The triple exposure nexus of microplastic particles, plastic-associated chemicals, and environmental pollutants from a human health perspective.

The presence of microplastics (MPs) is increasing at a dramatic rate globally, posing risks for exposure and subsequent potential adverse effects on human health. Apart from being physical objects, MP particles contain thousands of plastic-associated chemicals (i.e., monomers, chemical additives, and non-intentionally added substances) captured within the polymer matrix. These chemicals are often migrating from MPs and can be found in various environmental matrices and human food chains; increasing the risks for exposure and health effects. In addition to the physical and chemical attributes of MPs, plastic surfaces effectively bind exogenous chemicals, including environmental pollutants (e.g., heavy metals, persistent organic pollutants). Therefore, MPs can act as vectors of environmental pollution across air, drinking water, and food, further amplifying health risks posed by MP exposure. Critically, fragmentation of plastics in the environment increases the risk for interactions with cells, increases the presence of available surfaces to leach plastic-associated chemicals, and adsorb and transfer environmental pollutants. Hence, this review proposes the so-called triple exposure nexus approach to comprehensively map existing knowledge on interconnected health effects of MP particles, plastic-associated chemicals, and environmental pollutants. Based on the available data, there is a large knowledge gap in regard to the interactions and cumulative health effects of the triple exposure nexus. Each component of the triple nexus is known to induce genotoxicity, inflammation, and endocrine disruption, but knowledge about long-term and inter-individual health effects is lacking. Furthermore, MPs are not readily excreted from organisms after ingestion and they have been found accumulated in human blood, cardiac tissue, placenta, etc. Even though the number of studies on MPs-associated health impacts is increasing rapidly, this review underscores that there is a pressing necessity to achieve an integrated assessment of MPs' effects on human health in order to address existing and future knowledge gaps.

Assessment of heavy metals bioaccumulation in Silver Birch (Betula pendula Roth) from an AMD active, abandoned gold mine waste.

Acid mine drainage (AMD) is generally outlined as one of the largest environmental concerns, characterized by very low pH value of mine waste, heavy metals and high sulphate content. This extremely hostile environment reduces plant ability to develop and grow. Present study focuses on a silver birch (Betula pendula Roth), a pioneer species that grows on an extremely hostile gold mine waste, to investigate the bioaccumulation of rare metals (thallium (Tl) and indium (In)), as well as nine other more common heavy metals (bismuth (Bi), cadmium (Cd), cobalt (Co), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), silver (Ag) and zinc (Zn)), and to asses phytoextraction and phytostabilization potential of silver birch. Additionally, parameters determining AMD process and overall contamination (pH, electrical conductivity (EC), sulphates (SO42-), arsenic (As), iron (Fe), oxidation-reduction potential (ORP), turbidity, dissolved oxygen (DO), total dissolved solids (TDS), acidity, hardness, X-ray diffraction (XRD) and radioactivity) were determined in mine waste and drainage water samples. To assess the heavy metals bioaccumulation and mine waste status, statistical geochemical indices were determined: bioaccumulation factor (BCF), pollution load index (PLI), geochemical abundance index (GAI) and exposure index (EI). The results show that silver birch bioaccumulates the essential elements Cu, Ni, Mn and Zn, and the nonessential elements Tl (average BCF = 24.99), In (average BC = 23.01) and Pb (average BCF = 0.84). Investigated mine waste was enriched by Bi, Ag and Cd according to positive values of GAI index. Present research provides a novel insight into bioaccumulation of nonessential heavy metals in silver birches who grow on the extremely hostile mine waste, and they exhibit significant phytoremediation potential.

Surface engineered functional biomaterials for hazardous pollutants removal from aqueous environment.

