Ecotoxicological effects, environmental fate and risks of pharmaceutical and personal care products in the water environment: A review

Nanoengineered metal-organic framework for adsorptive and photocatalytic mitigation of pharmaceuticals and pesticide from wastewater

Rapidly expanding water pollution has transformed into significant dangers around the world. In recent years, the pharmaceutical and agriculture field attained enormous progress to meet the necessities of health and life; however, discharge of trace amounts of pharmaceuticals and pesticides into water significantly have a negative influence on human health and the environment. Contamination with these pollutants also constitutes a great threat to the aquatic ecosystem. To deal with the harmful impacts of such pollutants, their expulsion has attracted researchers' interest a lot, and it became essential to figure out techniques suitable for the removal of these pollutants. Thus, many researchers have devoted their efforts to improving the existing technology or providing an alternative strategy to solve this environmental problem. One of the attractive materials for this purpose is metal-organic frameworks (MOFs) due to their superior high surface area, high porosity, and the tunable features of their structures and function. Among various techniques of wastewater treatment, such as biological treatment, advanced oxidation process and membrane technologies, etc., metal-organic frameworks (MOFs) materials are tailorable porous architectures and are viably used as adsorbents or photocatalysts for wastewater treatment due to their porosity, tunable internal structure, and large surface area. MOFs are synthesized by various methods such as solvo/hydrothermal, sonochemical, microwave and mechanochemical methods. Most common method used for the synthesis of MOFs is solvothermal/hydrothermal methods. Herein, this review aims at providing a comprehensive overview of the latest advances in MOFs and their derivatives, focusing on the following aspects: synthesis and applications. This review comprehensively highlights the application of MOFs and nano-MOFs to remove pharmaceuticals and pesticides from wastewater. For the past years, transition metal-based MOFs have been concentrated as photocatalyst/adsorbents in treating contaminated water. However, work on main group metal-based MOFs is not so abundant. Hence, the foremost objective of this review is to present the latest material and references concerning main group element-based MOFs and nanoscale materials derived from them towards wastewater treatment. It summarizes the possible research challenges and directions for MOFs and their derivatives as catalysts applied to wastewater treatment in the future. With the context of recent pioneering studies on main group elements-based MOFs and their derivatives; we hope to stimulate some possibilities for further development, challenges and future perspectives in this field have been highlighted.

First report on the occurrence of pharmaceuticals and cocaine in the coastal waters of Santa Catarina, Brazil, and its related ecological risk assessment

The worldwide occurrence of pharmaceuticals and personal care products (PPCPs) in aquatic ecosystems is reason for public concern. These emerging micropollutants include a large and diverse group of organic compounds, with continuous input, high environmental persistence and potential threat to biota and human health. The aim of this study was to evaluate, for the first time, the occurrence of twenty-seven PPCPs of various therapeutic classes (including cocaine and its primary metabolite, benzoylecgonine), in the coastal waters of Santa Catarina, southern Brazil. Water samples were taken in November 2020, during the low tide periods, at eight sampling points located along the coast of Santa Catarina, covering its entire geographical extension. Sampling was carried out in triplicate and at different depths of the water column. Nine compounds were detected through liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS): caffeine (12.58-119.80 ng/L), diclofenac (1.34-7.92 ng/L), atenolol (1.13-2.50 ng/L), losartan (0.43-3.20 ng/L), acetaminophen (0.21-10.04 ng/L), orphenadrine (0.07-0.09 ng/L), cocaine (0.02-0.17 ng/L), benzoylecgonine (0.01-1.1 ng/L) and carbamazepine (0.02-0.27 ng/L). The highest occurrence of these compounds was detected in the northern and central coastal region of Santa Catarina, namely in Penha and Palhoça cities. Moreover, the risk assessment showed that almost compounds (atenolol, benzoylecgonine, carbamazepine, cocaine and orphenadrine) presented no ecological risk in the recorded concentrations. However, a few compounds suggest low (caffeine and diclofenac) to moderate (acetaminophen and losartan) risk taking into consideration the acute and chronic effects for the three trophic levels (algae, crustacean and fish) tested. These compounds are usually found in areas with high population density, aggravated by tourism, because of the sanitary sewage and solid waste. Although in low concentrations, the occurrence of these chemical compounds can imply deleterious effects on the environmental health of Santa Catarina coastal zone, and therefore deserve more attention by the public authorities and environmental agencies.

