Microbiome multi-omics can accelerate human excrement composting research.

In this editorial, we discuss the need for a new, long-term strategy for managing human excrement (feces and urine) to facilitate health equity and promote environmental sustainability. Human excrement composting (HEC), a human-directed process driven by highly variable and diverse microbiomes, provides a means to advance this need and we discuss how microbiome science can help to advance HEC research. We argue that the technological advancements that have driven the growth of microbiome science, including microbiome and untargeted metabolome profiling, can be leveraged to enhance our understanding of safe and efficient HEC. We conclude by presenting our perspective on how we can begin applying these technologies to develop accessible procedures for safe HEC. Video Abstract.

Urine-derived stem cells serve as a robust platform for generating native or engineered extracellular vesicles.

BACKGROUND: Mesenchymal stromal cell (MSC) therapy holds great potential yet efficacy and safety concerns with cell therapy persist. The beneficial effects of MSCs are often attributed to their secretome that includes extracellular vesicles (EVs). EVs carry biologically active molecules, protected by a lipid bilayer. However, several barriers hinder large-scale MSC EV production. A serum-free culturing approach is preferred for producing clinical-grade MSC-derived EVs but this can affect both yield and purity. Consequently, new strategies have been explored, including genetically engineering MSCs to alter EV compositions to enhance potency, increase circulation time or mediate targeting. However, efficient transfection of MSCs is challenging. Typical sources of MSC include adipose tissue and bone marrow, which both require invasive extraction procedures. Here, we investigate the use of urine-derived stem cells (USCs) as a non-invasive and inexhaustible source of MSCs for EV production. METHODS: We isolated, expanded, and characterized urine-derived stem cells (USCs) harvested from eight healthy donors at three different time points during the day. We evaluated the number of clones per urination, proliferation capacity and conducted flow cytometry to establish expression of surface markers. EVs were produced in chemically defined media and characterized. PEI/DNA transfection was used to genetically engineer USCs using transposon technology. RESULTS: There were no differences between time points for clone number, doubling time or viability. USCs showed immunophenotypic characteristics of MSCs, such as expression of CD73, CD90 and CD105, with no difference at the assessed time points, however, male donors had reduced CD73 + cells. Expanded USCs were incubated without growth factors or serum for 72 h without a loss in viability and EVs were isolated. USCs were transfected with high efficiency and after 10 days of selection, pure engineered cell cultures were established. CONCLUSIONS: Isolation and expansion of MSCs from urine is non-invasive, robust, and without apparent sex-related differences. The sampling time point did not affect any measured markers or USC isolation potential. USCs offer an attractive production platform for EVs, both native and engineered.

The Importance of Urine Sediment Analysis.

BACKGROUND: Urinary sediment is an important part of routine urine test, which plays an irreplaceable role in the diagnosis of diseases, monitoring of treatment effect, and prognosis judgment [1]. METHODS: Through the results of urine dry chemistry and microscopic examination of urinary sediment, we inter-preted and analyzed the clinical significance of urinary casts in urinary sediment. RESULTS: In patients with new urinary system diseases abnormal urine results appear earlier than changes in serum renal function indicators, especially when the urine sediment shows typical casts, which can provide an important basis for clinical diagnosis. CONCLUSIONS: Clinical laboratory personnel should attach great importance to the morphological examination of urinary sediment and master the diagnostic significance of the formed components of urinary sediment for various diseases, so as to better assist clinical disease diagnosis.

Carbapenem-resistant Acinetobacter baumannii (CRAB): metabolic adaptation and transcriptional response to human urine (HU).

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a major human pathogen and a research priority for developing new antimicrobial agents. CRAB is a causative agent of a variety of infections in different body sites. One of the manifestations is catheter-associated urinary tract infection, which exposes the bacteria to the host's urine, creating a particular environment. Exposure of two CRAB clinical isolates, AB5075 and AMA40, to human urine (HU) resulted in the differential expression levels of 264 and 455 genes, respectively, of which 112 were common to both strains. Genes within this group play roles in metabolic pathways such as phenylacetic acid (PAA) catabolism, the Hut system, the tricarboxylic acid (TCA) cycle, and other processes like quorum sensing and biofilm formation. These results indicate that the presence of HU induces numerous adaptive changes in gene expression of the infecting bacteria. These changes presumably help bacteria establish and thrive in the hostile conditions in the urinary tract. These analyses advance our understanding of CRAB's metabolic adaptations to human fluids, as well as expand knowledge on bacterial responses to distinct human fluids containing different concentrations of human serum albumin (HSA).

