Graphene-coated sand for enhanced water reuse: Impact on water quality and chemicals of emerging concern.

This paper investigates the potential of graphene-coated sand (GCS) as an advanced filtration medium for improving water quality and mitigating chemicals of emerging concern (CECs) in treated municipal wastewater, aiming to enhance water reuse. The study utilizes three types of sand (Ottawa, masonry, and concrete) coated with graphene to assess the impact of surface morphology, particle shape, and chemical composition on coating and filtration efficiency. Additionally, sand coated with graphene and activated graphene coated sand were both tested to understand the effect of coating and activation on the filtration process. The materials were characterized using digital microscopy, Raman spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction analysis. The material's efficiency in removing turbidity, nutrients, chemical oxygen demand (COD), bacteria, and specific CECs (Aciclovir, Diatrizoic acid, Levodopa, Miconazole, Carbamazepine, Diphenhydramine, Irbesartan, Lidocaine, Losartan, and Sulfamethoxazole) was studied. Our findings indicate that GCS significantly improves water quality parameters, with notable efficiency in removing turbidity, COD (14.1 % and 69.1 % removal), and bacterial contaminants (64.9 % and 99.9 % removal). The study also highlights the material's capacity to remove challenging CECs like Sulfamethoxazole (up to 80 % removal) and Diphenhydramine (up to 90 % removal), showcasing its potential as a sustainable solution for water reuse applications. This research contributes to the field by providing a comprehensive evaluation of GCS in water treatment, suggesting its potential for removing CECs from treated municipal wastewater.

Training in Vascular Microsurgery: The Ex Vivo Biological Model on Domestic Turkey Leg (Meleagris gallopavo).

There are various models for practicing microsurgical anastomoses, from synthetic to ex vivo and in vivo biological ones. In this study, we present the domestic turkey (Meleagris gallopavo) as an ex vivo biological model in the practice of surgical anastomoses. In our opinion, it represents a model that is very similar to a human one, low cost, and easy to find. In fact, our study shows that the diameters of the arteries and veins used for anastomoses (tibial artery diameter: 2.5 ±â€…0.6 mm; tibial vein diameter: 3.5 ±â€…1.2 mm) are similar to those of human arteries and veins most frequently used in microsurgical free flaps. So, we believe that this animal model is a great model for microsurgical training for doctors who approach this difficult and long to learn discipline.

Synthesis, characterization, and environmental applications of graphene-coated sand: A review.

Global water quality has deteriorated, leaving over 844 million individuals without access to clean drinking water. While sand filters (SF) offer a solution, their limited surface area and adsorption capacity for emerging contaminants remain a challenge. This has prompted the development of new materials such as graphene-coated sand (GCS) to enhance the sand's adsorptive properties. Notably, GCS also possesses inherent anti-bacterial properties and can function as a photocatalyst when exposed to UV and visible light, offering enhanced water purification. This manuscript 1) reviews the synthesis of GCS, detailing the characterization techniques employed to understand its structure, composition, and multifunctional properties and 2) highlights the superior efficacy of GCS in removing contaminants, including metals (>95 % removal of Cd2+, Pb2+, Zn2+, and Cu2+ in low pH environment), sulfides (full removal compared to 26 % removal by raw sand), antibiotics (98 % removal of tetracycline), and bacteria (complete cell membrane destruction), compared to traditional SF. Due to its enhanced performance and multifaceted purification capabilities, GCS presents a promising alternative to SFs, especially in developing countries, aiming to improve water quality and ensure safe drinking water access. To the best of our knowledge, no other work groups the available research on GCS. Furthermore, future research directions should focus on reducing the overall production cost of GCS, exploring surface modification techniques, and expanding the range of contaminants tested by GCS, to fully realize its potential in water purification.

Squamous Carcinoma of the Oral Cavity in Patient with Fanconi Anemia: A Challenging Reconstruction with Double-barrel Free Fibula Flap Case Report.

