Persistence, environmental hazards, and mitigation of pharmaceutically active residual contaminants from water matrices

Identifying pathways of pharmaceutical exposure in a mesoconsumer marine fish

Pharmaceutical uptake involves processes that vary across aquatic systems and biota. However, single studies examining multiple environmental compartments, microhabitats, biota, and exposure pathways in mesoconsumer fish are sparse. We investigated the pharmaceutical burden in bonefish (Albula vulpes), pathways of exposure, and estimated exposure to a human daily dose. To evaluate exposure pathways, the number and composition of pharmaceuticals across compartments and the bioconcentration in prey and bonefish were assessed. To evaluate bioaccumulation, we proposed the use of a field-derived bioaccumulation factor (fBAF), due to variability inherent to natural systems. Exposure to a human daily dose was based on bonefish daily energetic requirements and consumption rates using pharmaceutical concentrations in prey. Pharmaceutical number and concentration were highest in prey, followed by bonefish, water and sediment. Fifteen pharmaceuticals were detected in common among bonefish, prey, and water; all of which bioconcentrated in prey and bonefish, and four bioaccumulated in bonefish. The composition of detected pharmaceuticals was compartment specific, and prey were most similar to bonefish. Bonefish were exposed to a maximum of 1.2 % of a human daily dose via prey consumption. Results highlight the need for multicompartment assessments of exposure and consideration of prey along with water as a pathway of exposure.

A Cross-Sectional Study to Assess the Knowledge of Pharmacy Students About Drug Pollution in Spain

The presence of pharmaceuticals in the environment is an issue of growing concern. The European Commission adopted the "European Union Strategic Approach to Pharmaceuticals in the Environment", which focuses on actions to reduce the risk of pharmaceuticals in the environment, including how environmental aspects can become part of medical training programs.

OBJECTIVE

Obtain data from pharmacy students about pharmaceutical pollution to provide information about the training needs that may help develop new actions related to the training and dissemination of this issue.

METHODS

A total of 1614 pharmacy students from 5 Schools of Pharmacy in Spain completed a self-administered questionnaire consisting of 24 questions: 13 about knowledge, 8 related to attitude, and 3 to opinion.

RESULTS

Around 75% of students reported that they did not know "One Health" or "emerging pollutant" concepts and around 88% declared that they did not know that diclofenac caused a catastrophic vulture decline in Asia. The importance of this topic and their attitude to acquiring new knowledge was evaluated higher than 8 points out of 10, while received training during their studies was a score of 2.8 points out of 10.

CONCLUSION

The knowledge about key concepts was relatively poor. In fact, they judged training about pharmaceuticals in the environment during their pharmacy studies was very scarce. However, students consider drug pollution to be a very important issue and have a very good attitude toward acquiring knowledge about it.

Functional Bio-Based Polymeric Hydrogels for Wastewater Treatment: From Remediation to Sensing Applications

In recent years, many researchers have focused on designing hydrogels with specific functional groups that exhibit high affinity for various contaminants, such as heavy metals, organic pollutants, pathogens, or nutrients, or environmental parameters. Novel approaches, including cross-linking strategies and the use of nanomaterials, have been employed to enhance the structural integrity and performance of the desired hydrogels. The evolution of these hydrogels is further highlighted, with an emphasis on fine-tuning features, including water absorption capacity, environmental pollutant/factor sensing and selectivity, and recyclability. Furthermore, this review investigates the emerging topic of stimuli-responsive smart hydrogels, underscoring their potential in both sorption and detection of water pollutants. By critically assessing a wide range of studies, this review not only synthesizes existing knowledge, but also identifies advantages and limitations, and describes future research directions in the field of chemically engineered hydrogels for water purification and monitoring with a low environmental impact as an important resource for chemists and multidisciplinary researchers, leading to improvements in sustainable water management technology.

Comparative study of emerging pollutants of interest in the groundwater of the volcanic islands of La Palma and El Hierro (Canary Islands)

Emerging pollutants (EPs) include a wide array of chemical compounds, as well as some microorganisms, which presence was unknown or unmeasurable until recently, or have recently started to be considered a threat towards the environment or animal and human health. No clear or homogeneous regulations exist for their measurement or control, and efforts should be made to assess their presence and offer solutions for their safe management, as well as to achieve an optimal protection of water resources. A previous study performed by our research group thoroughly studied a wide profile of EPs in El Hierro Island (Canary Islands) for the first time. Now, we present the study of the same panel of 70 EPs in La Palma Island (Canary Islands). 14 samples were collected in 2021, at different locations in La Palma island, representing seven municipalities (Los Llanos de Aridane, Santa Cruz de la Palma, El Paso, Breña Baja, Tazacorte, Barlovento and Fuencaliente) and four installation types (Piezometers/Wells, Wastewater Treatment Plant (WWTP), Water Gallery and Water Springs). High performance liquid chromatography-mass spectrometry (HPLC-MS) was performed to analyse the EP array, which included five chemical families: UV filters, UV blockers/stabilizers, parabens, Pharmaceutical Active Compounds (PhACs) and pesticides. Subsequently, a comprehensive descriptive and statistical analysis, including different tests was performed on the data obtained. Heterogeneous concentration levels of the EPs studied were found based on municipality and installation type among the island, with some of the PhACs and UV blockers/stabilizers showing very high levels, especially at Breña Baja and wastewater treatment plants (WWTPs). It is worth noting that some of the samples comprised within the WWTPs category were collected outside the treatment plant, after water has been treated, so they should not bear dangerous concentrations of any hazardous compound. The high presence of two pesticides, imidacloprid (ranging from 68.7 to 24,896.5 ng⋅L-1) and acetamiprid (ranging from 1010.7 to 5168.1 ng⋅L-1) was worth highlighting too. In addition, three EP concentration clusters were found to virtually divide the island based on mathematical percentiles of EP mean concentrations, which can help gain more insight into the contamination status of the island and measures that could be taken for their management. Finally, a comparison between La Palma results and the profile observed at El Hierro by our research group was presented. Altogether, the study performed calls for a need to take actions towards avoiding entrance of EPs in the water cycle, and not just focusing on remediation strategies once they have reached the groundwater, freshwater or soil.