Transposon mutagenesis screen in Klebsiella pneumoniae identifies genetic determinants required for growth in human urine and serum.

Klebsiella pneumoniae is a global public health concern due to the rising myriad of hypervirulent and multidrug-resistant clones both alarmingly associated with high mortality. The molecular mechanisms underpinning these recalcitrant K. pneumoniae infection, and how virulence is coupled with the emergence of lineages resistant to nearly all present-day clinically important antimicrobials, are unclear. In this study, we performed a genome-wide screen in K. pneumoniae ECL8, a member of the endemic K2-ST375 pathotype most often reported in Asia, to define genes essential for growth in a nutrient-rich laboratory medium (Luria-Bertani [LB] medium), human urine, and serum. Through transposon directed insertion-site sequencing (TraDIS), a total of 427 genes were identified as essential for growth on LB agar, whereas transposon insertions in 11 and 144 genes decreased fitness for growth in either urine or serum, respectively. These studies not only provide further knowledge on the genetics of this pathogen but also provide a strong impetus for discovering new antimicrobial targets to improve current therapeutic options for K. pneumoniae infections.

Advanced electrochemical membrane technologies for near-complete resource recovery and zero-discharge of urine: Performance optimization and evaluation.

The depletion of nutrient sources in fertilizers demands a paradigm shift in the treatment of nutrient-rich wastewater, such as urine, to enable efficient resource recovery and high-value conversion. This study presented an integrated bipolar membrane electrodialysis (BMED) and hollow fiber membrane (HFM) system for near-complete resource recovery and zero-discharge from urine treatment. Computational simulations and experimental validations demonstrated that a higher voltage (20 V) significantly enhanced energy utilization, while an optimal flow rate of 0.4 L/min effectively mitigated the negative effects of concentration polarization and electro-osmosis on system performance. Within 40 min, the process separated 90.13% of the salts in urine, with an energy consumption of only 8.45 kWh/kgbase. Utilizing a multi-chamber structure for selective separation, the system achieved recovery efficiencies of 89% for nitrogen, 96% for phosphorus, and 95% for potassium from fresh urine, converting them into high-value products such as 85 mM acid, 69.5 mM base, and liquid fertilizer. According to techno-economic analysis, the cost of treating urine using this system at the lab-scale was $6.29/kg of products (including acid, base, and (NH4)2SO4), which was significantly lower than the $20.44/kg cost for the precipitation method to produce struvite. Excluding fixed costs, a net profit of $18.24/m3 was achieved through the recovery of valuable products from urine using this system. The pilot-scale assessment showed that the net benefit amounts to $19.90/m3 of urine, demonstrating significant economic feasibility. This study presents an effective approach for the near-complete resource recovery and zero-discharge treatment of urine, offering a practical solution for sustainable nutrient recycling and wastewater management.

Nitrosamine formation driven by electrochemical chlorination of urine-containing source waters: Effects of operational conditions.

We investigated the formation of nitrosamines from urine during electrochemical chlorination (EC) using dimensionally stable anodes. Short-term electrolysis (< 1 h) of urine at 25 mA cm-2 generated seven nitrosamines (0.1-7.4 µg L-1), where N-nitrosodimethylamine, N-nitrosomethylethylamine, and N-nitrosodiethylamine were predominant with concentrations ranging from 1.2 to 7.4 µg L-1. Mechanistic studies showed that the formation kinetics of nitrosamines was influenced by urine aging and composition, with fresh urine generating the highest levels (0.9-5.8 µg L-1) compared with aged, centrifuged, or filtered urine (0.2-4.1 µg L-1). Concurrently, studies on urine pretreatment through filtration and centrifugation underscored the significance of nitrogenous metabolites (such as protein-like products and urinary amino acids) and particle-associated humic fractions in nitrosamine formation during EC of urine. This finding was confirmed through chromatographic and spectroscopic studies utilizing LCOCD, Raman spectra, and 3DEEM fluorescence spectra. Parametric studies demonstrated that the ultimate [nitrosamines] increased at a pH range of 4.5-6.2, and with increasing [bromide], [ammonium], and current density. Conversely, sulfate and carbonate ions inhibited nitrosamine formation. Moreover, the implications of EC in urine-containing source waters were evaluated. The results indicate that regardless of the urine source (individual volunteers, septic tank, swimming pool, untreated municipal wastewater), high levels of nitrosamines (0.1-17.6 µg L-1) were generated, surpassing the potable reuse guideline of 10 ng L-1. Overall, this study provides insights to elucidate the mechanisms underlying nitrosamine formation and optimize the operating conditions. Such insights facilitate suppressing the generation of nitrosamine byproducts during electrochemical treatment of urine-containing wastewater.