Fanconi anemia (FA) is a very rare form of aplastic anemia. Patients with FA have a higher risk of developing solid tumors such as head and neck squamous cell carcinoma, higher risk of local recurrence, and impaired resistance to chemotherapy and radiotherapy treatments than the normal population. In this article, we describe the challenging clinical case of a patient with FA who underwent surgery for the removal of a large squamous cell carcinoma in the oral cavity. Mandibular reconstruction was performed using a biaxial double-barrel fibular flap, with excellent functional aesthetic outcomes.

Interplay of legacy irrigation and nitrogen fertilizer inputs to spatial variability of arsenic and uranium within the deep vadose zone.

The vadose zone is a reservoir for geogenic and anthropogenic contaminants. Nitrogen and water infiltration can affect biogeochemical processes in this zone, ultimately affecting groundwater quality. In this large-scale field study, we evaluated the input and occurrence of water and nitrogen species in the vadose zone of a public water supply wellhead protection (WHP) area (defined by a 50-year travel time to groundwater for public supply wells) and potential transport of nitrate, ammonium, arsenic, and uranium. Thirty-two deep cores were collected and grouped by irrigation practices: pivot (n = 20), gravity (n = 4) irrigated using groundwater, and non-irrigated (n = 8) sites. Beneath pivot-irrigated sites, sediment nitrate concentrations were significantly (p < 0.05) lower, while ammonium concentrations were significantly (p < 0.05) higher than under gravity sites. The spatial distribution of sediment arsenic and uranium was evaluated against estimated nitrogen and water loading beneath cropland. Irrigation practices were randomly distributed throughout the WHP area and presented a contrasting pattern of sediment arsenic and uranium occurrence. Sediment arsenic correlated with iron (r = 0.32, p < 0.05), uranium negatively correlated to sediment nitrate (r = -0.23, p < 0.05), and ammonium (r = -0.19 p < 0.05). This study reveals that irrigation water and nitrogen influx influence vadose zone geochemistry and mobilization of geogenic contaminants affecting groundwater quality beneath intensive agricultural systems.

Quality and hydrochemical assessment of groundwater in geological transition zones: a case study from N.E. Nigeria.

Sustainable management of groundwater resources in geological transition zones (GTZ) is essential due to their complex geology, increasing population, industrialization, and climate change. Groundwater quality monitoring and assessment represent a viable panacea to this problem. Therefore, there is a great need to investigate groundwater resources in terms of their chemistry and pollution to ascertain their quality and implement robust pollution abatement strategies. This study focused on the characterization of groundwater in a typical geological transition zone in northeastern Nigeria. Eighty-seven (87) groundwater samples were collected from dug wells and boreholes during the 2017 dry season. pH, conductivity, and total dissolved solids (TDS) were measured in situ using a multiparameter probe, while major cations and anions were measured using atomic absorption spectrometry and ion chromatography, respectively. Data were analyzed using descriptive statistics, principal component analysis (PCA), water quality index, and standard hydrochemical plots. TDS ranged between 95 and 1154 mg L-1 in basement terrains and between 49 and 1105 in sedimentary areas. pH ranged between 6.8 and 7.7 mg L-1 in basement terrains and between 5.0 and 6.5 in sedimentary areas, suggesting a moderately acidic to alkaline low mineralized groundwater. Calcium (2.6-128.0 mg L-1) was the dominant cation in the basement areas, suggesting silicate weathering/dissolution, while sodium (1.9-106.0 mg L-1) dominated the sedimentary zones due to base exchange reactions. The PCA analysis suggests that mineral dissolution (mostly silicate weathering) controls the hydrochemistry of the basement aquifers, while ion exchange and albite weathering, with some influence of anthropogenic factor, control the sedimentary aquifers. The water quality index revealed that the basement setting was predominated by poor to unsuitable groundwater, while the sedimentary terrain was characterized by potable groundwater. The dominant hydrochemical facie in the basement areas was Ca2+-(Mg2+)-HCO3- characteristic of recharge meteoric water. The Na+- (K+)-HCO3- facie characterized the sedimentary zones, indicative of cation exchange reactions, while the mixed water facie typifies the geological contact zones. The shallow nature of the basement groundwaters makes them more susceptible to geogenic and anthropogenic pollution compared to the sandstone aquifers. However, the basement aquifers have better irrigation indices (Kelly ratio and soluble sodium percent) as compared to the sandstone aquifers, which exhibit poor Kelly ratios (< 1) and soluble sodium percent (> 50) ratings. Results from the study clearly highlight the poor-unsuitable groundwater quality in parts of the studied GTZ and can be very instrumental to the policymakers in implementing sustainable water treatment strategies and cleaner production technologies in GTZ to forestall the incidence of water-related diseases.

