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The natural radioactivity of 238U, 232Th and 40K was measured in water and sediment samples collected from Sidi Salem dam (Tunisia) and Aïn Dalia dam (Algeria) in the Tuniso-Algerian transboundary basin. The samples were measured using a TERRA detector of gamma, beta, and alpha rays, and atomic absorption and gamma-ray spectrometry were used to analyze the levels of radionuclides and toxic elements, respectively. Potentially toxic elements (Fe, Pb, Zn, Ni, Cr, Cu and Cd) and associated health risks in surface water and sediment of dams were investigated in this present study. The concentrations of Fe, Pb, Zn, Ni, Cr, Cu and Cd in surface water ranged from 5.430 to 9.700 mg·L−1, 0.022 to 0.168, 0.018 to 0.142, 0.065 to 0.366, BDL to 0.0351, BDL to 0.071 and BDL to 0.048 mg·L−1, respectively. In the sediments, the concentrations of Fe, Pb, Zn, Cu, Ni, Cd and Cr were of the order of 136.7, 3.41, 3.22, 0.213, 0.182, 0.15 mg·L−1 and BDL, respectively. The mean radioactivity rates in the water samples were 1.72, 0.068 and 94.6 Bq·L−1 for 238U, 232Th and 40K, respectively (Tunisia dam), and were 1.9, 0.09 and 131.43 Bq·L−1 for 238U, 232Th and 40K, respectively (Algeria dam). The mean 238U, 232Th and 40K radioactivity concentrations measured in the sediment samples were 2.67, 0.18 and 197.87 Bq·kg−1, respectively (Tunisian dam), and were 4.34, 0.27 and 287.61 Bq·kg−1, respectively (Algeria dam). The activity concentration of 40K was higher than that of 238U and 232Th for the water and sediment samples. The activity concentrations follow the order 40K > 238U > 232Th. The cumulative impact of these radio-geochemical elements can cause immediate serious problems in the ecosystem due to their high potential toxicity to the environment and human health in this study area and can be transposable to any other similar region. A good knowledge of monitoring quality and quantity for transboundary water resources and international collaborations are essential to safeguard human health (women's breast cancer, thyroid cancer, neurological impact) and avoid conflicts, especially during climatic upheavals of drought. [ABSTRACT FROM AUTHOR]

Proteins are essential to human healthwith enormous food applications. Despite their advantages, plant and animal proteins often exhibit limited molecular flexibility and poor solubility due to hydrogen bonds, hydrophobic interactions, and ionic interactions within their molecular structures. Thus, there is an urgent need to modify the rigid structure of proteins to enhance their stability and functional properties. Ultrasound-assisted ionic liquid (UA-IL) treatment for developing compound modification and producing proteins with excellent functional properties has received interest. However, no review specifically addresses the interactions between UA-ILs and proteins. Hence, this review focused on recent research advancements concerning the effects and potential reaction mechanisms of UA-ILs on the physicochemical properties (including particle size; primary, secondary, and tertiary structure; and surface morphology) as well as the functionality (such as solubility, emulsifying properties, and foaming ability) of proteins. Moreover, the safety evaluation of modified proteins was also discussed from various perspectives, such as acute and chronic toxicity, genotoxicity, cytotoxicity, and environmental and microbial toxicity. This review demonstrated that UA-IL treatment-induced protein structural changes significantly impact the functional characteristics of proteins. This treatment approach efficiently promotes protein structure stretching and spatial rearrangement through cavitation, thermal effects, and ionic interactions. As a result, the functional properties of modified proteins exhibited an obvious enhancement, thereby bringing more opportunities to utilize modified protein products in the food industry. Potential future directions for protein modification using UA-ILs were also proposed. [ABSTRACT FROM AUTHOR]