The issue of water contamination by heavy metal ions as highly persistent pollutants with harmful influence primarily on biological systems, even in trace levels, has become a great environmental concern globally. Therefore, there is a need for the use of highly sensitive techniques or preconcentration methods for the removal of heavy metal ions at trace levels. Thus, this research investigates a novel approach by examining the possibility of using pomegranate (Punica granatum) peel layered material for the simultaneous preconcentration of seven heavy metal ions; Cd(II), Co(II), Cr(III), Cu(II), Mn(II), Ni(II) and Pb(II) from aqueous solution and three river water samples. The quantification of the heavy metals was performed by the means of FAAS technique. The characterization of biomaterial was performed by SEM/EDS, FTIR analysis and pHpzc determination before and after the remediation process. The reusability study as well as the influence of interfering ions (Ca, K, Mg, Na and Zn) were evaluated. The conditions of preconcentration by the column method included the optimization of solution pH (5), flow rate (1.5 mL/min), a dose of biosorbent (200 mg), type of the eluent (1 mol/L HNO3), sample volume (100 mL) and sorbent fraction (<0.25 mm). The biosorbent capacity ranged from 4.45 to 57.70 µmol/g for the investigated heavy metals. The practical relevance of this study is further extended by novel data regarding adsorbent cost analysis (17.49 $/mol). The Punica granatum sorbent represents a highly effective and economical biosorbent for the preconcentration of heavy metal ions for possible application in industrial sectors.

Low-dose and repeated exposure to nickel leads to bioaccumulation and cellular and metabolic alterations in quails.

Nickel (Ni) is a widespread environmental pollutant commonly released into effluent due to industrial activities, the use of fuels, or wastewater disposal. Many studies confirm the toxic effects of this heavy metal. However, there is a lack of knowledge and data on bioaccumulation patterns in tissues as well as cellular and molecular responses following the exposure of living organisms to Ni. In this study, Japanese quails were exposed to low (10 µg/L) and high (2000 µg/L) Ni concentrations in the form of nickel(II) chloride via drinking water. Sub-chronic exposure lasted 30 days while nominal concentrations represented average Ni content in drinking water (low dose) and average Ni levels in highly polluted aquatic environments (high dose). It was revealed that a high dose of Ni was correlated with increased water intake and decreased body weight. Overall, Ni exposure induced the development of microcytic anemia and alterations in measured blood indices. Moreover, Ni exposure impaired immunological activation as seen through the increased number of the white blood cells, increased heterophile/lymphocyte (H/L) ratio, and pronounced thrombocytosis. Ni elicited changes in the albumin, glucose, cholesterol, and triglyceride serum levels in a concentration-dependent manner. Alterations of plasma protein fractions suggested liver functional impairment while high levels of urea and creatinine indicated potential kidney injury. Granulation of heterophiles and an increase in erythroblasts in the bone marrow showed that the hematopoietic tissue was also impacted by Ni toxicity. On average each quail bioaccumulated 5.87 µg of Ni per gram of tissue. Moreover, the distribution and bioaccumulation of Ni in terms of relative concentration were as follows: feathers > kidneys > heart > liver > pectoral muscles. Assessed bioaccumulation levels and associated cellular and metabolic alterations have revealed new multilayer toxicological data that will help in the extrapolation of Ni toxicity in other vertebrates, including humans.

Highly effective sustainable membrane based cyanobacteria for uranium uptake from aqueous environment.

Wastewater from industrial process of uranium ore mining contains a large amount of this radioactive pollutant. Regarding the advantages of biosorption, it was found that varieties of biomasses such as agricultural waste, algae and fungi are effective for uranium removal. However, there is limited research on cyanobacteria, therefore, cyanobacteria, Anagnostidinema amphibium (CAA) was investigated by batch method for the first time for biosorption of uranium (VI). Optimization of biosorption parameters showed that maximum removal efficiency of 92.91% was reached at pH range of 9-11 with 50 mg of cyanobacteria to 100 mg/L U(VI) initial concentration, at 25 °C within 40 min. Used biosorbent exhibited very good selectivity for U(VI) ions and reusability in IV sorption/desorption cycles. Characterization of CAA surface was performed by FTIR, EDS, EDXRF and SEM analysis and it has shown various functional groups (CONH, COOH, OH, PO alkyl group) and that it is very rich in elements such as iron, potassium and calcium. In binary systems, contained of U(VI) and selected ions, CAA exhibits very good selectivity towards U(VI) ions. Kinetic data revealed the best accordance of experimental data with the pseudo-second-order model and isotherms data agreed with Freundlich model. Thermodynamic data implied that U(VI) biosorption process by A. amphibium exhibited spontaneity and modelling of the investigated process showed that the adsorption of uranium ions occurs mainly via peptidoglycan carboxyl groups. Overall results show that these cyanobacteria with a maximum sorption capacity of 324.94 mg/g have great potential for the processing of wastewater polluted with uranium (VI).