Monitoring water quality through citizen science while teaching STEM undergraduate courses during a global pandemic.

Due to the COVID-19 pandemic, many universities struggle to engage students while implementing a distance-based teaching/learning approach and to provide hands-on activities to students enrolled in STEM classes. Implementing service-focused activities that can be conducted by the students remotely can overcome these struggles. The goals of this study were to 1) implement citizen science activities focused on water quality using three commercially available low-cost test strips (2:1, 5:1, and 16:1) while teaching four undergraduate engineering courses at the University of Mississippi (UM) during a pandemic event, and 2) evaluate the acceptability and validate the results obtained. Eighty-five undergraduate students (citizen scientists) and five research scientists (control group) collected two water samples (with triplicates) after receiving detailed step-by-step written guidelines and video tutorials. One hundred twenty tap water samples were collected from private households across Lafayette County and its surrounding counties and multiple buildings on campus. Five laboratory fortified blank (LBF) samples were implemented to validate the results. While the academic background of the participants did not impact the results (p > 0.05), the results obtained using the different test strips were statistically different (p < 0.05). In fact, results obtained using the 2:1 and the 5:1 test strips were close to the LFBs, while, except for the higher concentration of Total Alkalinity (40 mg/L CaCO3), results obtained using the 16:1 test strips were significantly different than the LFBs. Results (in terms of pH, Nitrate, and Total Chlorine) obtained by the citizen scientists using the 2:1 and 5:1 test strips were consistent with those reported in the annual drinking water quality reports from UM and municipalities included in the investigated region. Overall, this activity was well received by the students. Approximately 75% of them agreed that this hands-on activity was a positive experience while struggling to attend face-to-face classes.

Nitrogen removal in vermifiltration: Mechanisms, influencing factors, and future research needs.

To meet global health and sanitation goals, there is a continued need for sustainable wastewater treatment alternatives that require minimal energy and investment. Vermifiltration, a technology gaining relevance in Africa and Asia, may be an alternative to traditional wastewater treatment systems due to its cost-effectiveness, ease of application and maintenance, and sustainability. However, nitrogen removal in vermifiltration is not well understood since most of the prior research focuses on organics removal. Thus, a state of the art review is necessary to separately focus on the mechanisms associated with nitrogen removal in vermifiltration, along with the factors affecting nitrogen removal. For the first time, this review attempts to present the types of vermifilter based on their flow pattern. The review further discusses the current status of the application of vermifiltration, along with the benefits and limitations associated with the adoption of this technology. It also explores possible strategies that could be adopted to maximize the nitrogen removal potential of vermifilters as optimizing nitrogen removal is critical for improving the performance of vermifiltration based treatment systems.

Detection, occurrence, and fate of emerging contaminants in agricultural environments (2020).

A review of 79 papers published in 2019 is presented. The topics ranged from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, antibiotics, anthelmintics, and engineered nanomaterials in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Antibiotics in Agroecosystems, Pharmaceutical Fate and Occurrence, Anthelmintics and Engineered Nanomaterials. PRACTITIONER POINTS: New research describes innovative new techniques for emerging contaminant detection in agricultural settings Newer classes of contaminants include human and veterinary pharmaceuticals Research in nanomaterials show that these also occur in agricultural environments and will likely be topics of future work.

Detection, occurrence, and fate of emerging contaminants in agricultural environments (2019).