Indonesia as a megadiverse country and the third largest rice producer in the world utilizes neonicotinoids, a group of systemic insecticides reported to have polluted environmental waters and reduced the abundance of aquatic invertebrates mostly in sub-tropical and temperate countries. To date, no study and regulation on neonicotinoid pollution have been established in Indonesian environmental waters which situates in tropical zone. This research investigated neonicotinoid pollution in seven types of environmental waters of Indramayu Regency (one of the largest rice-producing areas in Indonesia), and assessed the potential risk and toxicity level of detected neonicotinoids to the tropical aquatic environment. Data collections included water sampling and analysis using LC/MS/MS. Results showed that the detection frequency of neonicotinoids was 53% (in 17 out of 32 samples), with imidacloprid and thiamethoxam being the most common compounds detected. The highest total concentration (140.26 ng/L) and the highest concentrations of imidacloprid, thiamethoxam, thiacloprid, dinotefuran, and acetamiprid (48.98 ng/L, 65.14 ng/L, 16.66 ng/L, 23.12 ng/L, and 25.04 ng/L, respectively) were detected in estuaries and mangrove areas. No sample was found to have neonicotinoid concentration above the acute and chronic toxicities of several tropical aquatic organisms assessed. About 19% of the samples contained imidacloprid exceeding the chronic thresholds regulated by The Netherlands, while 6% were also above The United States' regulation, thus encouraging the establishment of necessary actions to prevent unwanted disturbance to the aquatic ecosystem. This study delivered the first report of the occurrence of seven neonicotinoid compounds in seven types of Indonesian environmental waters. [ABSTRACT FROM AUTHOR]

The industrial areas are located near residential centers in the city of Arak and potentially toxic elements (PTEs) pollution is a serious threat to human health and living organisms in this area. Meanwhile, soil contamination by PTEs is one of the challenges in this region and various studies have been conducted in this area. Meta-analysis studies provide a comprehensive evaluation of the results of a subject. In the present study, soil contamination data for PTEs in the 11 years (2009 to 2020) were studied through the studies conducted in Arak. In this study, the risk, potential toxicity, and carcinogenic and non-carcinogenic risks of PETs were assessed using indices and mathematical relationships. Based on the results of pollution indices, the soil of Arak city in terms of PETs including Zn, Cd, Cr, Ni, As, Pb, Cu, and Hg were categorized into the polluted and highly polluted classes. The soil of the region in terms of PETs has significant ecological risk and acute toxicity. Cadmium, arsenic, and mercury showed the ecological risk of 49.3%, 23.2%, and 18.3% respectively, and nickel, chromium, and arsenic were responsible for 34.7%, 23.03%, and 22.07% of the toxicity potential of PETs in the soil. Arsenic, nickel, and chromium have the highest carcinogenic risk for children in both the ingestion and inhalation pathways, and chromium, arsenic, and nickel have the highest carcinogenic risk from the inhalation pathway for adults. According to the results, the most considerable PETs in the study area including As, Cd, and Pb, and the most important source of their emission in Arak are anthropogenic resources and industries.

It is a matter of common knowledge in the literature that engineered metal oxide nanoparticles have properties that are efficient for the design of innovative food/beverage packages. Although nanopackages have many benefits, there are circumstances when these materials are able to release nanoparticles into the food/beverage matrix. Once dispersed into food, engineered metal oxide nanoparticles travel through the gastrointestinal tract and subsequently enter human cells, where they display various behaviors influencing human health or wellbeing. This review article provides an insight into the antimicrobial mechanisms of metal oxide nanoparticles as essential for their benefits in food/beverage packaging and provides a discussion on the oral route of these nanoparticles from nanopackages to the human body. This contribution also highlights the potential toxicity of metal oxide nanoparticles for human health. The fact that only a small number of studies address the issue of food packaging based on engineered metal oxide nanoparticles should be particularly noted. [ABSTRACT FROM AUTHOR]