Occurrence, hazard, and risk of psychopharmaceuticals and illicit drugs in European surface waters

This study aimed to provide insights into the risk posed by psychopharmaceuticals and illicit drugs in European surface waters, and to identify current knowledge gaps hampering this risk assessment. First, the availability and quality of data on the concentrations of psychopharmaceuticals and illicit drugs in surface waters (occurrence) and on the toxicity to aquatic organisms (hazard) were reviewed. If both occurrence and ecotoxicity data were available, risk quotients (risk) were calculated. Where abundant ecotoxicity data were available, a species sensitivity distribution (SSD) was constructed, from which the hazardous concentration for 5% of the species (HC₅) was derived, allowing to derive integrated multi-species risks. A total of 702 compounds were categorised as psychopharmaceuticals and illicit drugs based on a combination of all 502 anatomical therapeutic class (ATC) 'N' pharmaceuticals and a list of illicit drugs according to the Dutch Opium Act. Of these, 343 (49%) returned occurrence data, while only 105 (15%) returned ecotoxicity data. Moreover, many ecotoxicity tests used irrelevant endpoints for neurologically active compounds, such as mortality, which may underestimate the hazard of psychopharmaceuticals. Due to data limitations, risks could only be assessed for 87 (12%) compounds, with 23 (3.3%) compounds indicating a potential risk, and several highly prescribed drugs returned neither occurrence nor ecotoxicity data. Primary bottlenecks in risk calculation included the lack of ecotoxicity data, a lack of diversity of test species and ecotoxicological end points, and large disparities between well studied and understudied compounds for both occurrence and toxicity data. This study identified which compounds merit concern, as well as the many compounds that lack the data for any calculation of risk, driving research priorities. Despite the large knowledge gaps, we concluded that the presence of a substantial part (26%) of data-rich psychopharmaceuticals in surface waters present an ecological risk for aquatic non-target organisms.

Effective adsorption of diclofenac and naproxen from water using fixed-bed column loaded with composite of heavy sugarcane ash and polyethylene terephthalate

The contamination of water by pharmaceutical pollutants is a major issue these days due to excessive use of these ingredients in modern life. This study evaluated the adsorption and effectiveness of a low-cost composite prepared from heavy sugarcane ash (HSA) fused with polyethylene terephthalate (PET) and functionalized with iron (Fe³⁺) in a dynamic system through a fixed-bed column. The solution of synthetic drugs was prepared and placed in a reservoir, using a peristaltic pump the solution is run onto the fixed bed column at a flow rate of 2 mL min^-1. Saturation time and adsorption capacity were evaluated by centrifugation and extraction after a regular interval of 2 h from the adsorption column. The samples were analyzed using high-performance liquid chromatography (HPLC) and the data was modeled for quantification. For DIC removal, an adsorption capacity of 324.34 μg. g^-1 and a saturation time of 22 h were observed, while the adsorption capacity of NAP was 956.49 μg. g^-1, with a saturation time of 8 h. Thus, the PETSCA/Fe³⁺ adsorbent proved to be quite efficient for removing the pharmaceutical pollutants, with a longer period of operation for DIC removal. These findings suggested that a highly efficient bed column made from a less expensive waste material and could be used to remove hazardous pharmaceutical contaminants.

Pharmaceutical and personal care products as emerging environmental contaminants in Nigeria: A systematic review

The increasingly broad and massive use of pharmaceuticals (human, veterinary) and personal care products in industrially developing nations makes their uncontrolled environmental and ecological impact a true concern. Focusing on Nigeria, this systematic literature search (databases: PubMed, ScienceDirect, Google Scholar, EMBASE, Scopus, Cochrane library and African Journals Online) aims to increase visibility to the issue. Among 275 articles identified, 7 were included in this systematic review. Studies indicated the presence of 11 personal care products (15.94 %) and 58 pharmaceutical products (84.06 %) in surface and ground water, leachates, runoffs, sludge, and sediments. The 42.86% (3/7) of reviewed studies reported 17 analgesics; 71.42 % (5/7) reported 16 antibiotics; 28.57 % (2/7) reported 5 lipid lowering drugs; 28.57% reported anti-malaria and fungal drugs; 14.29 % (1/7) reported estrogen drugs. Different studies report on sunscreen products, hormone, phytosterol, insect repellent, and β1 receptor. Gemfibrozil (<4-730 ng/L), Triclosan (55.1-297.7 ng/L), Triclocarban (35.6-232.4 ng/L), Trimethoprim (<1-388 ng/L) and Tramadol (<2-883 ng/L) had the highest range of concentrations. Findings confirm the need of i) legislation for environmental monitoring, including biota, ii) toxicological profiling of new market products, and iii) sensitization on appropriate use and disposal of pharmaceuticals and personal care products.

