Phytoremediation potential of switchgrass (Panicum virgatum), two United States native varieties, to remove bisphenol-A (BPA) from aqueous media

Anthropogenic stressors and the marine environment: From sources and impacts to solutions and mitigation

Human-released contaminants are often poorly understood wholistically in marine ecosystems. This review examines the sources, pathways, impacts on marine animals, and mitigation strategies of five pollutants (plastics, per- and polyfluoroalkyl substances, bisphenol compounds, ethynylestradiol, and petroleum hydrocarbons). Both abiotic and biotic mechanisms contribute to all five contaminants' movement. These pollutants cause short- and long-term effects on many biological processes genetically, molecularly, neurologically, physiologically, reproductively, and developmentally. We explore the extension of adverse outcome pathways to ecosystem effects by considering known inter-generational and trophic relations resulting in large-scale direct and indirect impacts. In doing so, we develop an understanding of their roles as environmental stressors in marine environments for targeted mitigation and future work. Ecosystems are interconnected and so international collaboration, standards, measures preceding mass production, and citizen involvement are required to protect and conserve marine life.

Physico-chemical and biological remediation techniques for the elimination of endocrine-disrupting hazardous chemicals

Due to their widespread occurrence and detrimental effects on human health and the environment, endocrine-disrupting hazardous chemicals (EDHCs) have become a significant concern. Therefore, numerous physicochemical and biological remediation techniques have been developed to eliminate EDHCs from various environmental matrices. This review paper aims to provide a comprehensive overview of the state-of-the-art remediation techniques for eliminating EDHCs. The physicochemical methods include adsorption, membrane filtration, photocatalysis, and advanced oxidation processes. The biological methods include biodegradation, phytoremediation, and microbial fuel cells. Each technique's effectiveness, advantages, limitations, and factors affecting their performance are discussed. The review also highlights recent developments and future perspectives in EDHCs remediation. This review provides valuable insights into selecting and optimizing remediation techniques for EDHCs in different environmental matrices.

Integrating Biochar, Bacteria, and Plants for Sustainable Remediation of Soils Contaminated with Organic Pollutants

The contamination of soil with organic pollutants has been accelerated by agricultural and industrial development and poses a major threat to global ecosystems and human health. Various chemical and physical techniques have been developed to remediate soils contaminated with organic pollutants, but challenges related to cost, efficacy, and toxic byproducts often limit their sustainability. Fortunately, phytoremediation, achieved through the use of plants and associated microbiomes, has shown great promise for tackling environmental pollution; this technology has been tested both in the laboratory and in the field. Plant-microbe interactions further promote the efficacy of phytoremediation, with plant growth-promoting bacteria (PGPB) often used to assist the remediation of organic pollutants. However, the efficiency of microbe-assisted phytoremediation can be impeded by (i) high concentrations of secondary toxins, (ii) the absence of a suitable sink for these toxins, (iii) nutrient limitations, (iv) the lack of continued release of microbial inocula, and (v) the lack of shelter or porous habitats for planktonic organisms. In this regard, biochar affords unparalleled positive attributes that make it a suitable bacterial carrier and soil health enhancer. We propose that several barriers can be overcome by integrating plants, PGPB, and biochar for the remediation of organic pollutants in soil. Here, we explore the mechanisms by which biochar and PGPB can assist plants in the remediation of organic pollutants in soils, and thereby improve soil health. We analyze the cost-effectiveness, feasibility, life cycle, and practicality of this integration for sustainable restoration and management of soil.

Groundwater contamination pathways of phthalates and bisphenol A: origin, characteristics, transport, and fate - A review