Indices of contamination (IC) are usually employed to assess the hazardousness associated with potentially toxic elements (PTE) from mining wastes (MW). For such, it is necessary to know the total concentrations of the PTE and local, regional, or global background or reference levels which are tolerable or acceptable threshold values for total content in soils. Although scientific literature is vast regarding the application of IC to MW, there is scarce research on the reference levels that must be employed in locations with no established comparison values. This study proposes basic reference levels for the global application of PTE contents in MW, leading to a global index of contamination (ICG). To this end, it was determined that the PTE to be assessed in MW should be As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Se, V, and Zn. From the analysis of background and baseline values for soils, reference values for the PTE compiled from worldwide standards or studies on soil and sediment evaluation, and PTE content in MW, a classification is proposed for ICG that considers MW as very low, low, moderate, high, and very high contamination potential. The findings presented herein can be helpful in the comparison of multiple types of MW, representing the contamination hazard by particle emission due to erosion processes that reach the soils or sediments of the surrounding environment. This evaluation can aid in the decision-making process regarding the reutilization of some types of MW that receive a low classification. [ABSTRACT FROM AUTHOR]

The industrial areas are located near residential centers in the city of Arak and potentially toxic elements (PTEs) pollution is a serious threat to human health and living organisms in this area. Meanwhile, soil contamination by PTEs is one of the challenges in this region and various studies have been conducted in this area. Meta-analysis studies provide a comprehensive evaluation of the results of a subject. In the present study, soil contamination data for PTEs in the 11 years (2009 to 2020) were studied through the studies conducted in Arak. In this study, the risk, potential toxicity, and carcinogenic and non-carcinogenic risks of PETs were assessed using indices and mathematical relationships. Based on the results of pollution indices, the soil of Arak city in terms of PETs including Zn, Cd, Cr, Ni, As, Pb, Cu, and Hg were categorized into the polluted and highly polluted classes. The soil of the region in terms of PETs has significant ecological risk and acute toxicity. Cadmium, arsenic, and mercury showed the ecological risk of 49.3%, 23.2%, and 18.3% respectively, and nickel, chromium, and arsenic were responsible for 34.7%, 23.03%, and 22.07% of the toxicity potential of PETs in the soil. Arsenic, nickel, and chromium have the highest carcinogenic risk for children in both the ingestion and inhalation pathways, and chromium, arsenic, and nickel have the highest carcinogenic risk from the inhalation pathway for adults. According to the results, the most considerable PETs in the study area including As, Cd, and Pb, and the most important source of their emission in Arak are anthropogenic resources and industries [ABSTRACT FROM AUTHOR]