Characterization and Ofloxacin Adsorption Studies of Chemically Modified Activated Carbon from Cassava Stem

Cassava is a type of crop popular in Asian countries. It can be easily cultivated and grows to a mature plant in 9 months. Considering its availability, this work studied activated carbon based on cassava stem. Ofloxacin was chosen as the adsorbate, simulating the wastewater from the pharmaceutical industry. Cassava stem was ground into particles and heated to the activated state, 787 °C. The cassava-stem-activated carbon was further treated with the surface modifier, namely sodium hydroxide and zinc chloride, to study the improvement in ofloxacin adsorption. Prepared adsorbents were characterised using the SEM, FT-IR, XRD, DSC and TGA methods before being evaluated through batch adsorption, thermodynamic, and kinetic studies. The surface area analysis indicates that treatment of the activated carbon with NaOH and ZnCl₂ increases the surface area due to the removal of organic content by the chemicals. Better ofloxacin adsorption of all activated carbon samples can be obtained with solutions at pH 8. An endothermic reaction was predicted, shown by higher ofloxacin adsorption at a higher temperature, supported by a positive value of ΔH° in the thermodynamic studies. The negative values of ΔG° revealed that adsorptions were spontaneous. The higher R² values indicate that the adsorption process follows the pseudo-second-order equation of kinetic study. The maximum adsorption capacities are 42.37, 62.11, 62.89 and 58.82 mg/g for raw cassava stem (RC), cassava-stem-activated carbon (AC), NaOH-modified cassava-stem-activated carbon (NAC), and ZnCl₂ modified cassava-stem-activated carbon (ZAC). The adsorption capacity is good compared to previous works by other researchers, making it a possible alternative material for the pharmaceutical industry’s wastewater treatment.

Highly Effective Removal of Ofloxacin from Water with Copper-Doped ZIF-8

Residual antibiotics in wastewater have gained widespread attention because of their toxicity to humans and the environment. In this work, Cu-doped ZIF-8s (Cu-ZIF-8s) were successfully synthesized by the impregnation of Cu²⁺ in ZIF-8 and applied in the removal of ofloxacin (OFX) from water. Remarkably, excellent adsorption performance was obtained in Cu-ZIF-8s, especially for Cu-ZIF-8-1, in which the adsorption capacity (599.96 mg·g⁻¹) was 4.2 times higher than that of ZIF-8 and superior to various adsorbents reported previously. The adsorption kinetics and adsorption isotherm follow the pseudo-second-order model and the Langmuir model, respectively. Furthermore, the removal efficiencies of OFX in Cu-ZIF-8-1 reached over 90% at low concentrations. It was revealed that electrostatic interaction and complexation play important roles in the adsorption process. In addition, the material can be regenerated by simple methods. Therefore, the obtained Cu-doped MOFs may have a promising application in the treatment of antibiotic-containing wastewater.

Metabolomic analysis of Scenedesmus obliquus reveals new insights into the phytotoxicity of imidazolium nitrate ionic liquids

Due to the persistence of ionic liquids (ILs) in aquatic environments, it is necessary to reveal their ecological risk to aquatic organisms. Herein, the biotoxicity of two alkyl-methylimidazolium nitrate ILs ([C₁₀mim]NO₃ and [C₁₂mim]NO₃) against Scenedesmus obliquus were studied. Results showed that the growth inhibition of S. obliquus increased with increasing concentrations of ILs, maximum values of 94.61% at 4 mg/L of [C₁₀mim]NO₃ and 97.34% at 0.8 mg/L of [C₁₂min]NO₃ were observed. The fluorescence parameters of photosystem II, such as light quantum yield and electron transfer rate, showed a negative relationship with the exposure dose. [C₁₂mim]NO₃ had a more significant effect than [C₁₀mim]NO₃. Moreover, the redox homeostasis of algae was disrupted; the accumulation of reactive oxygen species, leading to obvious inhibition of superoxide dismutase and catalase activities was observed. A metabolomic analysis indicated that the contents of most metabolites were reduced significantly, and fructose and galactose decreased significantly by 42.3% and 88.6%, respectively, in the [C₁₀mim]NO₃ treatment compared to those in the control. The inhibition of amino acid biosynthesis and glyoxylate and dicarboxylate metabolism explained the more serious biotoxicity of [C₁₂mim]NO₃ than that of [C₁₀mim]NO₃. This study facilitates a better understanding of the environmental safety and ecological risks of ILs.