Developing an Approach for Integrating Chemical Analysis and Transcriptional Changes to Assess Contaminants in Water, Sediment, and Fish

Pharmaceuticals in aquatic environments pose threats to aquatic organisms because of their continuous release and potential accumulation. Monitoring methods for these contaminants are inadequate, with targeted analyses falling short in assessing water quality's impact on biota. The present study advocates for integrated strategies combining suspect and targeted chemical analyses with molecular biomarker approaches to better understand the risks posed by complex chemical mixtures to nontarget organisms. The research aimed to integrate chemical analysis and transcriptome changes in fathead minnows to prioritize contaminants, assess their effects, and apply this strategy in Wascana Creek, Canada. Analysis revealed higher pharmaceutical concentrations downstream of a wastewater-treatment plant, with clozapine being the most abundant in fathead minnows, showing notable bioavailability from water and sediment sources. Considering the importance of bioaccumulation factor and biota-sediment accumulation factor in risk assessment, these coefficients were calculated based on field data collected during spring, summer, and fall seasons in 2021. Bioaccumulation was classified as very bioaccumulative with values >5000 L kg-1, suggesting the ability of pharmaceuticals to accumulate in aquatic organisms. The study highlighted the intricate relationship between nutrient availability, water quality, and key pathways affected by pharmaceuticals, personal care products, and rubber components. Prioritization of these chemicals was done through suspect analysis, supported by identifying perturbed pathways (specifically signaling and cellular processes) using transcriptomic analysis in exposed fish. This strategy not only aids in environmental risk assessment but also serves as a practical model for other watersheds, streamlining risk-assessment processes to identify environmental hazards and work toward reducing risks from contaminants of emerging concern. Environ Toxicol Chem 2024;00:1-22. © 2024 SETAC.

Use of sawdust for production of ligninolytic enzymes by white-rot fungi and pharmaceutical removal

Use of white-rot fungi for enzyme-based bioremediation of wastewater is of high interest. These fungi produce considerable amounts of extracellular ligninolytic enzymes during solid-state fermentation on lignocellulosic materials such as straw and sawdust. We used pure sawdust colonized by Pleurotus ostreatus, Trametes versicolor, and Ganoderma lucidum for extraction of ligninolytic enzymes in aqueous suspension. Crude enzyme suspensions of the three fungi, with laccase activity range 12-43 U/L and manganese peroxidase activity range 5-55 U/L, were evaluated for degradation of 11 selected pharmaceuticals spiked at environmentally relevant concentrations. Sulfamethoxazole was removed significantly in all treatments. The crude enzyme suspension from P. ostreatus achieved degradation of wider range of pharmaceuticals when the enzyme activity was increased. Brief homogenization of the colonized sawdust was also observed to be favorable, resulting in significant reductions after a short exposure of 5 min. The highest reduction was observed for sulfamethoxazole which was reduced by 84% compared to an autoclaved control without enzyme activity and for trimethoprim which was reduced by 60%. The compounds metoprolol, lidocaine, and venlafaxine were reduced by approximately 30% compared to the control. Overall, this study confirmed the potential of low-cost lignocellulosic material as a substrate for production of enzymes from white-rot fungi. However, monitoring over time in bioreactors revealed a rapid decrease in enzymatic ligninolytic activity.