Cigarette butts contain over 4000 toxic chemicals, including nicotine, tar, and heavy metals. More than 90 % of cigarettes sold today feature single-use plastic filters composed of cellulose acetate fibers and various additives. Cigarette butts are hazardous waste that pose significant risks to ecosystems and human health. Littered cigarette butts can act as an essential vehicle for toxic chemicals in the water environment. Cigarette butts contribute to gradual environmental degradation by releasing heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu), vanadium (V), nickel (Ni), and arsenic (As). Recent reports highlight the alarming increase in cigarette butt pollution on beaches, emphasizing the significance of commercial cigarette filters as single-use plastics and the primary contributors to this environmental threat. Given their potential toxicity, the research community has increasingly focused on understanding the profound impact of cigarette butt pollution on freshwater bodies, marine ecosystems, and terrestrial environments. However, there remains a considerable gap in knowledge regarding the extent of cigarette butt pollution, especially on Vietnam's beaches. While cigarette butts are a pervasive form of litter globally, little is known about their environmental effects, accumulation patterns, potential toxicity, and impacts on the coastline of Vietnam. This underscores the need for an in-depth investigation into this issue, expressing disappointment over the limited research conducted in coastal areas thus far. This article advocates for active participation from the scientific community to bridge this gap, asserting that collaborative research efforts will bring attention to and address the critical issue of cigarette butt pollution in Vietnam's regions and potential harm to natural ecosystems. Furthermore, enhancing research efforts to understand and mitigate cigarette butt pollution on Vietnam's beaches is crucial for achieving sustainable development goals (SDGs)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The presence of cyanobacteria in water for drinking and recreational purposes is considered problematic due to their bloom-forming and toxigenic potential. While most cyanotoxins are produced by extensively studied cyanobacteria, little is known about other abundant genera not usually assessed for their toxic potential. Here, a new isolate of Limnothrix redekei from an Italian drinking water reservoir was cultured and investigated using biological, chemical, and genomic methods. Compared to other Limnothrix spp., the isolate yielded high biomass productivity and was mainly constituted by proteins. The isolate had genomic features similar to those of the other 10 genomes of Limnothrix spp. published so far, regardless of their geographical origin. Most genes were implicated in primary metabolism (e.g. photosynthesis, nutrients transport, cell division), while <1 % of the genome was dedicated to secondary metabolism. Two regions encoding for a cyanobactin and a polyketide were found, whereas those for known cyanotoxins were absent. Toxicological investigations based on the crustacean Artemia sp. bioassay revealed potential toxicity of Limnothrix aqueous extracts (mortality >90 %). The highest toxicity was observed in a single fraction of the extract, whose UV spectrum presented carotenoid-like characteristics. Although the structure of the putative toxin was not yet elucidated, these findings pose the basis for further investigations on Limnothrix spp. toxicity, for which the observed toxic aqueous extracts could not exclude possible implications for ecosystems and humans through drinking water resources. [Display omitted] • Limnothrix redekei from Italy showed toxicity towards Artemia sp. nauplii. • Two regions encoding for a cyanobactin and a polyketide were found in the genome. • Cyanobactin synthesis was analytically confirmed while the polyketide was not found. • A toxic fraction was identified in aqueous extracts of the cyanobacterial biomass. • Multidisciplinary approaches expand the knowledge of less-studied cyanobacteria. [ABSTRACT FROM AUTHOR]

The beneficial roles of hydrochar in carbon sequestration and soil improvement are widely accepted. Despite few available reports regarding polycyclic aromatic hydrocarbons (PAHs) generated during preparation, their potential negative impacts on ecosystems remain a concern. A heating treatment method was employed in this study for rapidly removing PAHs and reducing the toxicity of corn stover-based hydrochar (CHC). The result showed total PAHs content (∑PAH) decreased and then sharply increased within the temperature range from 150 °C to 400 °C. The ∑PAH and related toxicity in CHC decreased by more than 80% under 200 °C heating temperature, compared with those in the untreated sample, representing the lowest microbial toxicity. Benzo(a)pyrene produced a significant influence on the ecological toxicity of the hydrochar among the 16 types of PAHs. The impact of thermal treatment on the composition, content, and toxicity of PAHs was significantly influenced by the adsorption, migration, and desorption of PAHs within hydrochar pores, as well as the disintegration and aggregation of large molecular polymers. The combination of hydrochar with carbonized waste heat and exhaust gas collection could be a promising method to efficiently and affordably reduce hydrochar ecological toxicity. [Display omitted] • Heating temperature of 200 °C reduced most part of PAHs content. • Biotoxicity of hydrochar should be ascribed mainly to benzo[ a ]pyrene. • PAHs variation may cause by volatilization and surface reactions. [ABSTRACT FROM AUTHOR]

Currently, there is a great demand for functional materials with effective pathogen-killing properties. In this research, we describe the use of green technology "reactive extrusion" for the synthesis of potent antimicrobial materials based on Ethylene-vinyl alcohol copolymer (EVOH). Herein, the antimicrobial agent, copper (II) acetate was used without pretreatment and introduced into the EVOH matrices at high temperatures. The thermal reaction of copper (II) acetate within the EVOH matrices and their effect on the thermal and thermomechanical properties of the polymer were investigated in regards to their concentration. The physicochemical, thermal, and rheological features, as well as, metal salt release kinetics were reported. The antimicrobial agent had significant effects on the properties of the matrix. Results showed a reduction in the glass transition temperatures and storage modulus of the materials in response to the incorporation of copper (II) acetate. Finally, the antimicrobial activity of the products was studied and demonstrated a possibility to create antimicrobial materials in a one-step, solvent-free extrusion process. [ABSTRACT FROM AUTHOR]