A review of 82 papers published in 2018 is presented. The topics ranged from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, microplastics, and engineered nanomaterials in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Fate and Occurrence, Pharmaceutical Metabolites, Anthelmintics, Microplastics, and Engineered Nanomaterials. PRACTITIONER POINTS: New research describes innovative new techniques for emerging contaminant detection in agricultural settings. Newer classes of contaminants include human and veterinary pharmaceuticals. Research in microplastics and nanomaterials shows that these also occur in agricultural environments and will likely be topics of future work.

Environmental fate and microbial effects of monensin, lincomycin, and sulfamethazine residues in soil.

The impact of commonly-used livestock antibiotics on soil nitrogen transformations under varying redox conditions is largely unknown. Soil column incubations were conducted using three livestock antibiotics (monensin, lincomycin and sulfamethazine) to better understand the fate of the antibiotics, their effect on nitrogen transformation, and their impact on soil microbial communities under aerobic, anoxic, and denitrifying conditions. While monensin was not recovered in the effluent, lincomycin and sulfamethazine concentrations decreased slightly during transport through the columns. Sorption, and to a limited extent degradation, are likely to be the primary processes leading to antibiotic attenuation during leaching. Antibiotics also affected microbial respiration and clearly impacted nitrogen transformation. The occurrence of the three antibiotics as a mixture, as well as the occurrence of lincomycin alone affected, by inhibiting any nitrite reduction, the denitrification process. Discontinuing antibiotics additions restored microbial denitrification. Metagenomic analysis indicated that Proteobacteria, Bacteroidetes, Actinobacteria, and Chloroflexi were the predominant phyla observed throughout the study. Results suggested that episodic occurrence of antibiotics led to a temporal change in microbial community composition in the upper portion of the columns while only transient changes occurred in the lower portion. Thus, the occurrence of high concentrations of veterinary antibiotic residues could impact nitrogen cycling in soils receiving wastewater runoff or manure applications with potential longer-term microbial community changes possible at higher antibiotic concentrations.

Detection, Occurrence and Fate of Emerging Contaminants in Agricultural Environments.

A total of 75 papers published in 2017 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, steroids, antibiotic resistance genes, and engineered nanoparticles agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Fate and Occurrence, Pharmaceutical Metabolites, Anthelmintics, Antibiotic Resistence Genes, and Engineered Nanomaterials.

Occurrence and removal of pharmaceutical compounds and steroids at four wastewater treatment plants in Hawai'i and their environmental fate.

The occurrence of pharmaceutical and steroid compounds in groundwater due to wastewater reuse has been reported and is of concern in tropical islands which primarily rely on groundwater. The objective of this study was to investigate the occurrence and removal of 43 pharmaceutical and steroid compounds detected in wastewater at four different wastewater treatment plants (WWTPs) in Hawai'i and to understand their environmental behavior through tropical soils as the treated effluents are used in landscapes for irrigation. Eight soil sampling locations, collected at three different depths, representing the most common soil types in Hawai'i and four WWTPs located across the major Hawaiian Islands were used. Disturbed soil samples were used to conduct the soil sorption and degradation studies and to estimate the leaching risk associated to the identified compounds. Quantification of selected compounds was conducted using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Among the investigated compounds, only ten were detected in the treated effluents at concentrations ranging from 0.004 to 0.900 µg L-1. Caffeine (64 µg L-1) and ibuprofen (96.5 µg L-1) showed the highest concentration in raw samples, while diphenhydramine (0.9 µg L-1) showed the highest concentration in treated effluent samples. Sulfamethoxazole showed the lowest removal (0-75%). Several pharmaceuticals showed consistently higher sorption capacity and longer persistency compared with steroids regardless of soil types and depths. Poamoho (Oxisol soil) and Waimanalo (Mollisol soil) showed the highest sorption capacity, while Waimea (Entisol soil) showed the lowest sorption capacity. Soil physico-chemical properties (i.e., clay content, level of organic carbon, and presence of metal oxide) and soil depth highly impacted the sorption behavior of the selected pharmaceutical compounds. In particular, the sorption capacity decreased with soil depth due to the higher level of organic carbon present in the first 30 cm compared with the deeper depths (60-90 cm).