Advancements of sequencing batch biofilm reactor for slaughterhouse wastewater assisted with response surface methodology.

Slaughterhouse wastewater (SWW) contains a significant volume of highly polluted organic wastes. These include blood, fat, soluble proteins, colloidal particles, suspended materials, meat particles, and intestinal undigested food that consists of higher concentrations of organics such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrogen and phosphorus hence an efficient treatment is required before discharging into the water bodies. The effluent concentrations and performance of simultaneous sequential batch biofilm reactor (SBBR) with recycled plastic carrier media support are better than the local single-stage sequential batch reactor (SBR), which is lacking in the literature in terms of COD, NH3, NO3, and PO4 treatment efficiency. The present study reports a novel strategy to remove the above mentioned contaminants using an intermittently aerated SBBR with recycled plastic carrier media support along with simultaneous nitrification and denitrification. The central composite design was evaluated to optimize the treatment performance of seven different process variables including; different alternating conditions (Oxic/anoxic) for aeration cycles (3/2 h in a 6 h cycle, 6/5 h in a 12 h cycle and 9/8 h in an 18 h cycle) and hydraulic retention time (6, 12 and 18 h). The average removal efficiencies are 94.5% for NH3, 93% for NO3 and 90.1% for PO4, and 99% for COD. The study reveals that the denitrification in the post-anoxic phase was more efficient than the pre-anoxic phase for pollutant removal and maintaining higher quality effluent. The effluent concentrations and performance of simultaneous SBBR with recycled polyethylene carrier support media were better than local SBR system in terms of COD, NH3, NO3 and PO4 treatment efficiency. Results stipulated the suitability of SBBR for wastewater treatment and reusability as a sustainable approach for wastewater management under optimum conditions.

Thermodynamic valorisation of lignocellulosic biomass green sorbents for toxic pollutants removal.

Various toxic heavy metals have become hazardous to human health as well as the environment. This research has been focused on a biosorption/bioremoval process of chromium (III), copper (II) and lead (II) ions from an aqueous solution by utilizing lignocellulosic biomass of Citrus limon peel (CLP) powder. CLP powder biomass was selected based on dietary fibre components having greater potential to remove target heavy metal ions in order to purify wastewater by following the eco-friendly biosorption method. At optimum conditions, the observed maximum removal efficiency of 97.47, 87.13 and 95.71% for Cr, Cu and Pb ions, respectively, was observed. An investigation has been made as a work of pH, CLP amount and temperature. The presented bio-removal processes by prepared CLP biosorbent manifested as a temperature-independent. Langmuir isotherm model was found an excellent fit of the isotherm data for tested systems with the calculated biosorption capacities of 111.11 (Cr), 76.92 (Cu) and 100 (Pb) mg/g. The positive ΔH values for selected target heavy metal ions, except lead ions, confirmed that the reaction was spontaneous and endothermic. A cooperative mechanism of second-order and intraparticle diffusion models during the adsorption processes of all three target ions was established with a higher coefficient of determination and more closely anticipated take-up (adsorption capacity). Furthermore, the interaction of -OH and -COOH functional groups of CLP that have a major role in the removal of Cr, Cu and Pb ions from single-ion aqueous solution and/or a surface biosorption was confirmed based on the results presented by SEM-EDS and FTIR analysis. Analysis from XRD revealed peak corresponding to amorphous cellulose type I as observed by FT-IR analysis.

Synthesis of green nano sorbents for simultaneous preconcentration and recovery of heavy metals from water.