Excessive intake of benzaldehyde and its derivatives can cause irreversible damage to living organisms. Hence, benzaldehyde derivatives with different para-substitutions of push/pull electronic groups were chosen to investigate the effect of different substituent properties on the structure of human serum albumin (HSA). The binding constants, number of binding sites, major interaction forces, protein structural changes, and binding sites of benzaldehyde (BzH) and its derivatives (4-BzHD) with HSA in serum proteins were obtained based on multispectral and molecular docking techniques. The mechanism of BzH/4-BzHD interaction on HSA is mainly static quenching and is accompanied by the formation of a ground state complex. BzH/4-BzHD is bound to HSA in a 1:1 stoichiometric ratio. The interaction forces for the binding of BzH/4-BzHD to HSA are mainly hydrogen bonding and hydrophobic interaction, which are also accompanied by a small amount of electrostatic interactions. The effect of BzH/4-BzHD on HSA conformation follows: 4-Diethylaminobenzaldehyde (4-DBzH) > 4-Nitrobenzaldehyde (4-NBzH) > 4-Hydroxybenzaldehyde (4-HBzH) > 4-Acetaminobenzaldehyde (4-ABzH) > BzH, which means that the stronger push/pull electronic strength of the para-substituted benzaldehyde derivatives has a greater effect on HSA conformation. Furthermore, the concentration-lethality curves of different concentrations for BzH/4-BzHD on zebrafish verified above conclusion. This work provides a scientific basis for the risk assessment of benzaldehyde and its derivatives to the ecological environment and human health and for the environmental toxicological studies of benzaldehyde derivatives with different strengths of push/pull electron substitution. • The effect of 4-BzHD on HSA was analyzed by DFT, molecular docking and spectroscopy. • BzH/4-BzHD can change the microenvironment and conformation of HSA. • The potential toxicity of 4-BzHD increases with electronic strength of substituents. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are widely used in many consumer products, whereas their environmental behaviors in natural aquatic systems remain unknown, especially in natural brackish media. Therefore, it is urgent to investigate the environmental fate of AgNPs in natural brackish waters. Here, we investigated the stability of citrate-coated AgNPs in natural brackish water collected from 6 different sites with distinct salinities in the Xinglinwan Reservoir, located in Xiamen City, southeast China. The obtained results showed that AgNP colloids remained stable in low-salinity waters, which was mainly determined by the effects of dissolved organic matter (DOM) promoting the stability of the nanoparticles. However, the environmental fate of AgNPs in high-salinity waters was dominated by the salinity or ionic strength, especially the free ion concentrations of Cl−, SO 4 2−, or S2−, resulting in rapid sedimentation and dissolution. In addition, both DOM and salinity contributed to the environmental behavior of AgNPs in moderate-salinity waters, ultimately resulting in either colloidal stability or sedimentation. Overall, these results may reveal that AgNPs remain relatively stable for a long period in low-salinity natural waters, and that the stability might gradually decrease as AgNPs are transferred from freshwaters through brackish waters and eventually end up in seawater along the bay. Our findings also further indicate that the toxicity and potential risks of AgNPs may present more serious threats to the environment and organisms in natural freshwaters than in natural estuarine systems or seawater. Image 1 [ABSTRACT FROM AUTHOR]