Potassium and ammonium recovery in treated urine by zeolite based mixed matrix membranes.

Nitrogen, phosphorus and potassium are essential for crop growth, which are abundant in urine. Although numerous studies have developed techniques to recover ammonium and phosphorus from urine, limited research made efforts on the recovery of potassium, which is a non-renewable resource with uneven global distribution. In this study, we explored the possibility of zeolite based mixed matrix membranes (MMMs) to selectively recover ammonium and potassium from urine, with minimal detention of sodium. The findings demonstrated that upon the pre-treatment of zeolites with sodium chloride solution, a 70 wt% zeolite loaded MMM could achieve 69.3 % recovery of potassium and almost full recovery of ammonium. By varying the desorption temperatures and MMMs production process, it was discovered that stepwise backwash at low temperature (276 K) greatly lowered sodium recovery whilst simultaneously enhancing the recovery of potassium and ammonium. This study demonstrates the potential of recovering potassium and ammonium from urine using zeolite-loaded MMMs, coupled with achieving low-sodium recovery.

Improving contaminant removal and inhibiting CH4 and H2S emissions from septic tanks: Nitrified human urine as a source of electron acceptor.

Septic tanks are widely adopted in decentralized household wastewater treatment systems serving billions of people globally. Due to the lack of effective electron acceptors, insufficient nutrient removal and the emission of harmful gases, e. g. H2S, CH4, etc., are the common drawbacks. In the present work, we attempted to supplement nitrite into septic tanks as an electron acceptor, via nitrifying human urine source-separated from blackwater, to overcome these drawbacks. Partial or complete nitritation of source-separated urine was achieved in a sequencing batch reactor. The addition of nitrified urine into septic tanks improved organic and nitrogen removals in blackwater up to 90 % and 70 %, respectively. The emission of harmful gases from the septic tanks was stably diminished, with more than 75 % of CH4, CO2 and H2S reductions. Nitrite addition significantly reduced the abundance of hydrogenotrophic methanogens in septic tanks. Though the activity of sulfate-reducing bacteria recovered after the initial inhibition upon nitrite addition, the bio-generated H2S was retained in water since the increased wastewater pH after nitrite addition promoted the disassociation of H2S in aqueous solution.

Exploring the therapeutic potential of urine-derived stem cell exosomes in temporomandibular joint osteoarthritis.

Temporomandibular joint osteoarthritis (TMJOA) is a degenerative ailment that causes slow cartilage degeneration, aberrant bone remodeling, and persistent discomfort, leading to a considerable reduction in the patient's life quality. Current treatment options for TMJOA have limited efficacy. This investigation aimed to explore a potential strategy for halting or reversing the progression of TMJOA through the utilization of exosomes (EXOs) derived from urine-derived stem cells (USCs). The USC-EXOs were obtained through microfiltration and ultrafiltration techniques, followed by their characterization using particle size analysis, electron microscopy, and immunoblotting. Subsequently, an in vivo model of TMJOA induced by mechanical force was established. To assess the changes in the cartilage of TMJOA treated with USC-EXOs, we performed histology analysis using hematoxylin-eosin staining, immunohistochemistry, and histological scoring. Our findings indicate that the utilization of USC-EXOs yields substantial reductions in TMJOA, while concurrently enhancing the structural integrity and smoothness of the compromised condylar cartilage surface. Additionally, USC-EXOs exhibit inhibitory effects on osteoclastogenic activity within the subchondral bone layer of the condylar cartilage, as well as attenuated apoptosis in the rat TMJ in response to mechanical injury. In conclusion, USC-EXOs hold considerable promise as a potential therapeutic intervention for TMJOA.

Urinary Tract Cytopathology: Current and Future Impact on Patient Care.