Phthalic acid esters (PAEs) or phthalates and bisphenol A (BPA) are emerging organic contaminants (EOCs) that may harm biota and human health. Humans can be exposed to these contaminants by drinking water consumption from water sources such as groundwater. Before their presence in aquifer systems, phthalates and BPA can be found in many matrices due to anthropogenic activities, which result in long-term transport to groundwater reservoirs by different mechanisms and reaction processes. The worldwide occurrence of phthalates and BPA concentrations in groundwater have ranged from 0.1 × 10^-3 to 3 203.33 µg L^-1 and from 0.09 × 10^-3 to 228.04 µg L^-1, respectively. Therefore, the aim of this review is to describe the groundwater contamination pathways of phthalates and BPA from the main environmental sources to groundwater. Overall, this article provides an overview that integrates phthalate and BPA environmental cycling, from their origin to human reception via groundwater consumption. Additionally, in this review, the readers can use the information provided as a principal basis for existing policy ratification and for governments to develop legislation that may incorporate these endocrine disrupting compounds (EDCs) as priority contaminants. Indeed, this may trigger the enactment of regulatory guidelines and public policies that help to reduce the exposure of these EDCs in humans by drinking water consumption.

Phytoremediation potential, antioxidant response, photosynthetic behavior and rhizosphere bacterial community adaptation of tobacco (Nicotiana tabacum L.) in a bisphenol A-contaminated soil

Bisphenol A (BPA) is an emerging organic pollutant, widely distributed and frequently detected in soil in recent years. BPA toxicity is a problem that needs to be solved in terms of both human health and agricultural production. Up to now, the toxic effect of BPA and its mechanism of action on plants, as well as the possibility of using plants to remediate BPA-contaminated soil, remain to be explored. In this study, six treatment groups were set up to evaluate the effects of different concentrations of BPA on the germination and growth of tobacco (Nicotiana tabacum L.) by medium experiments. Furthermore, the representative indexes of photosynthetic and antioxidant system were determined. Meanwhile, tobacco seedlings were cultivated in soil to further explore the effects of BPA on rhizosphere soil enzyme activity and bacterial community structure with or without 100 mg/kg BPA exposure. The enhancement of BPA removal efficiency from soil by phytoremediation using tobacco plants would also be estimated. Our results showed that high doses of BPA in solid medium remarkably inhibited tobacco seedling growth, and its toxicology effect was positively correlated with BPA concentration, while lower BPA exposure (< 20 mg/L) had little limitation on tobacco growth and induced hormesis effect, which was reflected mainly in the increase of root length. In pot experiments, the reducing of chlorophyll content (36.4%) and net photosynthetic rate (41.2%) meant the inhibition of tobacco photosynthetic process due to high concentration of BPA exposure (100 mg/kg) in soil. The increase of H2O2 and O2- content suggested that BPA could destroy the balance of reactive oxygen species (ROS) in plants. However, tobacco plants still presented a high removal efficiency of BPA at the concentration of 100 mg/kg in soil, which could reach to 80% within 30 days. Furthermore, it was indicated that tobacco cultivation changed the structure of rhizosphere soil bacterial communities and the relative abundance of some valuable strains, including Proteobacteria, Acidobacteria and other strains, which might be participated in the BPA removal process. In addition, the tobacco-soil microbial system had the potential to reverse the negative effects caused by BPA through stimulating microorganism associated with soil nutrient cycling. In summary, tobacco is a competitive plant in phytoremediation of BPA-contaminated soil, though the growth of tobacco could be inhibited at high concentration of BPA. Moreover, tobacco might promote the removal efficiency of BPA by regulating the rhizosphere bacteria communities.

Bioremediation of bisphenol A found in industrial wastewater using Trametes versicolor (TV) laccase nanoemulsion-based bead organogel in packed bed reactor

Bisphenol A (BPA) is one of the toxic chemicals, which is widely used for manufacturing epoxy, polyester resin, and polycarbonates. These materials are extensively used in manufacturing of reusable bottles, baby bottles, dental sealants, various medical devices, and so forth. Moreover, canned and packaged foods are sources of bisphenol A, which is unknowingly consumed by many people worldwide. Its endocrine disrupting and teratogenic properties impose potential risk to the wildlife and human health. BPA has been linked to reproductive, metabolic, and immunity disorders in humans. Regardless of BPA ban in reusable and baby bottles, annually, 15 billion pounds of BPA still being produced. BPA pollution and its cleanup are major challenges. Therefore, it is essential to develop a suitable strategy to bioremediate BPA. The Trametes versicolor (TV) laccase-based nanoemulsion calcium alginate bead organogel was able to transform 94% of BPA within 2 h of treatment. Organogel showed 60% of BPA removal from actual industrial wastewater in packed bed batch reactor and 67% of BPA removal in continuous flow packed bed reactor. The biological oxygen demand (BOD) of treated industrial effluent was 14 mg/L, which is very much less than untreated effluent's BOD, which was 48 mg/L. The chemical oxygen demand of industrial effluent was 1240 mg/ml, and treated effluent was 248 mg/L, respectively. Hence, application of nanoemulsion-based organogel in packed bed reactor found to be a potential candidate for the bioremediation of industrial effluent containing BPA. PRACTITIONER POINTS: The TV laccase-based nanoemulsion calcium alginate bead organogel was able to transform 94% of BPA. Organogel showed 67% of BPA removal from industrial wastewater in continuous flow packed bed reactor. The nanoemulsion-based organogel in packed bed reactor found to be potential candidate for the bioremediation of industrial effluent containing BPA.

