Search

Access to secure water sources has become one of the biggest challenges for human sustainability. Climate change and associated droughts make it difficult to guarantee the usual water source and move to groundwater use or to the re-use of treated wastewater remains unviable due the lack on the capacity of monitoring water quality. Moreover, reusing treated wastewater from repositories near anthropogenic sources represents a risk of high concentrations of emerging contaminants. The strategies involve a higher risk of encountering toxic elements with a heavy burden on human and environmental health. New accessible and reliable tools are required to detect any hazard from the waterbodies in real time to ensure safe management and also to decrease mismanagement or ilegal water discharges. One of the available options is to look into enzyme-based biosensors that can detect toxic elements in the water. The proposed biosensors require sensible elements to be accessible and durable for their proper function. The present revision shows in first place, the actual need of real time monitoring due the different sources and effects of emergent pollutants. Secondly, describes how enzymes can be immobilized for its application in biosensors and the rol enzymes play as bioreceptor element in biosensing. Thirdly, describes the transduction methods that can be observed, and finally the actual application of enzyme biosensors for the detection of different toxic elements. According to the presented literature enzyme-based biosensors have been successfully applied for the detection of a wide number of pollutants reaching detection limits comparable to traditional methods such as up to 0.018 nM of mercury. Furthermore, laccase seems to be the more applied enzyme in literature, but positive results are not limited to this enzyme and other candidates have been explored showing good detection rate. Graphical Abstract: [Figure not available: see fulltext.].

Wastewater-Based Epidemiology (WBE) has become a powerful tool in pandemics, serving as a surveillance strategy. However, there are numerous variables that affect the results obtained from wastewater, ultimately affecting the reliability of the information. These variables include dilution, temperature-related degradation, biomass growth, and other unexplored processes. Current models only consider temperature in their analysis. Furthermore, previous research is focused on few viruses. Hence, more complete models for viral RNA degradation on complex matrices are needed. Direct wastewater indicators identified and quantified by analytical chemistry from human consumption e.g., secondary metabolites from caffeine consumption, hormones, and molecular analysis of enteric viruses, previously unexplored, can be used as not only health indicators but also to help to determine the initial content of viral RNA. This review explores modeling tools, their challenges, and advances in the field of WBE.

The COVID-19 pandemic has brought increments in market sales and prescription of medicines commonly used to treat mental health disorders, such as depression, anxiety, stress, and related problems. The increasing use of these drugs, named psychiatric drugs, has led to their persistence in aquatic systems (bioaccumulation), since they are recalcitrant to conventional physical and chemical treatments typically used in wastewater treatment plants. An emerging environmental concern caused by the bioaccumulation of psychiatric drugs has been attributed to the potential ecological and toxicological risk that these medicines might have over human health, animals, and plants. Thus, by the application of biocatalysis-assisted techniques, it is possible to efficiently remove psychiatric drugs from water. Biocatalysis, is a widely employed and highly efficient process implemented in the biotransformation of a wide range of contaminants, since it has important differences in terms of catalytic behavior, compared to common treatment techniques, including photodegradation, Fenton, and thermal treatments, among others. Moreover, it is noticed the importance to monitor transformation products of degradation and biodegradation, since according to the applied removal technique, different toxic transformation products have been reported to appear after the application of physical and chemical procedures. In addition, this work deals with the discussion of differences existing between high- and low-income countries, according to their environmental regulations regarding waste management policies, especially waste of the drug industry.