Monitoring Pharmaceuticals and Personal Care Products in Healthcare Effluent Wastewater Samples and the Effectiveness of Drug Removal in Wastewater Treatment Plants Using the UHPLC-MS/MS Method

A multi-residue UHPLC-MS/MS analytical method, previously developed for monitoring 52 pharmaceuticals in drinking water, was used to analyse these pharmaceuticals in wastewater originating from healthcare facilities in the Czech Republic. Furthermore, the methodology was expanded to include the evaluation of the effectiveness of drug removal in Czech wastewater treatment plants (WWTPs). Of the 18 wastewater samples analysed by the validated UHPLC-MS/MS, each sample contained at least one quantifiable analyte. This study reveals the prevalence of several different drugs; mean concentrations of 702 μg L-1 of iomeprol, 48.8 μg L-1 of iopromide, 29.9 μg L-1 of gabapentin, 42.0 μg L-1 of caffeine and 82.5 μg L-1 of paracetamol were present. An analysis of 20 samples from ten WWTPs revealed different removal efficiencies for different analytes. Paracetamol was present in the inflow samples of all ten WWTPs and its removal efficiency was 100%. Analytes such as caffeine, ketoprofen, naproxen or atenolol showed high removal efficiencies exceeding 80%. On the other hand, pharmaceuticals like furosemide, metoprolol, iomeprol, zolpidem and tramadol showed lower removal efficiencies. Four pharmaceuticals exhibited higher concentrations in WWTP effluents than in the influents, resulting in negative removal efficiencies: warfarin at -9.5%, indomethacin at -53%, trimethoprim at -54% and metronidazole at -110%. These comprehensive findings contribute valuable insights to the pharmaceutical landscape of wastewater from healthcare facilities and the varied removal efficiencies of Czech WWTPs, which together with the already published literature, gives a more complete picture of the burden on the aquatic environment.

Contaminants of emerging concern: Occurrence, analytical techniques, and removal with electrochemical advanced oxidation processes with special emphasis in Latin America

The occurrence of contaminants of emerging concern (CECs) in environmental systems is gradually more studied worldwide. However, in Latin America, the presence of contaminants of emerging concern, together with their environmental and toxicological impacts, has recently been gaining wide interest in the scientific community. This paper presents a critical review about the source, fate, and occurrence of distinct emerging contaminants reported during the last two decades in various countries of Latin America. In recent years, Brazil, Chile, and Colombia are the main countries that have conducted research on the presence of these pollutants in biological and aquatic compartments. Data gathered indicated that pharmaceuticals, pesticides, and personal care products are the most assessed CECs in Latin America, being the most common compounds the followings: atrazine, acenaphthene, caffeine, carbamazepine, ciprofloxacin, diclofenac, diuron, estrone, losartan, sulfamethoxazole, and trimethoprim. Most common analytical methodologies for identifying these compounds were HPLC and GC coupled with mass spectrometry with the potential to characterize and quantify complex substances in the environment at low concentrations. Most CECs' monitoring and detection were observed near to urban areas which confirm the out-of-date wastewater treatment plants and sanitization infrastructures limiting the removal of these pollutants. Therefore, the implementation of tertiary treatment should be required. In this tenor, this review also summarizes some studies of CECs removal using electrochemical advanced oxidation processes that showed satisfactory performance. Finally, challenges, recommendations, and future perspectives are discussed.

Next-generation hybrid technologies for the treatment of pharmaceutical industry effluents

Water and industries are intangible units of the globe that are always set to meet the population's demand. The global population depends on one-third of freshwater increasing the demand. The increase in population along with urbanization has polluted the fresh water resources. The pharmaceutical industry is marked as an emerging contaminant of water pollution. The most common type of pharmaceutical drugs that are detected in the environment includes antibiotics, analgesics, NSAIDs, and pain-relieving drugs. These drugs alter the food chain of the organisms causing chaos mainly in the marine ecosystem. Pharmaceutical drugs are found only in shallow amounts (ng/mg) they have a huge impact on the living system. The consumption of water contaminated with pharmaceutical ingredients can disrupt reproduction, hormonal imbalance, cancer, and respiratory problems. Various methods are used to remove these chemicals from the environment. In this review, we mainly focused on the emerging hybrid technologies and their significance in the effective treatment of pharmaceutical wastewater. This review paper primarily elaborates on the merits and demerits of existing conventional technologies helpful in developing integrated technologies for the modern era of pharmaceutical effluent treatment. This review paper further in detail discusses the various strategies of eco-friendly bioremediation techniques namely biostimulation, bioaugmentation, bacterial degradation, mycoremediation, phytoremediation, and others for the ultimate removal of pharmaceutical contaminants in wastewater. The review makes clear that targeted and hybrid solutions are what the world will require in the future to get rid of these pharmacological prints.

Photodegradation of anthelmintic drugs under natural sunlight and simulated irradiation: kinetics, mechanisms, transformation products, and toxicity

Albendazole (ALB) and bithionol (BIT) are two anthelmintic drugs (ADs) with high consumption from benzimidazole group and diphenylsulfide group, respectively. However, information on the transformation of the two anthelmintics under environmental condition is scare. Therefore, in the present study, we investigated the natural attenuation of the two ADs in the aquatic environment, including biodegradation, hydrolysis, and direct and indirect photodegradation. The direct photodegradation occupied a vast portion among other degradation pathways of the two ADs in natural water, with near-surface summer half-lives of 0.272-0.387 h and 0.110-0.520 h for ALB and BIT, respectively. Suspended particles in water were found to facilitate the photodegradation of the two ADs. Study on the indirect photodegradation demonstrated the positive roles of singlet oxygen (1O2) and excited triplet dissolved organic matter (3DOM*) in the photolysis of the two ADs, whereas the hydroxyl radical (•OH) affected little on the overall photodegradation procedures of ALB due to the scavenging effect of HCO3-. Dual effects of DO, DOM, HCO3-, NO3-, and NO2- on the photodegradation of ALB and BIT were perceived. Transformation intermediates (TIs) of the two ADs during photodegradation were analyzed by UHPLC-QTOF-MS. Six TIs of ALB were identified, including a broad-spectrum fungicide carbendazim and another common AD ricobendazole. Two TIs of BIT yielded from dechlorination were also detected. Probable transformation mechanism and predicted aquatic ecotoxicity based on the identified TIs were unveiled.