Environmental antibiotics exposure in school-age children in Shanghai and health risk assessment: A population-based representative investigation

BACKGROUND

The widespread use of antibiotics has left extensive residues in the environment and food. Antibiotics can accumulate in human body. As the potential health risks of antibiotic exposure in children are of a great concern in recent years, our study aimed to describe the status of antibiotic exposure in primary school students in Shanghai, China, and to explore the relationships of dietary patterns with internal antibiotic levels.

METHODS

The Shanghai Children's Health, Education, and Lifestyle Evaluation (SCHEDULE) Survey was a cross-sectional study with a staged, cluster random sample of all primary school students in Shanghai, China. In the present study, we randomly selected 2199 children aged 6-12 years old. A total of 10 antibiotics in urine samples were measured by liquid chromatography-tandem mass spectrometry. Multivariable survey logistic regression models were used to investigate dietary patterns associated with detection rates of antibiotics.

RESULTS

The detection rates of individual antibiotics ranged from 4.3% to 30.7%. 68.7% of children were exposed to at least one antibiotic. There was a significant difference in child exposure to overall antibiotics by residential locations (60.9% in urban vs. 71.1% in suburban areas). Principal component analyses suggested that higher unhealthy dietary pattern scores were significantly associated with increased detection rates of tetracyclines [1.27 (95% CI: 1.18, 1.38)] and sulfonamides [1.20 (95% CI: 1.05, 1.36)]. In addition, 9.05% of children had a hazard index (HI) value greater than 1, which was mainly contributed by ciprofloxacin.

CONCLUSIONS

School-age children were widely exposed to antibiotics in Shanghai. Unhealthy diet was associated with a higher level of antibiotic exposure.

Design and application of molecularly imprinted polymers for adsorption and environmental assessment of anti-inflammatory drugs in wastewater samples

In this study, a series of molecularly imprinted polymers (MIPs) have been synthesized using separately diclofenac, naproxen, and ibuprofen as templates with three different polymerization approaches. Two functional monomers, methacrylic acid (MAA) and 2-vinylpyridine (2-VP), were tested and ethylene glycol dimethacrylate (EGDMA) was used as crosslinker; also, template-free polymers (NIPs) were synthesized. It was found that the MIP with the highest retention percentage for diclofenac was the one prepared by the emulsion approach and with MAA (98.3%); for naproxen, the one prepared by the bulk polymerization with MAA (99%); and for ibuprofen, the one synthesized by bulk with 2-VP (97.7%). These three MIPs were characterized by scanning electron microscopy, thermogravimetric test, Fourier transform infrared, specific area measurements, and surface charge. It was found that the emulsion method allowed particle size control, while the bulk method gave heterogeneous particles. The three evaluated MIPs exhibited thermal stability up to 300 °C, and it was observed that 2-VP confers greater stability to the material. From the BET analysis, it was demonstrated that the MIPs and NIPs evaluated are mesoporous materials with a pore size between 10 and 20 nm. In addition, the monomer influenced the surface charge of the material, since the MAA conferred an acidic point of zero charge (PZC), while the 2-VP conferred a PZC of basic character. Through adsorption isotherms, it was determined  that there is a higher adsorption capacity of the MIPs at acidic pH following a pseudo-second-order kinetic model. Finally, the MIPs were used to determine the non-steroidal anti-inflammatory drugs (NSAIDs) understudy in San Luis Potosí, México, wastewater, finding concentrations of 0.642, 0.985, and 0.403 mg L^-1 for DCF, NPX, and IBP, respectively.

Metagenomic ecotoxicity assessment of trace difenoconazole on freshwater microbial community

Difenoconazole, a typical triazole fungicide, inhibits the activity of cytochrome P450 enzyme in fungi, and is extensively used in protecting fruits, vegetables, and cereal crops. However, reports elucidating the effects of difenoconazole on aquatic microbial communities are limited. Our study showed that difenoconazole promoted microalgae growth at concentrations ranging from 0.1 to 5 μg/L, which was similar with its environmental residual concentrations. Metagenomic analysis revealed that the aquatic microbial structure could self-regulate to cope with difenoconazole-induced stress by accumulating bacteria exhibiting pollutant degrading abilities. In the short-term, several functional pathways related to xenobiotic biodegradation and analysis were upregulated to provide ability for aquatic microbial community to process xenobiotic stress. Moreover, most disturbed ecological functions were recovered due to the redundancy of microbial communities after prolonged exposure. Furthermore, the risks associated with the dissemination of antibiotic resistance genes were enhanced by difenoconazole in the short-term. Overall, our study contributes to a comprehensive understanding of the difenoconazole-induced ecological impacts and the behavior of aquatic microbial communities that are coping with xenobiotic stress.