The COVID-19 pandemic has challenged healthcare systems worldwide. Efforts in low-to-middle-income countries (LMICs) cannot keep stride with infection rates, especially during peaks. A strong international collaboration between Arizona State University (ASU), Tec de Monterrey (TEC), and Servicios de Agua y Drenaje de Monterrey (Local Water Utilities) is acting to integrate wastewater-based epidemiology (WBE) of SARS-CoV-2 in the region as a complementary approach to aid the healthcare system. Wastewater was collected from four sewer catchments in the Monterrey Metropolitan area in Mexico (pop. 4,643,232) from mid-April 2020 to February 2021 (44 weeks, n = 644). Raw wastewater was filtered and filter-concentrated, the RNA was extracted using columns, and the Charité/Berlin protocol was used for the RT-qPCR. The viral loads obtained between the first (June 2020) and second waves (February 2021) of the pandemic were similar; in contrast, the clinical cases were fewer during the first wave, indicating poor coverage. During the second wave of the pandemic, the SARS-CoV-2 quantification in wastewater increased 14 days earlier than the COVID-19 clinical cases reported. This is the first long-term WBE study in Mexico and demonstrates its value in pandemic management.

Endocrine disrupting chemicals are a group of contaminants that have severe effects on humans and animals when exposed, like cancer and alterations to the nervous and reproductive systems. The increasing concentrations of several endocrine disrupting chemicals in the environment are strongly related to anthropogenic activities, and as the population grows this problem becomes more relevant. Thus, wastewater is one of the main sources of endocrine disrupting chemicals, and the technologies employed during primary and secondary treatment in wastewater treatment plants cannot remove these contaminants. Due to this, researchers have tried to develop more efficient technologies for tertiary treatment of wastewater and reduce the concentration of endocrine disrupting chemicals discharged into the environment. Some of the most promising technologies include adsorption, ultrafiltration, advanced oxidation processes and biodegradation. The use of nanomaterials as adsorbents, catalysts, membranes and supports has played a key role in enhancing the efficiency of these technologies. The results showed that these technologies have great potential on the lab-scale, and even some of them have already been employed at some wastewater treatment plants. However, there are still some challenges to achieving a global implementation of these technologies, related to reducing the costs of materials and enhancing their current performance. The use of biomass/waste derived carbon materials and implementing hybrid technologies are accessible approaches for their implementation in tertiary treatment.

The pursuit of industrial and biotechnological revolutions has led to a growing problem of environmental pollution around the world. The fast-growing contamination of numerous environmental matrices is one of the major problems facing humanity due to the controlled and/or uncontrolled discharge of toxic elements from several industrial sectors. Due to several adverse consequences of persistent toxic elements, there is imperative to propose and deploy strategic measures and robust bioanalytical tools with greater efficiency and accuracy to detect a broader range of harmful pollutants. The expansion of pollution detecting tools can further aid real-time and on-site monitoring of the production and release of environmental contaminants in different industrial sectors. Considering the above critiques, the remarkable efforts of various regulatory/legalities authorities are urgently needed to tackle the growing environmental pollution dilemma efficiently. With key scientific and nanotechnological advancements, a unique modality has arisen in fluorescent sensing constructs to effectively sense and monitor this problem. The authentic scientific databases, including Scopus and PubMed, were used to perform the literature survey. For a said purpose, in this paper, a standardized methodology based on inclusion-exclusion criteria was followed to review the literature within the last ten years range to justify the scientific theme of the work and make sure to cover the recent and relevant literature contents.

Lactic acid (LA) is a chemical building block with wide applications in the food, cosmetics, and chemical industries. Its polymer polylactic acid further increases this range of applications as a green and biocompatible alternative to petrol-based plastics. Corn is the fourth largest crop in the world, and its residues represent a potentially renewable feedstock for industrial lactic acid production through simultaneous saccharification and fermentation (SSF). The main goal of this work is to summarize and compare the pretreatment methods, enzymatic formulations and microbial strains that have been combined in a SSF setup for bioconversion of corn crop residues into LA. Additionally, the main concerns of scaling-up and the innovation readiness level towards commercial implementation of this technology are also discussed. The analysis on commercial implementation renders the current state of SSF technology unsustainable, mainly due to high wastewater generation and saccharification costs. Nonetheless, there are promising strategies that are being tested and are focused on addressing these issues. The present work proves that the study and optimization of SSF as a biorefinery framework represents a step towards the adoption of potentially sustainable waste management practices.