Occurrence, spatial and seasonal variations of emerging contaminants in the aquatic environment of Sharjah, United Arab Emirates

The occurrence, seasonal variations and spatial distribution of emerging contaminants (ECs) in wastewater effluents from wastewater treatment plant (WWTP) and UAE's receiving coastal aquatic environment (seawater and sediments) were evaluated in the present study. A total of 21, 23, and 22 contaminants in the effluents, seawater, and sediments, respectively, at concentrations ranging from low ng L-1 up to 1782 ng L-1 in effluents, from low ng/l up to 236.10 ng L-1 in seawater, and from low ng g-1 up to 60.15 ng g-1 in sediments were recorded. The study revealed that imidacloprid, thiabendazole, and acetaminophen were the most ubiquitous compounds in effluents, seawater, and sediments, respectively, since they were found in all samples collected with a detection frequency of 100%. The study also revealed that the higher concentrations of most contaminants were recorded in autumn. However, thiabendazole in effluents and seawater, acetamiprid in effluents, and sulphapyridine in seawater and sediments showed a higher load in winter. This study highlights the need for proper monitoring and management of ECs in wastewater effluents, seawater, and sediments, especially during the autumn and winter seasons, to minimize their impact on the marine ecosystem and public health.

Modified polymer membranes for the removal of pharmaceutical active compounds in wastewater and its mechanism-A review

Membrane technology can play a suitable role in removing pharmaceutical active compounds since it requires low energy and simple operation. Even though membrane technology has progressed for wastewater applications nowadays, modifying membranes to achieve the strong desired membrane performance is still needed. Thus, this study overviews a comprehensive insight into the application of modified polymer membranes to remove pharmaceutical active compounds from wastewater. Biotoxicity of pharmaceutical active compounds is first prescribed to gain deep insight into how membranes can remove pharmaceutical active compounds from wastewater. Then, the behavior of the diffusion mechanism can be concisely determined using mass transfer factor model that represented by β and B with value up to 2.004 g h mg-1 and 1.833 mg g-1 for organic compounds including pharmaceutical active compounds. The model refers to the adsorption of solute to attach onto acceptor sites of the membrane surface, external mass transport of solute materials from the bulk liquid to the membrane surface, and internal mass transfer to diffuse a solute toward acceptor sites of the membrane surface with evidenced up to 0.999. Different pharmaceutical compounds have different solubility and relates to the membrane hydrophilicity properties and mechanisms. Ultimately, challenges and future recommendations have been presented to view the future need to enhance membrane performance regarding fouling mitigation and recovering compounds. Afterwards, the discussion of this study is projected to play a critical role in advance of better-quality membrane technologies for removing pharmaceutical active compounds from wastewater in an eco-friendly strategy and without damaging the ecosystem.

Quantification of pharmaceuticals in hospital effluent: Weighted ranking of environmental risk using a fuzzy hybrid multicriteria method

An analytical method for quantification of seventeen pharmaceuticals and one metabolite was validated and applied in the analysis of hospital effluent samples. Two different sampling strategies were used: seasonal sampling, with 7 samples collected bimonthly; and hourly sampling, with 12 samples collected during 12 h. Thus, the variability was both seasonal and within the same day. High variability was observed in the measured concentrations of the pharmaceuticals and the metabolite. The quantification method, performed using weighted linear regression model, demonstrated results of average concentrations in seasonal samples ranged between 0.19 μgL-1 (carbamazepine) and higher than 61.56 μgL-1 (acetaminophen), while the hourly samples showed average concentrations between 0.07 μgL-1 (diazepam) and higher than 54.91 μgL-1 (acetaminophen). It is described as higher because the maximum concentration of the calibration curve took into account the dilution factor provided by DLLME. The diurnal results showed a trend towards higher concentrations in the first and last hours of sampling. The risk quotient (RQ) was calculated using organisms from three different trophic levels, for all the analytes quantified in the samples. Additionally, in order to understand the level of importance of each RQ, an expert panel was established, with contributions from 23 specialists in the area. The results were analyzed using a hybrid decision-making approach based on a Fuzzy Analytic Hierarchy Process (FAHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, in order to rank the compounds by environmental risk priority. The compounds of greatest concern were losartan, acetaminophen, 4-aminoantipyrine, sulfamethoxazole, and metoclopramide. Comparison of the environmental risk priority ranking with the potential human health risk was performed by applying the same multicriteria approach, with the prediction of endpoints using in silico (Q)SAR models. The results obtained suggested that sulfamethoxazole and acetaminophen were the most important analytes to be considered for monitoring.