Sedimentary spectrum and potential ecological risks of residual pharmaceuticals in relation to sediment-water partitioning and land uses in a watershed

Pharmaceutical residues in river surficial sediment are prone to anthropogenic impacts and environmental factors in watershed, but the mechanisms remain unclear. This study attempted to reveal surficial sediment-water pseudo-partitioning and anthropogenic (land use) patterns of pharmaceutical residues in surficial sediment among 23 subwatersheds of Jiulong River, southeast China with a gradient of urban land use percentile in dry and wet seasons. Thirty-eight out of target 86 compounds from six-category pharmaceuticals were quantified and ranged from below the quantification limits (0.001 mg kg^-1 dry mass) up to 8.19 mg kg^-1 dry mass (chlortetracycline) using a developed SPE-HPLC-MS/MS protocol. Antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) collectively dominated sedimentary pharmaceutical residues for 34.5-99.8% of the total quantified compounds (median at 92%). Land uses in subwatersheds showed high consistency with sedimentary pharmaceutical residues in the dry season rather than the wet season, especially for human use only and veterinary use only compounds. Surficial sediment-water partitioning of pharmaceutical compounds influenced their sedimentary residues regardless of season, which were determined by properties of compound and surficial sediment interactively. All tetracycline compounds, trimethoprim (sulfonamides synergist), caffeine (central nervous system drug), and oxfendazole (antiparasitic drug) were quantified to pose high potential ecological risks to aquatics. Findings of this study suggest that pseudo-persistent legacy of human and veterinary pharmaceuticals requires a wider coverage of pharmaceutical compounds for a comprehensive ecological assessment in the environment and more involvement of anthropogenic impacts and socioeconomic factors in the future studies.

Stable isotope probing reveals specific assimilating bacteria of refractory organic compounds in activated sludge

Activated sludge in wastewater treatment bioreactors contains diverse bacteria, while little is known about the community structure of bacteria responsible for degradation of refractory organic compounds (ROCs). In this study, 10 ROCs frequently detected in sewage were investigated, and the potential bacteria degrading these ROCs were analyzed by DNA stable isotope probing and high-throughput sequencing. The results showed that the bacterial communities responsible for degradation of different ROCs were largely different. A total of 84 bacterial genera were found to be involved in degrading at least one of the 10 ROCs, however, only six genera (Acinetobacter, Bacteroides, Bosea, Brevundimonas, Lactobacillus and Pseudomonas) were common to all 10 ROCs. This suggests that different ROCs may have specific assimilating bacteria in the activated sludge. Our results also showed that these ROC-degrading bacteria are difficult to isolate by conventional methods and that most of them have relatively low relative abundance in municipal wastewater treatment bioreactors. Development of new technologies to increase the abundance and activity of these bacteria may significantly improve the removal efficiency of ROCs from wastewater.

Experimental and theoretical study for removal of trimethoprim from wastewater using organically modified silica with pyrazole-3-carbaldehyde bridged to copper ions

BACKGROUND

Human and veterinary antibiotics are typically discharged as parent chemicals in urine or feces and are known to be released into the environment via wastewater treatment plants (WWTPs). Several research investigations have recently been conducted on the removal and bioremediation of pharmaceutical and personal care products (PPCPs) disposed of in wastewater.

RESULTS

SiNP-Cu, a chelating matrix, was produced by delaying and slowing 1.5-dimethyl-1H-pyrazole-3-carbaldehyde on silica gel from functionalized with 3-aminopropyltrimethoxysilane. The prepared sorbent material was characterized using several techniques including BET surface area, FT-IR spectroscopy, Scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and nitrogen adsorption-desorption isotherm. The pseudo-second-order model provided the best correlation due to the big match between the experimental and theoretical of different adsorption coefficients. The Langmuir and Freundlich adsorption models were used and the study showed a better match with the Freundlich model with a capacity of removal reached up to 420 mg g^-1. The removal capacity was dependent on pH and increased by increasing pH. The removal percentage reached 91;5% at pH = 8. The adsorbent demonstrated a high percentage removal of TMP, reaching more than 94% when increased pH. The sample was simply regenerated by soaking it for a few minutes in 1 N HCl and drying it. The sorbent was repeated five times with no discernible decrease in removal capacity. The thermodynamic study also showed endothermic, increasing randomness and not spontaneous. The free energy was 2.71 kJ/mol at 320 K. The findings of the DFT B3LYP/6-31 + g (d, p) local reactivity descriptors revealed that nitrogen atoms and π-electrons of the benzene and pyrimidine rings in the TMP are responsible for the adsorption process with the SiNP surface. The negative values of the adsorption energies obtained by molecular dynamic simulation indicated the spontaneity of the adsorption process.