The wastewater containing Cd, Co, Fe, Cu, Cr, Mn, Ni and Pb ions are as trace metal pollutants. Water pollution caused by increment in industrialization and overpopulation reveals a major threat to human health. Adsorption is recognized as the effective and optimum method to remove water contaminations. The amorphous and porous form of silicon dioxide is silica gel widely used as an adsorbent. It can absorb moisture with traces of the target heavy metal ions. This research elaborates a simplistic, and reliable preconcentration column method highly developed for the determination of Cd2+, Fe3+, Co2+, Cr3+, Cu2+, Mn2+, Pb2+ and Ni2+ ions in model solutions and real water samples by flame atomic absorption spectrometry (FAAS). The proposed operation depends on the retention of the target ions from buffered model solutions on a silica gel filled up a column modified with vanadium(V) oxide sorbent followed by their desorption. SiO2/V2O5 is an efficient adsorbent due to its low cost, eco-friendly and high availability. The adsorbent morphological and interfacial physicochemical characterization was done using scanning electron microscopy, and Fourier transmission infrared spectroscopy, respectively. The 2.92 value achieved for the point of zero charges supports the experimentation for the heavy metal efficient adsorption. Quantitative recoveries were achieved at pH 10 with 50 mg of SiO2/V2O5 mass and adsorption capacity ranged from 28.96 µmol/g (Pb) to 214.86 µmol/g (Fe) with 1114.79 µmol/g in total. Simultaneous preconcentration effect was determined by the interference cations on the sorbent. The LOD varies from 8.42 to 50.56 µg/L and LOQ is achieved from 20.06 to 72.41 µg/L of 15 blank solutions. The developed preconcentration procedure was adequately implemented for the simultaneous analysis of eight metallic ions content in local river samples. The developed vanadium(V) oxide incorporated with silica gel is practicable as an economical and effective adsorbent to eliminate metallic ions from a liquid solution.

Heavy metals content in ashes of wood pellets and the health risk assessment related to their presence in the environment.

Efforts to reduce air pollution in developing countries may require increased use of biomass fuels. Even biomass fuels are a sustainable alternative to fossil fuels there is limited quantitative information concerning heavy metal content in their ashes. Therefore, this study focuses on the determination of the heavy metal concentrations in wood pellet ash obtained from the combustion of 10 pellet brans from Bosnia and Herzegovina and Italy, the effects of adding the ashes to soils, and the assessment of health risk assessment. Ash content was determined by gravimetric method. The amount and composition of ash remaining after combustion of wood pellets varies considerably according to the type of biomass and wood from which the pellet is made. Samples were prepared by wet digestion using HNO3, and heavy metals are determined by atomic absorption spectroscopy-flame and graphite furnace. The results showed that the lowest concentration in ashes was obtained for Co 0.01 mg kg-1 and the highest for Fe 571.63 mg kg-1. The Hazard Index (HI), calculated for non-cancerous substances for children was 2.23E-01, and the total Risk index was 4.54E-05. As for adults, HI was 1.51E-02, while the Risk index value was 3.21E-06. Human health risk calculated through HI and Risk index for children and adults associated with analyzed pellets is not of significant concern. The calculated enrichment factor and metal pollution index for wood pellet ashes indicate the risk of soil contamination with heavy metals. From this point of view, analyzed samples of ashes could be a serious contaminant of soil, so further monitoring is required.

Coupling of electrocoagulation and powder activated carbon for the treatment of sustainable wastewater.

The present research work is based on an electrochemical technique in combination with powdered activated carbon (PAC) for the removal of micropollutants by adsorption as an advanced stage purification step from effluents of pilot plant wastewater treatment plants (WWTP). The effluents of sedimentation tank comprised of wastewater plus PAC (WWPAC). The pilot plant mainly consists of two parts: the first one consists of electrocoagulation (EC) reactor, and the second consists of electrophoretic deposition (EPD) discs and electroflotation (EF) setup. The electrocoagulation (EC) reactor consisted of the electrode material (Al and Fe). Both types of electrodes have been tested with the outflow of sedimentation tank. The outflow from the sedimentation tank has been entered into the EC reactor for the determination of EC reactor efficacy for the successful accomplishment of EC process at the designed pilot plant for WW treatment. The effect of different operational parameters, PAC dosage (20 mg), electrode nature (Fe and Al) and current density (0.34-2.02 A/m2), has been studied to find out the optimum conditions. Sludge volume index (SVI) of the sludge, thermogravimetric (TG), differential thermal analyses (DTA) and particle size distribution (PSD) of the flocs generated after the EC process has also been studied. The turbidity, pH and conductivity of effluents before and after EC treatment have also been carried out. The research work performed detailed analysis of the wastewater effluents at pilot plant scale and gave promising results for future work in advance wastewater treatment direction.