The microbial removal of bisphenols in aquatic microcosms and associated alteration in bacterial community

The concept of the study resulted from numerous concerns around bisphenol A (BPA) and bisphenol S (BPS) in aquatic environments. In this study, river water and sediment microcosms highly polluted with bisphenols and bioaugmented with two BPs-removing bacterial strains were constructed. The study aimed to determine the rate of high-concentrated BPA and BPS (BPs) removal from river water and sediment microniches, and the effect of water bioaugmentation with bacterial consortium on the removal rates of these pollutants. Moreover, the impact of introduced strains and exposure to BPs on the structural and functional composition of the autochthonous bacterial communities was elucidated. Our findings indicate that the removal activity of autochthonous bacteria was sufficient for effectively BPA elimination and reducing BPS content in the microcosms. The number of introduced bacterial cells decreased continuously until day 40, and on consecutive sampling days, no bioaugmented cells were detected. Sequencing analysis of the total 16S rRNA genes revealed that the community composition in bioaugmented microcosms amended with BPs differed significantly from those treated either with bacteria or BPs. A metagenomic analysis found an increase in the abundance of proteins responsible for xenobiotics removal in BPs-amended microcosms. This study provides new insights into the effects of bioaugmentation with a bacterial consortium on bacterial diversity and BPs removal in aquatic environments.

The potential of fungi in the bioremediation of pharmaceutically active compounds: a comprehensive review

The ability of fungal species to produce a wide range of enzymes and metabolites, which act synergistically, makes them valuable tools in bioremediation, especially in the removal of pharmaceutically active compounds (PhACs) from contaminated environments. PhACs are compounds that have been specifically designed to treat or alter animal physiological conditions and they include antibiotics, analgesics, hormones, and steroids. Their detrimental effects on all life forms have become a source of public outcry due their persistent nature and their uncontrolled discharge into various wastewater effluents, hospital effluents, and surface waters. Studies have however shown that fungi have the necessary metabolic machinery to degrade PhACs in complex environments, such as soil and water, in addition they can be utilized in bioreactor systems to remove PhACs. In this regard, this review highlights fungal species with immense potential in the biodegradation of PhACs, their enzymatic arsenal as well as the probable mechanism of biodegradation. The challenges encumbering the real-time application of this promising bioremediative approach are also highlighted, as well as the areas of improvement and future perspective. In all, this paper points researchers to the fact that fungal bioremediation is a promising strategy for addressing the growing issue of pharmaceutical contamination in the environment and can help to mitigate the negative impacts on ecosystems and human health.

First emerging pollutants profile in groundwater of the volcanic active island of El Hierro (Canary Islands)

Emerging pollutants (EPs) are substances present in wastewater that have not been studied, previously, leading to ambiguity in regulations for their presence in water resources. Territories that are highly dependent on groundwater resources are at a high risk of suffering the consequences of EP contamination due to their dependence on good quality groundwater for agriculture, drinking, and other uses. A relevant example is El Hierro (Canary Islands), which was declared a biosphere reserve by the UNESCO in 2000 and is almost completely powered by renewable energies. Using high performance liquid chromatography-mass spectrometry, the concentrations of 70 EPs were assessed at 19 sampling points on El Hierro. The results indicated that no pesticides were present in groundwater; however, varied concentration levels of ultraviolet (UV) filters, UV stabilizers/blockers and pharmaceutically active compounds (PhACs) were found, with La Frontera being the most contaminated municipality. With regard to the different installation types, piezometers and wells were the ones showing the highest concentrations for most EPs. Interestingly, the depth of sampling correlated positively with EP concentration, and four different clusters virtually dividing the island into two areas could be identified based on the presence of each EP. More studies should be performed to ascertain why a few of the EPs showed considerably high concentrations at different depths. The results obtained highlight the need to, not only implement remediation measures once EPs have reached the soil and aquifers, but also to avoid their incorporation into the water cycle via homes, animal husbandry, agriculture, industry, and wastewater treatment plants (WWTPs).

Quantum and experimental investigation of the application of Crassostrea gasar (mangrove oyster) shell-based CaO nanoparticles as adsorbent and photocatalyst for the removal of procaine penicillin from aqueous solution

The present study was designed to synthesize and characterize calcium oxide nanoparticles (using mangrove oyster shell as a precursor) and apply the synthesized nanoparticles as a photocatalyst to degrade procaine penicillin in an aqueous solution. The photocatalyst exhibited an average band gap of 4.42 eV, showed a maximum wavelength of absorbance in the UV region (i.e., 280 nm), and is a microporous nanoparticle with a particle diameter of 50 nm. The photocatalyzed degradation of the drug was conducted under natural sunlight, and the influence of parameters such as the period of contact, catalyst load, pH, initial drug concentration, and ionic strength was investigated concerning the degradation profile. The results obtained from response surface analysis indicated that an optimum degradation efficiency of about 93% can be obtained at a concentration, pH, and catalyst dosage of 0.125 M, 2, and 0.20 g respectively, at 0.902 desirabilities. The Langmuir-Hinshelwood, modified Freundlich, parabolic diffusion, pseudo-first-/second-order, and zero-, first-, and second-order kinetic parameters were tested to ascertain the best model that best described the experimental data. Consequently, the Langmuir-Hinshelwood, modified Freundlich, and pseudo-second-order models were accepted based on the minimum error and higher R² values. Based on the Langmuir-Hinshelwood rate constants for adsorption and photodegradation as well as the evaluated valence bond potential, the degradation of the drug first proceeded through the mechanism of adsorption and followed by the oxidation of the drug by superoxide (generated from the interaction of electrons that generated by through the absorption of UV radiation). The quantum chemical calculation gave evidence that pointed towards the establishment of strong agreement with experimental data and also showed that the carboxyl functional group in the drug is the target site for adsorption and subsequent degradation.