A Tier-I leaching risk assessment of three anticoagulant compounds in the forested areas of Hawai'i.

The anticoagulant rodenticides brodifacoum, chlorophacinone, and diphacinone have been proposed for broadcast application in some forested areas in Hawai'i to protect rare and endangered native bird species from introduced mice and rats. Groundwater resources in Hawai'i are prone to contamination due to the intrinsic aquifer vulnerability to leaching from the land surface. Because of the hydrogeologic complexity, Hawai'i uses a Tier-I leaching assessment tool, CLERS, to make registration decisions for new or existing chemicals. The CLERS tool uses soil and pesticide properties as well as water recharge through the soil profile in a GIS framework to estimate mass attenuation of the chemicals at a given depth and compares against this attenuation factor against those of a known leacher and a non-leacher. Disturbed soil samples were collected across the state of Hawai'i, including the islands of Hawai'i, Kaho'olawe, Kaua'i, Lana'i, Maui, Moloka'i, and O'ahu, with two sampling locations per island, except for Kaua'i which had three. As only limited information on chemical properties of these anticoagulants in soils is available, laboratory experiments were performed to determine the sorption capacity (Kd) and the degradation rate (T1/2) of brodifacoum, chlorophacinone, and diphacinone to construct a proper chemical database. Depending on the soil type, T1/2 values ranged between 37 and 248days for diphacinone, between 39 and 1000days for chlorophacinone, and between 72 and 462days for brodifacoum. These data were used in the CLERS tool to estimate leaching risks for these chemicals primarily in forested areas of the state where the chemicals are likely to be applied. The results from the CLERS tool indicate low risks of leaching of these three compounds into aquifers in five out of six major Hawaiian Islands. Diphacinone showed medium risk of leaching in a few remote areas in Maui.

Detection, Occurrence and Fate of Emerging Contaminants in Agricultural Environments.

A total of 79 papers published in 2016 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, steroids, antibiotic resistance genes, cyanotoxins, and potential effects of biochar use in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Steroid Hormones, Anthelmintics, Antibiotic Fate and Occurrence, Antibiotic Resistance Genes, Cyanotoxins, and Implications of Biochar in Agricultural Environments.

Detection, Occurrence and Fate of Emerging Contaminants in Agricultural Environments.

A total of 59 papers published in 2015 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, steroids, antibiotic resistance genes in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Steroid Hormones, Pharmaceutical Contaminants, Transformation Products, and "Antibiotic Resistance, Drugs, Bugs and Genes".

Oxidative Stress Mediates the Antiproliferative Effects of Nelfinavir in Breast Cancer Cells.

The discovery of the anti-proliferative activity of nelfinavir in HIV-free models has encouraged its investigation as anticancer drug. Although the molecular mechanism by which nelfinavir exerts antitumor activity is still unknown, its effects have been related to Akt inhibition. Here we tested the effects of nelfinavir on cell proliferation, viability and death in two human breast cancer cell lines and in human normal primary breast cells. To identify the mechanism of action of nelfinavir in breast cancer, we evaluated the involvement of the Akt pathway as well as the effects of nelfinavir on reactive oxygen species (ROS) production and ROS-related enzymes activities. Nelfinavir reduced breast cancer cell viability by inducing apoptosis and necrosis, without affecting primary normal breast cells. The antitumor activity of nelfinavir was related to alterations of the cell redox state, coupled with an increase of intracellular ROS production limited to cancer cells. Nelfinavir treated tumor cells also displayed a downregulation of the Akt pathway due to disruption of the Akt-HSP90 complex, and subsequent degradation of Akt. These effects resulted to be ROS dependent, suggesting that ROS production is the primary step of nelfinavir anticancer activity. The analysis of ROS-producers and ROS-detoxifying enzymes revealed that nelfinavir-mediated ROS production was strictly linked to flavoenzymes activation. We demonstrated that ROS enhancement represents the main molecular mechanism required to induce cell death by nelfinavir in breast cancer cells, thus supporting the development of new and more potent oxidizing molecules for breast cancer therapy.