Urine cytology is a non-invasive, cost-efficient, and sensitive test to detect high-grade urothelial carcinoma. The Paris System (TPS) for Reporting Urinary Cytology is an evidence-based system that uses the risk of malignancy to guide patient management. Since its inception, TPS has standardized urine cytology reports, facilitating communication among pathologists and between pathologists and clinicians. It is imperative to correlate the urine cytology findings with the concurrent tissue sample to avoid false-negative and false-positive results when possible. Several ancillary tests and artificial intelligence algorithms are being developed to increase the accuracy of urine cytology interpretation.

Circular fertilisers combining dehydrated human urine and organic wastes can fulfil the macronutrient demand of 15 major crops.

This study evaluated the potential for combining dehydrated human urine with one other form of organic waste to create circular fertilisers tailored to meet the macronutrient demand of 15 major crops cultivated globally. Through a reverse blending modelling approach, data on 359 different organic wastes were used to identify 38 fertiliser blends. Materials found to be particularly suitable as blending materials were various biochars and ashes, due to their low nitrogen and high phosphorus and/or potassium content, and byproduct concentrates, due to their high phosphorus content, since the nitrogen content of human urine is disproportionately higher than its phosphorus content. Several organic wastes were suitable for fertilising more than one crop. The macronutrient content of the simulated fertiliser blends was comparable to that of blended inorganic fertilisers, but only a few blends precisely matched the macronutrient demand of crops. Fertilising crops with some simulated fertilisers would potentially result in excess application of one or more macronutrients, and thus overfertilisation. For organic wastes with data available on their content of six or more heavy metals, it was found that the simulated fertilisers generally met European Union regulations on use of fertilisers of organic origin in agriculture. Overall, these findings suggest that fertiliser blends combining dehydrated human urine and organic wastes, both of which are widely available globally, could replace inorganic blended fertilisers in agriculture. Such recycling would help the global food system and water sector transition to circularity and promote better management of plant-essential nutrients in society.

Age-related trends in urine specific gravity in apparently healthy cats.

OBJECTIVES: Urine specific gravity (USG) is the most common method for the estimation of urine concentration in cats. Utilization of USG as a screening tool is easily accessible and is of low cost to the client if strategically utilized in settings of higher diagnostic value. There is currently minimal population information regarding how USG changes across ages in cats. METHODS: Data were collected from electronic pet medical records from more than 1000 hospitals and screened for cats with an apparently healthy clinical status and complete diagnostic information. USG was compared with age in multiple analyses to examine the relationship between the variables. RESULTS: In the absence of other indicators of disease, renal concentrating ability begins to diminish, on average, starting at approximately 9 years of age. By age group, cats aged 11-15 years (1.044, 95% confidence interval [CI] 1.043-1.044) had statistically significantly lower mean USGs compared with cats aged less than 1 year (1.049, 95% CI 1.048-1.051; P <0.001), 1-6 years (1.049, 95% CI 1.049-1.050; P <0.001) or 7-10 years (1.049, 95% CI 1.048-1.049; P <0.001). Cats aged ⩾15 years (1.038, 95% CI 1.036-1.040) had statistically significantly lower mean USGs compared with cats aged less than 1 year (P <0.001), 1-6 years (P <0.001), 7-10 years (P <0.001) or 11-15 years (P <0.001). CONCLUSIONS AND RELEVANCE: Renal concentrating ability begins to diminish, on average, starting at approximately 9 years of age and is progressive as cat age increases. This study provides important and new information to help improve screening practices for disorders of concentrating ability in cats.

Clinical sensitivity and time-to-result of a cascaded pooled testing approach for assessing the prevalence and intensity of Schistosoma haematobium infection.