Featured Application: This work uses a simple and reliable methodology applicable to other areas for the evaluation of residual contamination after bioremediation treatments. This study is focused on one of the most important spills that ever happened in Europe, the Aznalcóllar's mine spill. The extensive application of phytostabilization in the area led to the implementation of the Guadiamar Green Corridor (GGC). Soil physicochemical properties were analyzed and the total concentration of Pb, As, Zn and Cu was measured by X-ray fluorescence (XRF); bioassay using Lactuca sativa L. was applied to assess potential toxicity. Two decades after the accident, some soils affected by residual contamination continue to appear in the area. According to regulatory levels, Pb and As concentrations are exceeded in around 13%and 70%, respectively, in the uppermost part of the soils (first 10 cm). The change in soil properties after bioremediation treatment positively promoted the reduction in the potential mobility of pollutants by the increase in pH, CaCO3 content and organic carbon. Anyway, the bioassay with Lactuca sativa, indicated that around 25% of the soils showed toxicity by the reduction of the root elongation in relation to the control samples. Our results indicate that monitoring of the GGC is still needed, together with the application of soil recovery measures to reduce the potential toxicity in some sectors of the affected area. [ABSTRACT FROM AUTHOR]

Micro‐ and nanoplastics are generated from plastics and have negative impacts on the environment due to their high level of fragmentation. They can originate from various sources such as fragments, fibers and foams. The large proportion of the waste and resistance to degradation means micro‐ and nanoplastics have become a serious global environmental problem, but there are few studies on their potential toxicity for human health. In this review, we discussed routes of exposure and the potential effects of micro‐ and nanoplastics to human health. Human beings could mainly be exposed to micro‐ and nanoplastics orally and by inhalation. The possible toxic effects of plastic particles are due to the potential toxicity of plastics themselves, and their combined toxicity with leachable additives and adsorbed contaminants. The potential risks for human health focused on their gastrointestinal toxicity and liver toxicity. The toxic mechanisms could involve oxidative stress, inflammatory reactions and metabolism disorders. More studies are needed to carry out and explore the potential toxicological mechanisms of micro‐ and nanoplastics and evaluate the combined toxicity of their adsorbed contaminants. Micro‐ and nanoplastics pollution has become a serious global environmental problem, whereas there are few studies on their potential toxicity for human health. In thish review, we summarized the sources, production of microplastics and possible routes of human exposure and potential toxicity on human health. Oral intake is the main route for human exposure to microplastics, and the potential toxicity is focused on their gastrointestinal toxicity, liver toxicity, neurotoxicity and reproductive toxicity. [ABSTRACT FROM AUTHOR]

Proteins are essential to human health with enormous food applications. Despite their advantages, plant and animal proteins often exhibit limited molecular flexibility and poor solubility due to hydrogen bonds, hydrophobic interactions, and ionic interactions within their molecular structures. Thus, there is an urgent need to modify the rigid structure of proteins to enhance their stability and functional properties. Ultrasound-assisted ionic liquid (UA-IL) treatment for developing compound modification and producing proteins with excellent functional properties has received interest. However, no review specifically addresses the interactions between UA-ILs and proteins. Hence, this review focused on recent research advancements concerning the effects and potential reaction mechanisms of UA-ILs on the physicochemical properties (including particle size; primary, secondary, and tertiary structure; and surface morphology) as well as the functionality (such as solubility, emulsifying properties, and foaming ability) of proteins. Moreover, the safety evaluation of modified proteins was also discussed from various perspectives, such as acute and chronic toxicity, genotoxicity, cytotoxicity, and environmental and microbial toxicity. This review demonstrated that UA-IL treatment-induced protein structural changes significantly impact the functional characteristics of proteins. This treatment approach efficiently promotes protein structure stretching and spatial rearrangement through cavitation, thermal effects, and ionic interactions. As a result, the functional properties of modified proteins exhibited an obvious enhancement, thereby bringing more opportunities to utilize modified protein products in the food industry. Potential future directions for protein modification using UA-ILs were also proposed., (© 2023 Institute of Food Technologists®.)

