to provide guidance for practical management of organic matrices of animal or human origin. Temperature and pH may be the main factors contributing to the inactivation of spore-forming Firmicutes during batch lab-scale AD (log reduction <0.5-5 log). In continuous digesters, wet AD systems do not effectively inactivate spore-forming Firmicutes even under thermopholic conditions (log reduction -1.09 - 0.98), but dry AD systems could be a feasible management practice to inactivate spore-forming Firmicutes from organic materials with high solid content (log reduction 1.77-3.1). In contrast, composting is an effective treatment to abate spore-forming Firmicutes (log reduction 1.7-6.5) when thermophilic conditions last at least six consecutive days. Temperature, moisture content and composting scale are the key operating conditions influencing the inactivation of spore-forming Firmicutes during composting. Where possible, undertaking AD with subsequent composting to ensure the biosafety of digestate before its downstream processing and recycling is recommended to abate recalcitrant bacteria in digestate.

Effect of biochar addition on the dynamics of antibiotic resistant bacteria during the pig manure composting

In present study, the taxonomic variation of antibiotic resistant bacteria (ARB) in pig manure (PM) composting with coconut shell biochar (CSB) and bamboo biochar (BB) addition was investigated. The experiment was divided into three treatments: T1 (as control or without biochar amendment), T2 was added 10% coconut shell biochar and T3 supplemented with 10% bamboo biochar. The initial feed stock were properly homogenized using a mechanical crusher. PM and wheat straw (WS) were mixed in a 5: 1 dry weight ratio to adjust the initial carbon/nitrogen ratio 25:1, bulk density to ~0.5 (kg/L) and ~60% moisture content, respectively. This experiment was lasted for 42 days. The results indicated the bacterial communities in the three treatments were more different in terms of relative abundance and diversity of dominant bacteria. The control group had the highest abundance of Kingdome bacteria. The changes in ARB was noticed by variation in the relative abundances of Actinobacteria, Proteobacteria, Firmicutes and Bacteroidota. At the end of composting (on day 42), the total RAs of ARB at the class, order, and family levels were considerably reduced in T2 and T3 by ~35.78-38.75%, 36.42-40.63% and 45.82-47.70%, respectively. But in T1 was decreased by 6.16-8.62%, 7.93-8.72% and 8.70-10.15%, as compared with the day 0 sample. However, the CSB was much more effective to reduce 55 to 60% of ARB than T3 or BB applied treatment has 40 to 42% ARB reduction, while control has certainly very less RAa of ARB reduction. Finally, the biochar amendment was significant approach to mitigate the total ARB abundance in compost and it's further used for organic farming purposes.

Non-Thermal Atmospheric Plasma for Microbial Decontamination and Removal of Hazardous Chemicals: An Overview in the Circular Economy Context with Data for Test Applications of Microwave Plasma Torch

The transformation of our linear “take-make-waste” system to a cyclic flow of materials and energy is a priority task for society, but the circular use of waste streams from one industry/sector as a material input for another must be completely safe. The need for new advanced technologies and methods ensuring both microbiological safety and the removal of potential chemical residues in used materials and products is urgent. Non-thermal atmospheric plasma (cold atmospheric plasma—CAP) has recently attracted great research interest as an alternative for operative solutions of problems related to safety and quality control. CAP is a powerful tool for the inactivation of different hazardous microorganisms and viruses, and the effective decontamination of surfaces and liquids has been demonstrated. Additionally, the plasma’s active components are strong oxidizers and their synergetic effect can lead to the degradation of toxic chemical compounds such as phenols and azo-dyes.

Intraspecific and interspecific quorum sensing of bacterial community affects the fate of antibiotic resistance genes during chicken manure composting under penicillin G stress

In this study, the effects of penicillin G (PENG) on the fate of bacterial communities and β-lactamase antibiotic resistance genes (ARGs) during chicken manure composting were assessed, to illustrate the roles of PENG in ARGs behavior. The results showed that the total absolute abundances of 9 ARGs and 4 mobile genetic elements (MGEs) was significantly increased by PENG (P < 0.05). Dozens of potential hosts for ARGs were predominantly affiliated with Firmicutes, Proteobacteria, and Actinobacteria. Meanwhile, the higher concentration of PENG significantly increased the abundance of luxI and luxS in quorum sensing (QS) (P < 0.05), which enhanced the frequency of inter/intraspecific gene "communication." Redundancy analysis and structural equation modeling further revealed that QS had a strong regulatory role in horizontal gene transfer of ARGs mediated via MGEs. These results provide new insight into the mechanism of ARGs propagation in aerobic composting modified by PENG.