Unravelling joint cytotoxicity of ibuprofen and oxytetracycline on Chlamydomonas reinhardtii using a programmed cell death-related biomarkers panel

Pharmaceutical active compounds (PhACs) are emerging contaminants that pose a growing concern due to their ubiquitous presence and harmful impact on aquatic ecosystems. Among PhACs, the anti-inflammatory ibuprofen (IBU) and the antibiotic oxytetracycline (OTC) are two of the most used compounds whose presence has been reported in different aquatic environments worldwide. However, there is still scarce information about the cellular and molecular alterations provoked by IBU and OTC on aquatic photosynthetic microorganisms as microalgae, even more if we refer to their potential combined toxicity. To test the cyto- and genotoxicity provoked by IBU, OTC and their binary combination on Chlamydomonas reinhardtii, a flow cytometric panel was performed after 24 h of single and co-exposure to both contaminants. Assayed parameters were cell vitality, metabolic activity, intracellular ROS levels, and other programmed cell death (PCD)-related biomarkers as cytoplasmic and mitochondrial membrane potentials and caspase-like and endonuclease activities. In addition, a nuclear DNA fragmentation analysis by comet assay was carried out. For most of the parameters analysed (vitality, metabolic activity, cytoplasmic and mitochondrial membrane potentials, and DNA fragmentation) the most severe damages were observed in the cultures exposed to the binary mixture (IBU+OTC), showing a joint cyto- and genotoxicity effect. Both PhACs and their mixture caused a remarkable decrease in cell proliferation and metabolic activity and markedly increased intracellular ROS levels, parallel to a noticeable depolarization of cytoplasmic and mitochondrial membranes. Moreover, a strong increase in both caspase and endonuclease activities as well as a PCD-related loss of nuclear DNA integrity was observed in all treatments. Results analysis showed that the PhACs caused cell death on this non-target organism, involving mitochondrial membrane depolarization, enhanced ROS production and activation of PCD process. Thus, PCD should be an applicable toxicological target for unraveling the harmful effects of co-exposure to PhACs in aquatic organisms as microalgae.

Eco-friendly bioremediation of pollutants from contaminated sewage wastewater using special reference bacterial strain of Bacillus cereus SDN1 and their genotoxicological assessment in Allium cepa

The present study aimed to assess the Bacillus cereus SDN1 native bacterium's ability to clean up contaminated or polluted water. The isolated bacterium was identified by its morphological and biochemical characteristics, which were then confirmed at the genus level. Furthermore, the isolated B. cereus (NCBI accession No: MW828583) was identified genomically by PCR amplifying 16 s rDNA using a universal primer. The phylogenetic analysis of the rDNA sequence was analyzed to determine the taxonomic and evolutionary profile of the isolate of the previously identified Bacillus sp. Besides, B. cereus and the bacterial consortium were treated using sewage wastewater. After 15 days of treatment, the following pollutants or chemicals were reduced: total hardness particles removal varied from 63.33 % to 67.55 %, calcium removal varied from 90 % to 93.33 %, and total nitrate decreased range from 37.77 % to 22.22 %, respectively. Electrical conductivity ranged from 1809 mS/cm to 2500 mS/cm, and pH values ranged from 6.5 to 8.95. The outcome of in-situ remediation results suggested that B. cereus has a noticeable remediation efficiency to the suspended particles. A root tip test was also used to investigate the genotoxicity of treated and untreated sewage-contaminated waters on onion (Allium cepa) root cells. The highest chromosomal aberrations and mitotic inhibition were found in roots exposed to contaminated sewage water, and their results displayed chromosome abnormalities, including disorganized, sticky chain, disturbed metaphase, chromosomal displacement in anaphase, abnormal telophase, spindle disturbances, and binucleate cells observed in A. cepa exposed to untreated contaminated water. The study can thus be applied as a biomarker to detect the genotoxic impacts of sewage water pollution on biota. Furthermore, based on an identified bacterial consortium, this work offers a low-cost and eco-favorable method for treating household effluents.