Evidence continues to grow on potential health risks associated with Ginkgo biloba and its constituents. While biflavonoid is a subclass of the flavonoid family in Ginkgo biloba with a plenty of pharmacological properties, the potential toxicological effects of biflavonoids remains largely unknown. Thus, the aim of this study was to investigate the in vitro and in vivo toxicological effects of the biflavonoids from Ginkgo biloba (i.e., amentoflavone, sciadopitysin, ginkgetin, isoginkgetin, and bilobetin). In the in vitro cytotoxicity test, the five biflavonoids all reduced cell viability in a dose-dependent manner in human renal tubular epithelial cells (HK-2) and human normal hepatocytes (L-02), indicating they might have potential liver and kidney toxicity. In the in vivo experiments, after intragastrical administration of these biflavonoids at 20 mg·kg−1·d−1 for 7 days, serum biochemical analysis and histopathological examinations were performed. The activity of alkaline phosphatase was significantly increased after all the biflavonoid administrations and widespread hydropic degeneration of hepatocytes was observed in ginkgetin or bilobetin-treated mice. Moreover, the five biflavonoids all induced acute kidney injury in treated mice and the main pathological lesions were confirmed to the tubule, glomeruli, and interstitium injuries. As the in vitro and in vivo results suggested that these biflavonoids may be more toxic to the kidney than the liver, we further detected the mechanism of biflavonoids-induced nephrotoxicity. The increased TUNEL-positive cells were detected in kidney tissues of biflavonoids-treated mice, accompanied by elevated expression of proapoptotic protein BAX and unchanged levels of antiapoptotic protein BCL-2, indicating apoptosis was involved in biflavonoids-induced nephrotoxicity. Taken together, our results suggested that the five biflavonoids from Ginkgo biloba may have potential hepatic and renal toxicity and more attentions should be paid to ensure Ginkgo biloba preparations safety. [ABSTRACT FROM AUTHOR]

A total of 28 PCB congeners were determined using gas chromatography-mass spectrometry (GC–MS) in 46 surface soils collected from the Yellow River Delta Natural Reserve (YRDNR) and its adjacent area, China. The total concentrations of PCBs in the YRDNR ranged from 0.149 to 4.32 ng/g, with a mean concentration of 0.802 ng/g. Light PCB congeners predominated in the present research area, which may be attributed to the atmospheric transportation and were also associated with the recent contamination of unintentionally produced PCBs from industrial processes. In addition, PCB 126 and PCB 169 were found to be the major toxicity contributors of dioxin-like PCBs in the YRDNR, which should require special focus. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Populus nigra is a suitable bioindicator of atmospheric pollution and toxic impact. • Ag, As, Na, Sb, Sr, Ta, U, Zn concentrate at higher levels. • Highest potential toxic effect is observed near to the Northern Industrial Zone. • Zinc emissions contribute most to the toxicity index (about 99%). Abstract Changes in the environment like atmospheric trace element pollution can be mirrored in the elemental composition of indicator plants. They can contribute to distinguishing the degree of pollution, allocate sources of pollution, and identify their impact areas and polluting ingredients. However, ideally, the study should not be limited by these results. We should make more use of them to predict potential negative effects on the ecosystems and human health. In this research, an integrated study was implemented in Ust-Kamenogorsk city (Kazakhstan), in a territory with multicomponent, multifactor man-made impacts. Analyzing black poplar leaves we identified that Ag, As, Na, Sb, Sr, Ta, U, Zn concentrate at higher levels when compared with literature, their average contents in the dry weight of leaves are 0.08, 0.38, 936, 0.32, 193, 0.01, 0.08, 468 mg/kg respectively. We were able to show that the main source of Ag, Au, Sb, Zn is the lead-zinc plant "Kazzinc", while Be, Ta, U came from the Ulba metallurgical plant. As a result, we suggested that air pollution is the main parameter influencing the change of elemental composition of poplar leaves. Applying the results in life cycle impact assessment (LCIA) methodology also allows us to indicate not only the degree of contamination, but also to predict the degree of toxic exposure. The highest toxic effect on humans and ecosystems is observed in the impact zone of both companies, while zinc emissions contribute most to the toxicity index (about 99%). [ABSTRACT FROM AUTHOR]