Bionanocomposites based on natural bioactive entities have gained importance due to their abundance; renewable and environmentally benign nature; and outstanding properties with applied perspective. Additionally, their formulation with biological molecules with antimicrobial, antioxidant, and anticancer activities has been produced nowadays. The present review details the state of the art and the importance of this pyrrolic compound produced by microorganisms, with interest towards Serratia marcescens, including production strategies at a laboratory level and scale-up to bioreactors. Promising results of its biological activity have been reported to date, and the advances and applications in bionanocomposites are the most recent strategy to potentiate and to obtain new carriers for the transport and controlled release of prodigiosin. Prodigiosin, a bioactive secondary metabolite, produced by Serratia marcescens, is an effective proapoptotic agent against bacterial and fungal strains as well as cancer cell lines. Furthermore, this molecule presents antioxidant activity, which makes it ideal for treating wounds and promoting the general improvement of the immune system. Likewise, some of the characteristics of prodigiosin, such as hydrophobicity, limit its use for medical and biotechnological applications; however, this can be overcome by using it as a component of a bionanocomposite. This review focuses on the chemistry and the structure of the bionanocomposites currently developed using biorenewable resources. Moreover, the work illuminates recent developments in pyrrole-based bionanocomposites, with special insight to its application in the medical area.

PFAS are a very diverse group of anthropogenic chemicals used in various consumer and industrial products. The properties that characterize are their low degradability as well as their resistance to water, oil and heat. This results in their high persistence in the environment and bioaccumulation in different organisms, causing many adverse effects on the environment as well as in human health. Some of their effects remain unknown to this day. As there are thousands of registered PFAS, it is difficult to apply traditional technologies for an efficient removal and detection for all. This has made it difficult for wastewater treatment plants to remove or degrade PFAS before discharging the effluents into the environment. Also, monitoring these contaminants depends mostly on chromatography-based methods, which require expensive equipment and consumables, making it difficult to detect PFAS in the environment. The detection of PFAS in the environment, and the development of technologies to be implemented in tertiary treatment of wastewater treatment plants are topics of high concern. This study focuses on analyzing and discussing the mechanisms of occurrence, migration, transformation, and fate of PFAS in the environment, as well the main adverse effects in the environment and human health. The following work reviews the recent advances in the development of PFAS detection technologies (biosensors, electrochemical sensors, microfluidic devices), and removal/degradation methods (electrochemical degradation, enzymatic transformation, advanced oxidation, photocatalytic degradation). Understanding the risks to public health and identifying the routes of production, transportation, exposure to PFAS is extremely important to implement regulations for the detection and removal of PFAS in wastewater and the environment.

This special issue of Case Studies in Chemical and Environmental Engineering deals with the 21st century environmental engineering perspective to mitigate contaminants of emerging concern. Over the recent decades, a rampant industrial boom, urbanization, and an exponential increase in population growth resulted in numerous environmental impacts with water being one among the leading affected resources. All different kinds of pollutants, for example, organic compounds, heavy metals, dyes, pharmaceuticals and personal care products, pesticides, persistent/volatile organic compounds, petroleum hydrocarbons and toxic gases, have a paramount effect, either directly or indirectly, on human health and aquatic entities [1]. Human-made, agricultural, and industrial disposals play a substantial contribution in triggering wastewater pollution. Strategies for their affordable and efficient decontamination of these emerging pollutants have become the prime focus of academic researchers, industry, and government to constitute a sustainable human society. Classical techniques for determining and treatment of environmental contaminants are associated with several limitations, such as inefficiency, complex pretreatments, overall high process cost, generation of high sludge, and formation of highly toxic side-products [2]. Therefore, new, and state-of-the-art technologies possessing the advantages of detection, ease of use, and continuous degradation of environmental pollutants, are highly desirable.