Environmentally Benign Nanoparticles for the Photocatalytic Degradation of Pharmaceutical Drugs

A rapid rise in industrialization has led to the release of pharmaceutical pollutants into water bodies, rendering water inappropriate for consumption by humans and animals, challenging our efforts to achieve the clean water sustainable development goal. These pharmaceutical pollutants include antibiotics, anticancer drugs, antidepressants, etc., which are highly stable and persistent in water, in addition to being harmful to life. At times, the secondary pollutant that is formed after degradation is more potent than the parent drug. Conventional water purification methods cannot completely remove these pollutants. Hence, efficient and robust methods are required to degrade pharmaceutical waste. Photocatalytic degradation of drugs is deemed an efficient and effective method for environmental remediation, along with recovery of photocatalysts, which are important for recycling and sustainable use. Herein, we present the synthesis of nanoparticles (NPs) and their application for photocatalytic degradation of pharmaceutical waste as a preferred water treatment method. Additionally, green synthesis of photocatalytic nanomaterials offers the benefit of avoiding secondary pollution. The green synthesis of NPs is employed by using plant extracts that offer a number of metabolites as reducing agents or capping agents, as well as the use of microbes as green nanofactories to tackle the issue of water cleanliness with respect to pharmaceutical waste. Despite regulations concerning drug disposal, some underdeveloped countries do not enforce and practice these guidelines in letter and spirit. Hence, the current work presenting a promising water cleanliness method is expected to contribute to the assurance of strict policy compliance and enforcement, resulting in the resolution of the health concerns with respect to hazardous pharmaceutical waste disposal in water bodies.

Development of Regular Hydrophobic Silica Aerogel Microspheres for Efficient Oil Adsorption

The objective of this research was to develop new hydrophobic silica aerogel microspheres (HSAMs) with water glass and hexmethyldisilazane for oil adsorption. The effects of the hexmethyldisilazane concentration and drying method on the structure and organic liquid adsorption capacity were investigated. The hexmethyldisilazane concentration of the modification solution did not influence the microstructure and pore structure in a noteworthy manner, which depended more on the drying method. Vacuum drying led to more volume shrinkage of the silica gel microsphere (SGM) than supercritical CO₂ drying, thus resulting in a larger apparent density, lower pore volume, narrower pore size distribution, and more compact network. Owing to the large pore volume and pore size, the HSAMs synthesized via supercritical CO₂ drying had a larger organic liquid adsorption capacity. The adsorption capacities of the HSAMs with pore volumes of 4.04-6.44 cm³/g for colza oil, vacuum pump oil, and hexane are up to 18.3, 18.9, and 11.8 g/g, respectively, higher than for their state-of-the-art counterparts. The new sorbent preparation method is facile, cost-effective, safe, and ecofriendly, and the resulting HSAMs are exceptional in capacity, stability, and regenerability.

Stereospecific Self-Assembly Processes of Porphyrin-Proline Conjugates: From the Effect of Structural Features and Bulk Solvent Properties to the Application in Stereoselective Sensor Systems

Conjugating the porphyrin ring with an amino acid via amide linkage represents a straightforward way for conferring both amphiphilicity and chirality to the macrocycle. Proline residue is a good choice in this context since its conformational rigidity allows for porphyrin assembling where molecular chirality is efficiently transferred and amplified using properly honed aqueous environments. Herein, we describe the evolution of the studies carried out by our group to achieve chiral systems from some porphyrin-proline derivatives, both in solution and in the solid state. The discussion focuses on some fundamental aspects reflecting on the final molecular architectures obtained, which are related to the nature of the appended group (stereochemistry and charge), the presence of a metal ion coordinated to the porphyrin core and the bulk solvent properties. Indeed, fine-tuning the mentioned parameters enables the achievement of stereospecific structures with distinctive chiroptical and morphological features. Solid films based on these chiral systems were also obtained and their recognition abilities in gaseous and liquid phase are here described.

Bio-removal of emerging pollutants by advanced bioremediation techniques

This review highlights the relevance of bioremediation techniques for the removal of emerging pollutants (EPs). The EPs are chemical or biological pollutants that are not currently monitored or regulated by environmental authorities, but which can enter the environment and cause harmful effects to the environment and human health. In recent times, an ample range of EPs have been found in water bodies, where they can unbalance ecosystems and cause negative effects on non-target species. In addition, some EPs have shown high rates of bioaccumulation in aquatic species, thus affecting the safety and quality of seafood. The negative impacts of emerging pollutants, their wide distribution in the environment, their bioaccumulation rates, and their resistance to wastewater treatment plants processes have led to research on sustainable remediation. Remediation techniques have been recently directed to advanced biological remediation technologies. Such technologies have exhibited numerous advantages like in-situ remediation, low costs, eco-friendliness, high public acceptance, and so on. Thus, the present review has compiled the most recent studies on bioremediation techniques for water decontamination from emerging pollutants to extend the current knowledge on sustainable remediation technologies. Biological emerging contaminants, agrochemicals, endocrine-disrupting chemicals, and pharmaceutical and personal care products were considered for this review study, and their removal by bioremediation techniques involving plants, bacteria, microalgae, and fungi. Finally, further research opportunities are presented based on current challenges from an economic, biological, and operation perspective.