CONCLUSION

The global reactivity indices prove that TMP is stable and it can be removed from wastewater using SiNP surface. The results of the local reactivity indices concluded that the active centers for the adsorption process are the nitrogen atoms and the π-electrons of the pyrimidine and benzene rings. Furthermore, the positive value of the maximum charge transfer number (ΔN) proves that TMP has a great tendency to donate electrons to SiNP surface during the process of adsorption.

Behavioral, physiological and biochemical responses and differential gene expression in Mytilus galloprovincialis exposed to 17 alpha-ethinylestradiol and sodium lauryl sulfate

Mixture of contaminants often determine biological responses of marine species, making difficult the interpretation of toxicological data. The pharmaceutical 17 alpha-ethinylestradiol (EE2) and the surfactant Sodium Lauryl Sulfate (SLS) commonly co-occur in the marine environment. This study evaluated the effects of EE2 (125.0 ng/L) and SLS (4 mg/L), acting individually and combined, in the mussel Mytilus galloprovincialis. Contaminated mussels closed their valves for longer periods than control ones, especially in the presence of both contaminants, with longer closure periods immediately after spiking compared to values obtained one day after spiking. Nevertheless, males and females increased their metabolism when in the presence of both contaminants (males) and SLS (females), and independently on the treatment males and females were able to activate their antioxidant and biotransformation defences. Although enhancing defences mussels still presented cellular damage and loss of redox balance, especially noticed in the presence of EE2 for males and SLS for females. Histopathological damage was found at mussel's gills in single and mixture exposure, and qPCR analysis revealed a clear estrogen receptor expression with no additive effect due to combined stressors. The results obtained highlight the harmful capacity of both contaminants but further research on this matter is needed, namely considering different climate change scenarios.

Insights into the spatiotemporal occurrence and mixture risk assessment of household and personal care products in the waters from rivers to Laizhou Bay, southern Bohai Sea

Household and personal care products (HPCPs) are a kind of contaminants closely related to daily life, capturing worldwide concern. To our knowledge, this is the first attempt focusing on the spatiotemporal occurrence and mixture risk of HPCPs in the waters from rivers to Laizhou Bay. Nine HPCPs were quantitated in 216 water samples gathered from Laizhou Bay and its adjacent rivers in 2018, 2019, and 2021 to reveal the spatiotemporal occurrence and mixture ecological risks in Laizhou Bay. Eight HPCPs were detected with detection frequencies ranging from 74% to 100%. The total concentrations were in the ranges 105-721 ng L^-1 in river water and 51.3-332 ng L^-1 in seawater. The HPCPs were dominated by p-hydroxybenzoic and triclosan, which together contributed over 75% of the total HPCPs. The average level of the total HPCP concentration in the summer of 2018 (96.1 ng L^-1) was slightly exceed that in the spring of 2019 (91.6 ng L^-1), which is associated with the higher usage of HPCPs and enhanced tourism during summer. However, the highest total concentrations were found in spring of 2021 (124 ng L^-1 in average), which was attribute to a higher level of methylparaben, a predominant paraben used as preservatives in commercial pharmaceuticals of China. Influenced by riverine inputs and ocean currents, higher HPCP concentrations in Laizhou Bay were found nearby the estuary of Yellow River and the southern part of the bay. Triclosan should be given constant concern considering its medium to high risks (RQ > 0.1) in nearly 80% of the water samples. The cumulative risk assessment in two approaches revealed that HPCP mixtures generally elicit medium or high risk to three main aquatic taxa. Considering the worldwide outbreak of COVID-19, the levels and risks of multiple HPCPs in natural waters requires constant attention in future studies.

Effects of ofloxacin on the structure and function of freshwater microbial communities

Ofloxacin (OFL) is a broad-spectrum fluoroquinolone antibiotic frequently used in clinic for treating bacterial infections. The discharged OFL would inevitably enter into aquatic ecosystems, affecting the growth of non-target microorganisms, which may result in micro-ecosystem imbalance. To the best of our knowledge, researches in this area are rather sparse. The present study evaluated the response of photosynthetic microorganisms (cyanobacteria, eukaryotic algae) and aquatic microbial community to OFL in a microcosm. Results showed that ofloxacin presented an inhibitory effect on the growth Microcystis aeruginosa. Although 0.1 mg/L OFL has no significant impact on alpha diversity of the microbial communities, it obviously altered the structure and decreased the species interaction of prokaryotic community by reducing the capacities of nitrogen fixation, photosynthetic and metabolic capacity of the microbial community. This study pointed out that the residual OFL in water would disturb the balance of the aquatic micro-ecology, suggesting that more attentions should be given to the negative effects of antibiotics and other bioactive pollutants on aquatic environments.