BACKGROUND: This study compared the clinical sensitivity and the time-to-result of an individual testing (IT) and a cascaded pooled testing approach (CPT; a positive test result in a pooled sample triggers examination of smaller-sized pools or individual samples) for assessing the prevalence and the intensity of Schistosoma haematobium infection. We also compared the sensitivity of the CPT in detecting S. haematobium infection when deploying urine filtration microscopy (UFM) vs. urine reagent strips (URS), and testing 10 mL vs. 15 mL of urine. METHODOLOGY/PRINCIPAL FINDINGS: Between October 2021 and April 2022, S. haematobium eggs were counted in urine samples collected from school-aged children living in the Afar and Gambella Regional States of Ethiopia. Urine samples were collected at baseline (n = 1,288), and one month after administration of praziquantel (n = 118). All urine samples were processed through both an IT and a CPT approach (pools of 5, 10, 20, and 40 individual samples), deploying UFM (10 mL) and URS (10 mL). In addition, 15 mL urine was processed through the CPT deploying UFM. At baseline, the prevalence of S. haematobium infection estimated when using UFM and deploying a CPT approach was significantly lower (17.3%) compared to an IT approach (31.5%). The clinical sensitivity of the CPT in detecting S. haematobium eggs was 51.7%. The sensitivity increased significantly as a function of increasing log transformed urine egg counts (UECs) of the individual samples (OR 2.71, 95%CI 1.63 - 4.52). The sensitivity was comparable when the amount of urine examined was 10 mL (51.7%) vs. 15 ml (50.8%), and when UFM was used for testing vs. URS (51.5%). The mean log UECs estimated following the CPT approach was lower compared to the estimate by the IT (p <0.001). UECs of the individual samples estimated using the IT and CPT approaches were moderately correlated (r = 0.59 when 10 mL and 15 mL urine was examined after pooling). CPT reduced the time needed for processing urine samples and testing for S. haematobium infection by 29% with UFM and by 27.7% with URS. CONCLUSIONS/SIGNIFICANCE: CPT based on UFM and URS techniques may help to rapidly identify areas with higher prevalence of S. haematobium infection (hotspots) in a population. However, the performance of this approach in estimating the prevalence of infection may be compromised, particularly in endemic areas with low intensity infection.

Metabolomics study of dietary Pleurotus eryngii ß-type glycosidic polysaccharide on colitis induced by dextran sodium sulfate in mice - Exploration for the potential metabolic indicators in urine and serum.

Pleurotus eryngii, an edible mushroom recognized for its potent polysaccharides, demonstrates significant regulatory effects on metabolic processes. ß-glucan (WPEP) derived from P. eryngii has been noted for its therapeutic potential, exhibiting notable benefits in alleviating colonic inflammation and restructuring gut microbiota in mice treated with dextran sodium sulfate (DSS). This study focuses on utilizing DSS-induced colitis mice to explore the efficacy and underlying mechanisms of WPEP in ameliorating colitis, employing a metabolomics approach analyzing urine and serum. The findings reveal that WPEP administration effectively regulates metabolic imbalances in DSS mice, impacting purine metabolism, pentose and glucuronic acid interconversion, amino acid metabolism, primary bile acid biosynthesis, citric acid cycle, and lipid metabolism. Furthermore, WPEP demonstrates a capacity to modulate colitis by regulating diverse metabolic pathways, consequently influencing intestinal barrier integrity, motility, inflammation, oxidative stress, and immunity. These insights suggest that WPEP is a promising food component for managing inflammatory bowel diseases.

Genomic Profile of a Multidrug-Resistant Klebsiella pneumoniae Strain Isolated from a Urine Specimen.

Klebsiella pneumoniae is an opportunistic pathogen mostly found in health care-associated infections but can also be associated with community-acquired infections and is in critical need of new antimicrobial agents for strains resistant to carbapenems. The prevalence of carbapenemase-encoding genes varies among studies. Multidrug-resistant K. pneumoniae strains can harbor several antimicrobial-resistant determinants and mobile genetic elements (MGEs), along with virulence genetic determinants in community settings. We aim to determine the genetic profile of a multidrug-resistant K. pneumoniae strain isolated from a patient with community-acquired UTI. We isolated a K. pneumoniae strain UABC-Str0120, from a urine sample of community-acquired urinary tract infection. Antimicrobial susceptibility tests and Whole-genome sequencing (WGS) were performed. The phylogenetic relationship was inferred by SNPs calling and filtering. UABC-Str0120 showed resistance toward ß-lactams, combinations with ß-lactamase inhibitors, and carbapenems. WGS revealed the presence of genes conferring resistance to aminoglycosides, ß-lactams, carbapenems, quinolones, sulfonamides, phosphonates, phenicols, and quaternary ammonium compounds, 77 subsystems of virulence genes were identified, and an uncommon sequence type ST5889 was also determined. The sequenced strain harbors several MGEs. The UABC-Str0120 recovered from a urine sample harbors several virulence and antimicrobial resistance determinants, which assembles an endangering combination for an immunocompromised or a seemly healthy host, given its presence in a community setting.