Carbon-based nanocomposite materials with multifunctional attributes for environmental remediation of emerging pollutants

Carbon-based materials are among the most biosynthesized nanocomposites with excellent tunability and multifunctionality features, that other materials fail to demonstrate. Naturally occurring materials, such as alginate (Alg), can be combined and modified by linking the active moieties of various carbon-based materials of interest, such as graphene oxide (GO), carbon nanotubes (CNTs), and mesoporous silica nanocomposite (MSN), among others. Thus, several types of robust nanocomposites have been fabricated and deployed for environmental remediation of emerging pollutants, such as pharmaceutical compounds, toxic dyes, and other environmentally hazardous contaminants of emerging concern. Considering the above critiques and added features of carbon-based nanocomposites, herein, an effort has been made to spotlight the synergies of GO, CNTs, and MSN with Alg and their role in mitigating emerging pollutants. From the information presented in this work, it can be concluded that Alg is a material that has excellent potential. However, its use still requires further tests in different areas and other materials to carry out a holistic investigation that exploits its versatility for environmental remediation purposes.

A critical review on microbes-based treatment strategies for mitigation of toxic pollutants

Contamination of the environment through toxic pollutants poses a key risk to the environment due to irreversible environmental damage(s). Industrialization and urbanization produced harmful elements such as petrochemicals, agrochemicals, pharmaceuticals, nanomaterials, and herbicides that are intentionally or unintentionally released into the water system, threatening biodiversity, the health of animals, and humans. Heavy metals (HMs) in water, for example, can exist in a variety of forms that are inclined by climate features like the presence of various types of organic matter, pH, water system hardness, transformation, and bioavailability. Biological treatment is an important tool for removing toxic contaminants from the ecosystem, and it has piqued the concern of investigators over the centuries. In situ bioremediation such as biosparging, bioventing, biostimulation, bioaugmentation, and phytoremediation and ex-situ bioremediation includes composting, land farming, biopiles, and bioreactors. In the last few years, scientific understanding of microbial relations with particular chemicals has aided in the protection of the environment. Despite intensive studies being carried out on the mitigation of toxic pollutants, there have been limited efforts performed to discuss the solutions to tackle the limitations and approaches for the remediation of heavy metals holistically. This paper summarizes the risk assessment of HMs on aquatic creatures, the environment, humans, and animals. The content of this paper highlights the principles and limitations of microbial remediation to address the technological challenges. The coming prospect and tasks of evaluating the impact of different treatment skills for pollutant remediation have been reviewed in detail. Moreover, genetically engineered microbes have emerged as powerful bioremediation capabilities with significant potential for expelling toxic elements. With appropriate examples, current challenging issues and boundaries related to the deployment of genetically engineered microbes as bioremediation on polluted soils are emphasized.

A Strategy for Sample Preparation: Using Egg White Gel to Promote the Determination of Aflatoxin M1 Content in Milk Samples

The analysis of food samples is a challenging task. The high complexity of food matrices hinders the extraction and detection of analytes from them. Therefore, the correct preparation of food samples is a crucial step for their subsequent analysis, as it achieves the proper isolation and preconcentration of analytes and removes the interfering proportion of the food matrix before instrumental analysis. We aimed to develop a method that not only satisfies the requirement of detecting trace compounds in complex matrices but also achieves a "greener" approach by reducing the use of organic solvents and non-degradable materials to minimize the health hazards posed to the operators as well as pollution to the environment. In this study, we prepared egg white as a concentrated gel and used this material for the biological purification of milk samples. After the milk protein was removed by acidification and salting, the residual amount of aflatoxin M1 in milk samples was quantitatively determined by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that the novel egg white purification method possessed advantages over the immunoaffinity technique used as the reference method in extraction recovery, sensitivity, repeatability, and operability. The limit of detection (LOD) was 0.001 μg/kg. In spiked samples containing 0.01 μg/kg to 2 μg/kg of AFM1, the average recovery was 88.3-94.7%, with a precision of 6.1-11.0%. Improved repeatability was obtained by significantly reducing the operation time and resource requirements compared with the immunoaffinity technique currently used internationally. This study provides a reference for the further improvement of the relevant international standards in place for the detection of aflatoxin M1 in milk.

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.

Ozonation and UV photolysis for removing anticancer drug residues from hospital wastewater

The present study investigates the use of UV light and the ozone process for doxorubicin, daunorubicin, epirubicin, and irinotecan degradation. The process was carried out using different pH values in hospital wastewater. The use of UV radiation reduces the concentration of anticancer drugs, but in all cases, this technology was not able enough to remove on the whole these contaminants from hospital wastewater. The best condition was achieved when using pH 9 for most of the analytes. Doxorubicin, daunorubicin, and epirubicin were degraded at 97.3%, 88.3%, and 99.0%, respectively. Irinotecan showed the lowest degradation, just 55.6%; a slightly higher degradation (63.8%) was obtained when pH 5 was used. Complete removal of doxorubicin, daunorubicin, epirubicin, and irinotecan was achieved when ozone treatment was used for all the pH studied. The results indicated that UV light and the ozone process can be used as a tertiary treatment to reduce the concentration of anticancer drugs in the effluents. Ozonation, therefore, proved to be more efficient than the photolysis process, when considering the percentual degradation of the original compounds in shorter timespans.