Enhancing the sensitivity of water toxicity detection based on suspended Shewanella oneidensis MR-1 by reversing extracellular electron transfer direction

Water toxicity detection is of great significance to ensure the safety of water supply. With suspended electrochemically active bacteria (EAB) as the sensing element, a novel microbial electrochemical sensor (MES) has recently been reported for the real-time detection of water toxicity, but its practical applications need to further improve the sensitivity. Extracellular electron transfer (EET) is an important factor affecting MES performance. In the study, the EET of suspended EAB-based MES was optimized to further enhance the sensitivity. Firstly, by using a model EAB stain Shewanella oneidensis MR-1, it was revealed that the sensitivity was increased at most 2.7 times with inward EET (i.e., cathodic polarization). Then, a novel conjecture based on electron transfer and energy fluxes was proposed and testified to explain this phenomenon. Finally, three key operating parameters of inward EET were orthogonally optimized. The optimized parameters of inward EET included a potential of - 0.5 V, a cell density of 1.8 × 10⁸ CFU/mL, and an electron acceptor concentration of 15 mM.

Fluoroquinolone antibiotics disturb the defense system, gut microbiome, and antibiotic resistance genes of Enchytraeus crypticus

Antibiotic residues from animal manure cause soil pollution and can pose a threat to soil animals. In this study, the toxicological effects of fluoroquinolone antibiotics on Enchytraeus crypticus, including defence response, gut microbiome, and antibiotic resistance genes (ARGs), were studied. The cytochrome P450 enzyme activity and reactive oxygen species levels increased, activating the defense response. The superoxide dismutase and glutathione S-transferase activity, and the expression of immune defense molecules such as coelomic cytolytic factor, lysozyme, bactericidal protein fetidins and lysenin changed. Furthermore, the diversity of the gut microbiome decreased, and the relative abundance of Bacteroidetes decreased significantly at the phylum level but increased in pathogenic and antibiotic-secreting bacteria (Rhodococcus and Streptomyces) at the genus level. However, the soil microbiome was not significantly different from that of the control group. The relative abundance of ARGs in the gut and soil microbiome significantly increased with enrofloxacin concentration, and the fluoroquinolone ARGs were significantly increased in both the soil (20.85-fold, p < 0.001) and gut (11.72-fold, p < 0.001) microbiomes. Subtypes of ARGs showed a positive correlation with Rhodococcus, which might increase the risk of disease transmission and the probability of drug-resistant pathogens. Furthermore, mobile genetic elements significantly promote the spread of ARGs.

Profiling of the spatiotemporal distribution, risks, and prioritization of antibiotics in the waters of Laizhou Bay, northern China

We investigated the spatiotemporal distributions, risks, and prioritization of 15 widely used antibiotics in Laizhou Bay (LZB). Water samples (145) were collected from LZB and its estuaries and analyzed. Twelve antibiotics, with total concentrations of 241-1450 and 69-289 ng L^-1 in estuarine water and seawater, respectively, were detected, with the contributions of norfloxacin, ciprofloxacin, and amoxicillin exceeding 70%. Amoxicillin was firstly determined, which contributed to 20% and 46% of the total antibiotics during summer and spring, respectively. Higher antibiotic concentrations were observed in the sea located adjacent to aquaculture bases and the Yellow River Estuary, which are significantly influenced by mariculture and riverine inputs, respectively. Veterinary antibiotics showed higher total concentrations in summer compared to spring, indicating a higher degree of their usage in mariculture in summer. The antibiotic mixtures posed high risk to algae and low to medium risks to crustaceans and fish. Amoxicillin and norfloxacin were identified as high-risk pollutants. Additionally, amoxicillin and ciprofloxacin showed medium to high resistance development risks. Previous studies on antibiotics in the LZB did not determined amoxicillin and thus underestimated antibiotic contamination, ecological risk, and resistance development risk. Amoxicillin, norfloxacin, and ciprofloxacin should be prioritized in risk management.

Heterogeneous Activation of Persulfate by LaMO3 (M=Co, Fe, Cu, Mn, Ni) Perovskite Catalysts for the Degradation of Organic Compounds

Sulfate radical-based advanced oxidation processes (SR-AOPs) are lately applied for the degradation of various pollutants through the formation of reactive oxidant species (ROS) from activation of oxidants, such as persulfate (PS) or peroxymonosulfate (PMS). In this study, LaMO3 (M=Co, Fe, Cu, Mn, Ni) perovskite catalysts were synthesized, characterized by several techniques, and tested for the activation of persulfate towards the degradation of phenolic pollutants. The effect of substitution of position B of La-based perovskites as well as calcination temperature was studied. Overall, the results showed that the decisive role in the catalytic activity was the presence of structures that enhance the transfer of electrons between perovskite and oxidant. LaNiO3 followed by LaCoO3 were found as the most active catalysts. Finally, the stability of the catalysts was studied, showing that B-metal leaching is significant for both catalysts, with LaCoO3 being the most stable one.