In nature, a huge number of unregulated minerals fibers share the same characteristics as asbestos and therefore have potential adverse health effects. However, in addition to asbestos minerals, only fluoro-edenite and erionite are currently classified as toxic/pathogenic agents by the International Agency for Research on Cancer (IARC). Mordenite is one of the most abundant zeolites in nature and commonly occurs with a fibrous crystalline habit. The goal of this paper is to highlight how fibrous mordenite shares several common features with the well-known carcinogenic fibrous erionite. In particular, this study has shown that the morphology, biodurability, and surface characteristics of mordenite fibers are similar to those of erionite and asbestos. These properties make fibrous mordenite potentially toxic and exposure to its fibers can be associated with deadly diseases such as those associated with regulated mineral fibers. Since the presence of fibrous mordenite concerns widespread geological formations, this mineral fiber should be considered dangerous for health and the precautionary approach should be applied when this material is handled. Future in vitro and in vivo tests are necessary to provide further experimental confirmation of the outcome of this work.

This study is focused on one of the most important spills that ever happened in Europe, the Aznalcóllar’s mine spill. The extensive application of phytostabilization in the area led to the implementation of the Guadiamar Green Corridor (GGC). Soil physicochemical properties were analyzed and the total concentration of Pb, As, Zn and Cu was measured by X-ray fluorescence (XRF); bioassay using Lactuca sativa L. was applied to assess potential toxicity. Two decades after the accident, some soils affected by residual contamination continue to appear in the area. According to regulatory levels, Pb and As concentrations are exceeded in around 13%and 70%, respectively, in the uppermost part of the soils (first 10 cm). The change in soil properties after bioremediation treatment positively promoted the reduction in the potential mobility of pollutants by the increase in pH, CaCO3 content and organic carbon. Anyway, the bioassay with Lactuca sativa, indicated that around 25% of the soils showed toxicity by the reduction of the root elongation in relation to the control samples. Our results indicate that monitoring of the GGC is still needed, together with the application of soil recovery measures to reduce the potential toxicity in some sectors of the affected area.

Emerging contaminants (ECs) are synthetic or naturally occurring chemicals that are not commonly monitored despite having the potential of entering the environment and causing adverse ecological and/or human health effects. This study aimed to determine whether ECs are present in the surface waters of two rivers in Mato Grosso do Sul State, Brazil, and evaluate the effects of ECs mixtures at environmentally relevant concentrations on zebrafish ( Danio rerio ) gene expression. ECs concentrations were determined using solid-phase extraction and liquid chromatography-mass spectrometry. The ECs most frequently detected were caffeine, imidacloprid, 2-hydroxy atrazine, tebuthiuron, atrazine, and bisphenol A. We used these data to reconstruct ECs mixtures reflecting environmental concentrations, codenamed T1, T2, and T3. No effects were observed, so the concentrations were increased. After a preliminary evaluation of the No Observed Effect Concentration for each mixture, we analyzed changes in the expression of zebrafish target genes ( cyp1a , hsp70 , cat , sod1, tsh , cyp19a1a , cyp19a1b , cyp26b1 , casp8 , sox2 , cyb561d2 , and thrb ). cat was overrepresented in T1 and underrepresented in the other treatments. All of the mixtures induced the expression of cyp19a1b , which is a marker for (xeno-)estrogen exposure, and two of them increased the expression of cyp1a , which is used to indicate the presence of dioxin-like compounds. The rivers studied had low EC concentrations, and there was no indication of any harmful effects on the zebrafish. However, intensive agricultural activity may result in unsuspected peaks of EC pollution, and subsequent negative effects on living organisms. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is able to non-invasively treat and diagnose various cancers and nonmalignant diseases by combining light, oxygen, and photosensitizers (PSs). However, the application of PDT is hindered by poor water solubility and limited light-penetration depth of the currently available photosensitizers (PSs). Water solubility of PSs is crucial for designing pharmaceutical formulation and administration routes. Wavelength of light source at visible range normally has therapeutic depth less than 1 mm. In this review, focus is on the recent research progress of metal-based nanoparticles being applied in PDT. The potential toxicity of these nanoscales and future directions are further discussed. [ABSTRACT FROM AUTHOR]