Environmental impacts of hazardous waste, and management strategies to reconcile circular economy and eco-sustainability

The rise in living standards and the continuous development in the global economy led to the depletion of resources and increased waste generation per capita. This waste might posture a significant threat to human health or the environmental matrices (water, air, soil) when inadequately treated, transported, stored, or managed/disposed of. Therefore, effective waste management in an economically viable and environmentally friendly way has become meaningful. Prominent technology is the need of the day for circular economy and sustainable development to reduce the speed of depletion in resources and produce an alternative means for the future demands in the different sectors of science and technology. In order to meet the potential requirements for energy production or producing secondary raw material, solid waste may be the prime source. The activities of living organisms convert waste products in one form or another in which electronic waste (e-waste) is a modern-day problem that is growing by leaps and bounds. The disposal protocols of the e-waste management need to be given proper attention to avoid its hazardous impacts. The e-waste is obtained from any equipment or devices that run by electricity or batteries like laptops, palmtops, computers, televisions, mobile phones, digital video discs (DVD), and many more. E-waste is one of the rapidly growing causes of world pollution today. Plenty of research is available in the scientific literature, which shows different approaches being set up and followed to manage and dispose of waste products. These strategies to manage waste products designed by the states all over the globe revolves around minimal production, authentic techniques for the management of waste produced, reuse and recycling, etc. The virtual survey of the available literature on waste management shows that it lacks specificity regarding the management of waste products parallel to ecological sustainability. The presented review covers the sources, potential environmental impacts, and highlights the importance of waste management strategies to provide the latest and updated knowledge. The review also put forward the countermeasures that need to be taken on national and International levels addressing the sensitive issue of waste management.

Industrial Composting of Sewage Sludge: Study of the Bacteriome, Sanitation, and Antibiotic-Resistant Strains

Wastewater treatment generates a huge amount of sewage sludge, which is a source of environmental pollution. Among the alternatives for the management of this waste, industrial composting stands out as one of the most relevant. The objective of this study was to analyze the bacterial population linked to this process and to determine its effectiveness for the reduction, and even elimination, of microorganisms and pathogens present in these organic wastes. For this purpose, the bacteriome and the fecal bacteria contamination of samples from different sewage sludge industrial composting facilities were evaluated. In addition, fecal bacteria indicators and pathogens, such as Salmonella, were isolated from samples collected at key stages of the process and characterized for antibiotic resistance to macrolide, β-lactam, quinolone, and aminoglycoside families. 16S rRNA phylogeny data revealed that the process clearly evolved toward a prevalence of Firmicutes and Actinobacteria phyla, removing the fecal load. Moreover, antibiotic-resistant microorganisms present in the raw materials were reduced, since these were isolated only in the bio-oxidative phase. Therefore, industrial composting of sewage sludge results in a bio-safe final product suitable for use in a variety of applications.

Effect of a low-cost and highly efficient passivator synthesized by alkali-fused fly ash and swine manure on the leachability of heavy metals in a multi-metal contaminated soil

Soil pollution, caused by heavy metals, is an environmental problem that requires an urgent solution in China. Chemical passivation is a technology that uses various passivators to reduce the availability of heavy metals in soil and realize the remediation of contaminated soil. In this study, we examined the effects of fly ash (FA), alkali-fused fly ash (AFFA), swine manure biochar (SB), and modifying biochar (MB) on the leachability of Cu, Zn, Pb, and Cd via soil culture experiments. The results showed that the addition of AFFA, SB, and MB significantly reduced the extractable contents of Cu, Pb, and Cd in the soil. AFFA and MB had the best passivation effect, followed by SB and FA. The passivation effect on Pb was the best, followed by that on Cu and Cd. AFFA modification significantly improved the passivation effect of MB on Cu, Pb, and Cd in composite contaminated soil. With the addition of 3% MB, the Pb, Cu, and Cd extracted by TCLP decreased by 95.7, 74.1, and 59.1%, respectively. Correlation analysis, Fourier transform infrared spectrometry, scanning electron microscopy, and energy-dispersive X-ray spectroscopy showed that the passivation mechanism is mainly due to an increase in the soil pH, silicate content, and cohesiveness. The soil culture experiments in this study proved that MB is a low-cost and highly efficient organic-inorganic composite passivator for multi-metal contaminated soils.

Occurrence of heavy metals, antibiotics, and antibiotic resistance genes in different kinds of land-applied manure in China

Various pollutants remaining in the livestock and poultry manures pose potential threat to the soil ecosystem during land application, whose impact should be appreciated. The occurrence of heavy metals, antibiotics, and antibiotic resistance genes (ARGs) in swine manure (SM), chicken manure (CM), and the SM organic fertilizer (OF) were investigated. The order of total concentrations of antibiotics detected in manures was as follows: SM > CM > OF. The amount of ciprofloxacin (CIP) in SM reached up to 6.61 mg/kg, which only occupied 1% of the antibiotic concentration reported in the past years. The total concentration of thirteen ARGs in CM ranked first, reaching 7.35 × 10¹¹ copies/g, among which the strB gene was detected with the highest concentration. It was worth noting that the qnr ARGs were persistent in OF with the absence of corresponding antibiotics, indicating ARGs were harder to remove than antibiotics during manure composting. Zn and Cu (46.5-843 mg/kg) were obviously higher than other seven heavy metals, and significantly correlated with most ARGs (p < 0.01). This study provided the basic data of the pollution in animal manures that will be land-applied, illuminating the original source of potential risk in soil ecosystem.

Visible-light activation of peroxymonosulfate by NiCo2O4/Bi24O31Br10 to accelerate tetracycline degradation

Possible degradation mechanism with NiCo₂O₄/Bi₂₄O₃₁Br₁₀ in a PMS/vis system.