Evaluation of the DxU 850m Iris automated urine microscopy analyzer for identifying culture-negative urine samples: From a perspective of reducing urine culture number.

We evaluated the DxU 850m Iris Urine Microscopy analyzer as a screening tool for excluding negative urine samples (n = 1337). At a cutoff of 103 colony counts·mL-1, sensitivity was 55.1 %, specificity 68.6 %. The DxU 850m Iris does not offer acceptable prediction of culture-negative urine samples at the tested cutoff.

Increasing urine nitrification performance with sequential membrane aerated biofilm reactors.

This study aimed to investigate whether separating organics depletion from nitrification increases the overall performance of urine nitrification. Separate organics depletion was facilitated with membrane aerated biofilm reactors (MABRs). The high pH and ammonia concentration in stored urine inhibited nitrification in the first stage and therewith allowed the separation of organics depletion from nitrification. An organics removal of 70 % was achieved at organic loading rates in the influent of 3.7 gCOD d-1 m-2. Organics depletion in a continuous flow stirred tank reactor (CSTR) for organics depletion led to ammonia stripping through diffused aeration of up to 13 %. Using an MABR, diffusion into the lumen amounted for 4 % ammonia loss only. In the MABR, headspace volume and therefore ammonia loss through the headspace was negligible. By aerating the downstream MABR for nitrification with the off-gas of the MABR for organics depletion, 96 % of the ammonia stripped in the first stage could be recovered in the second stage, so that the overall ammonia loss was negligibly low. Nitrification of the organics-depleted urine was studied in MABRs, CSTRs, and sequencing batch reactors in fed batch mode (FBRs), the latter two operated with suspended biomass. The experiments demonstrated that upstream organics depletion can double the nitrification rate. In a laboratory-scale MABR, nitrification rates were recorded of up to 830 mgNL-1 d-1 (3.1 gN m-2 d-1) with ambient air and over 1500 mgNL-1 d-1 (6.7 gN m-2 d-1) with oxygen-enriched air. Experiments with a laboratory-scale MABR showed that increasing operational parameters such as pH, recirculation flow, scouring frequency, and oxygen content increased the nitrification rate. The nitrification in the MABR was robust even at high pH setpoints of 6.9 and was robust against process failures arising from operational mistakes. The hydraulic retention time (HRT) required for nitrification was only 1 to 2 days. With the preceding organics depletion, the HRT for our system requires 2 to 3 days in total, whereas a combined activated sludge system requires 4 to 8 days. The N2O concentration in the off-gas increases with increasing nitrification rates; however, the N2O emission factor was 2.8 % on average and independent of nitrification rates. These results indicate that the MABR technology has a high potential for efficient and robust production of ammonium nitrate from source-separated urine.

Electrochemical degradation of acetaminophen in urine matrices: Unraveling complexity and implications for realistic treatment strategies.

Urine has an intricate composition with high concentrations of organic compounds like urea, creatinine, and uric acid. Urine poses a formidable challenge for advanced effluent treatment processes following urine diversion strategies. Urine matrix complexity is heightened when dealing with pharmaceutical residues like acetaminophen (ACT) and metabolized pharmaceuticals. This work explores ACT degradation in synthetic, fresh real, and hydrolyzed real urines using electrochemical oxidation with a dimensional stable anode (DSA). Analyzing drug concentration (2.5 - 40 mg L-1) over 180 min at various current densities in fresh synthetic effluent revealed a noteworthy 75% removal at 48 mA cm-2. ACT degradation kinetics and that of the other organic components followed a pseudo-first-order reaction. Uric acid degradation competed with ACT degradation, whereas urea and creatinine possessed higher oxidation resistance. Fresh real urine presented the most challenging scenario for the electrochemical process. Whereas, hydrolyzed real urine achieved higher ACT removal than fresh synthetic urine. Carboxylic acids like acetic, tartaric, maleic, and oxalic were detected as main by-products. Inorganic ionic species nitrate, nitrite, and ammonium ions were released to the medium from N-containing organic compounds. These findings underscore the importance of considering urine composition complexities and provide significant advancements in strategies for efficiently addressing trace pharmaceutical contamination.