Phytoremediation as an effective tool to handle emerging contaminants

Phytoremediation is a process which effectively uses plants as a tool to remove, detoxify or immobilize contaminants. It has been an eco-friendly and cost-effective technique to clean contaminated environments. The contaminants from various sources have caused an irreversible damage to all the biotic factors in the biosphere. Bioremediation has become an indispensable strategy in reclaiming or rehabilitating the environment that was damaged by the contaminants. The process of bioremediation has been extensively used for the past few decades to neutralize toxic contaminants, but the results have not been satisfactory due to the lack of cost-effectiveness, production of byproducts that are toxic and requirement of large landscape. Phytoremediation helps in treating chemical pollutants on two broad categories namely, emerging organic pollutants (EOPs) and emerging inorganic pollutants (EIOPs) under in situ conditions. The EOPs are produced from pharmaceutical, chemical and synthetic polymer industries, which have potential to pollute water and soil environments. Similarly, EIOPs are generated during mining operations, transportations and industries involved in urban development. Among the EIOPs, it has been noticed that there is pollution due to heavy metals, radioactive waste production and electronic waste in urban centers. Moreover, in recent times phytoremediation has been recognized as a feasible method to treat biological contaminants. Since remediation of soil and water is very important to preserve natural habitats and ecosystems, it is necessary to devise new strategies in using plants as a tool for remediation. In this review, we focus on recent advancements in phytoremediation strategies that could be utilized to mitigate the adverse effects of emerging contaminants without affecting the environment.

Adsorptive Behavior of an Activated Carbon for Bisphenol A Removal in Single and Binary (Bisphenol A—Heavy Metal) Solutions

Bisphenol A (BPA) is an extensively produced and consumed chemical in the world. Due to its widespread use, contamination by this pollutant has increased in recent years, reaching a critical environmental point. This work investigates the feasibility of bisphenol A adsorption from industrial wastewater solutions, testing the reduction of bisphenol A in synthetic solutions by a commercial activated carbon, AC-40, in batch mode. Besides, mixtures of bisphenol A and different heavy metal cations were also studied. So far, no works have reported a complete study about bisphenol A removal by this activated carbon including the use of this material to remove BPA in the presence of metal cations. First, adsorption experiments were performed in batch changing pH, dose of adsorbent, initial bisphenol A concentration and contact time. Results showed greater retention of bisphenol A by increasing the acidity of the medium. Further, the percentage of bisphenol A adsorbed increased with increasing contact time. The selected conditions for the rest of the experiments were pH 5 and a contact time of 48 h. In addition, an increase in retention of bisphenol A when the dose of adsorbent increased was observed. Then, specific experiments were carried out to define the kinetics and the adsorption isotherm. Equilibrium data were adequately fitted to a Langmuir isotherm and the kinetics data fitted well to the pseudo-second-order model. The maximum adsorption capacity provided by Langmuir model was 94.34 mg/g. Finally, the effect of the presence of other heavy metals in water solution on the adsorption of bisphenol A was analyzed. Binary tests revealed competition between the adsorbates and a significant selectivity toward bisphenol A. Finally, the study of the adsorption performance in three consecutive adsorption–desorption cycles showed efficiencies higher than 90% in all cycles, indicating that the activated carbon has good reusability.