Enrofloxacin perturbs nitrogen transformation and assimilation in rice seedlings (Oryza sativa L.)

The extensive use of antibiotics worldwide has led to phytotoxicity and high risks to humans. Although research on the physiological toxicity of antibiotics is extensive, its influence on plant nitrogen uptake and assimilation remains unclear. The effect of enrofloxacin on nitrogen transformation and assimilation in rice (Oryza sativa L.) seedlings was investigated in this study. Enrofloxacin had no significant effect on rice growth, nitrogen assimilation and metabolism at low concentration, while significant changes were observed in high concentration. The growth of rice seedlings was inhibited, nitrate uptake was enhanced and nitrogen content increased significantly in both shoots and roots in enrofloxacin (800 μg L^-1) treatment. Furthermore, enrofloxacin promoted the activity of enzymes related to nitrogen assimilation, including nitrate reductase, nitrite reductase, glutamine synthetase, glutamate synthase, and glutamate dehydrogenase. High enzyme activity resulted in an increase in intermediate products and protein content, suggesting that rice seedlings may detoxify enrofloxacin stress through amino acid binding and nitro-oxidative stress might be one of the reasons of phenotype change. Gas chromatography-mass spectrometry results revealed that different types of metabolites in both shoots and roots increased with enrofloxacin stress. Specifically, glycine, serine, and threonine metabolism; aminoacyl-tRNA biosynthesis; alanine, aspartate, and glutamate metabolism; butanoate metabolism; glyoxylate and dicarboxylate metabolism in shoot; and tyrosine metabolism and citrate cycle in root were affected. Moreover, a significant correlation between nitrogen content, nitrogen assimilation enzyme activity, and metabolite content was observed. Collectively, these findings reveal the potential risks of using reclaimed wastewater irrigation and/or antibiotic-containing animal fertilizers on crops.

Integrated multi-biomarker responses of juvenile rainbow trout (Oncorhynchus mykiss) to an environmentally relevant pharmaceutical mixture

Pharmaceuticals are emerging pollutants of concern for aquatic ecosystems where they are occurring in complex mixtures. In the present study, the chronic toxicity of an environmentally relevant pharmaceutical mixture on juvenile rainbow trout (Oncorhynchus mykiss) was investigated. Five pharmaceuticals (paracetamol, carbamazepine, diclofenac, naproxen and irbesartan) were selected based on their detection frequency and concentration levels in the Meuse river (Belgium). Fish were exposed for 42 days to three different concentrations of the mixture, the median one detected in the Meuse river, 10-times and 100-times this concentration. Effects on the nervous, immune, antioxidant, and detoxification systems were evaluated throughout the exposure period and their response standardized using the Integrated Biomarker Response (IBRv2) index. IBRv2 scores increased over time in the fish exposed to the highest concentration. After 42 days, fish exposed to the highest concentration displayed significantly higher levels in lysozyme activity (p < 0.01). The mixture also caused significant changes in brain serotonin turnover (p < 0.05). In short, our results indicate that the subchronic waterborne exposure to a pharmaceutical mixture commonly occurring in freshwater ecosystems may affect the neuroendocrine and immune systems of juvenile rainbow trout.

A critical review on environmental presence of pharmaceutical drugs tested for the covid-19 treatment

On March 11, 2020, the World Health Organization (WHO) declared COVID-19 a pandemic. The outbreak caused a worldwide impact, becoming a health threat to the general population and its professionals. To date, there are no specific antiviral treatments or vaccines for the COVID-19 infection, however, some drugs are being clinically tested. The use of these drugs on large scale raises great concern about their imminent environmental risk, since the elimination of these compounds by feces and urine associated with the inefficiency of sewage treatment plants in their removal can result in their persistence in the environment, putting in risk the health of humans and of other species. Thus, the goal of this work was to conduct a review of other studies that evaluated the presence of the drugs chloroquine, hydroxychloroquine, azithromycin, ivermectin, dexamethasone, remdesivir, favipiravir and some HIV antivirals in the environment. The research indicated the presence of these drugs in the environment in different regions, with concentration data that could serve as a basis for further comparative studies following the pandemic.