Detection, Occurrence and Fate of Emerging Contaminants in Agricultural Environments.

A total of 43 papers published in 2014 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to measuring and predicting biological effects for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, natural and synthetics steroids, and antibiotic resistance genes in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Occurrence and Fate, Antibiotic Resistance Genes, and Risk Assessment.

Pharmaceutically active compounds: Their removal during slow sand filtration and their impact on slow sand filtration bacterial removal.

Slow sand filtration (SSF) has been widely used as a means of providing potable water due to its efficacy, low cost, and minimal maintenance. Advances in analytical instrumentation have revealed the occurrence of pharmaceutically active compounds (PhACs) in surface water as well as in groundwater. It is unclear if the presence of these compounds in the feed water can interfere with the performances of an SSF unit. The aim of this work was to examine i) the ability of two SSF units to remove six PhACs (caffeine, carbamazepine, 17-ß estradiol [E2], estrone [E1], gemfibrozil, and phenazone), and ii) the impact of these PhACs on the removal of bacteria by two SSF units. The presence of PhACs in feed water for SSF can occur in surface waters impacted by wastewater or leakage from sewers and septic tanks, as well as in developing countries where unregulated use and improper disposal are prevalent. Two pilot-scale SSF units were used during the study. Unit B1 was fed with stream water with 1% of primary effluent added, while unit B2 was fed with stream water alone. Although limited removal (<10%) of carbamazepine, gemfibrozil, and phenazone occurred, the complete removal of caffeine, and the partial removal (11-92%) of E2 and E1 were observed in the two SSF units. The results of this study suggest that the occurrence of the selected PhACs, probably estrogens and caffeine, in the feed water at 50 µg L(-1) affected the ability of the schmutzdecke to remove total coliform and Escherichia coli. The bacterial removal achieved within the schmutzdecke dropped from 95% to less than 20% by the end of the study. This decrease in removal may be related to the change in the microbial community within the schmutzdecke. A diverse microbial community, including Bacteroidetes and several classes of Proteobacteria, was replaced by a microbial community in which Gammaproteobacteria was the predominant phylum (99%). Despite the low removal achieved within the schmutzdecke, removal of total coliform and E. coli greater than 99% occurred after both SSF units throughout the study. Bacterial removal occurred in the upper half of the sand filter. This was probably due to a diverse microbial community established in the packing material, in which Bacteroidetes (13-25%), Acidobacteria (7-17%) and several classes of Proteobacteria (35-52%) (Alpha-, Beta-, Delta-, and Gammaproteobacteria) were the predominant phyla.

Fate of selected pharmaceutically active compounds during simulated riverbank filtration.

The objective of this study was to investigate the effect of temperature, oxygen, and organic matter on the removal of selected pharmaceutically active compounds (PhACs) during simulated riverbank filtration (RBF). The behavior of six PhACs (caffeine, carbamazepine, 17-ß estradiol [E2], estrone [E1], gemfibrozil, and phenazone) was evaluated by small flow-through column experiments. Results from our study showed that RBF can be used to treat many of the PhACs found in environmental waters. Local conditions at the RBF site, however, can affect the removal of PhACs and should be investigated. Biodegradation and sorption represented the predominant mechanisms involved during the removal of the selected PhACs. All selected PhACs showed limited and slower removal during the winter. Phenazone was highly impacted by the level of oxygen; complete depletion of phenazone below the analytical limit occurred only under aerobic conditions (dissolved oxygen >8 mg L(-1)). Caffeine and E2 were highly impacted by the presence of humic acid in the feed water. Caffeine and E2 were depleted below the detection limit in the presence of humic acid regardless of the temperature and the level of oxygen. E1 was impacted by the different environmental conditions and depletion below the detection limit occurred only during the summer under aerobic conditions. Carbamazepine (10%) and gemfibrozil (<30%) showed limited removal regardless of the different levels of temperature, oxygen and humic acid.