Lead Exposure Influences Serum Biomarkers, Hepatocyte Survival, Bone Marrow Hematopoiesis, and the Reproductive Cycle in Japanese Quails.

Lead toxicity has been a hallmark issue of toxicology over the last decades. However, predictive and non-robust models did not provide complete data on low-dose lead interaction with the organism at different functional levels (e.g., blood-serum-liver-bone marrow-bursa fabricii-reproductive system axis). Japanese quails are an animal model with a strong immune system, making them suitable for the thorough assessment of in vivo chronic lead toxicity. In this study, we have exposed Japanese quails via water ingestion to 0.25 and 0.5 µg/mL lead(II) chloride (PbCl2) for 20 days and assessed blood cells, serum biomarkers, hepatocyte survival, bone marrow hematopoiesis, bursa fabricii, and lead accumulation in eggs. Blood cells passed through morphological alterations (loss and inversion of the erythrocyte nucleus, multiple erythrocyte and thrombocyte aggregation, lymphocyte degradation, and blast cell infiltration). In the serum, PbCl2 increased the activity of creatine kinase (CK) and lactate dehydrogenase (LDH); increased the level of cholesterol, sodium, creatinine, and urea; and reduced the level of proteins, triglycerides, chloride, potassium, calcium, and alkaline phosphatase (ALP) activity (P < 0.05). Liver tissue of the exposed animals exhibited apparent death of hepatocytes. In the bone marrow, macrophages and heterophils contained a vast number of the infiltrated/uptaken granules upon PbCl2 exposure. Ultimately, PbCl2 exposure elicited a series of events observed first in the blood and serum parameters and later translated to the hematopoietic centers.

Assessing hexavalent chromium tissue-specific accumulation patterns and induced physiological responses to probe chromium toxicity in Coturnix japonica quail.

Hexavalent chromium (Cr(VI)) is an environmental pollutant with vast mutagenic and carcinogenic potential. Various past and recent studies confirm the deleterious effects of Cr(VI) in different models, from invertebrates to mammalians. However, there is a lack of studies that comprehensively assess and correlate Cr(VI) accumulation patterns and the resulting physiological responses. Here we used an attractive toxicological model, male Japanese quail (Coturnix japonica), as an alternative probing system to evaluate Cr(VI) accumulation in the vital organs, including the brain, heart, kidneys, liver, and testes after 20 days of exposure to 1.2 µg/mL and 2.4 µg/mL potassium dichromate-K2Cr2O7 ingested in the form of drinking water. The observed effects were correlated with the shift in immune system readiness, hematological indices, serum biochemistry and enzyme activity. Regardless of the exposure dose, the Cr(VI) distribution and accumulation pattern in terms of relative Cr(VI) concentration in tissues was: testes > kidneys > liver > heart > brain. Moreover, Cr(VI) triggered the development of microcytic and hypochromic anemia and reduced the immune system's readiness to cope with challenges. Besides, serum biochemistry presented significant shifts, including reduction of serum electrolytes and proteins and an increase in creatine kinase (CK) and lactate dehydrogenase (LDH) activity. Our study provides novel toxicological data that can be translated to higher animal models to help in the extrapolation of Cr(VI) toxicity in humans.

PAHs in the urban air of Sarajevo: levels, sources, day/night variation, and human inhalation risk.

Polycyclic aromatic hydrocarbons (PAHs) are organic pollutants derived from pyrolysis and pyrosynthesis processes. Industrial activity, motor vehicle emission, and domestic combustion are the main sources of PAHs in the urban atmosphere. In this work, samples collected during the day and night in the urban area of Sarajevo are analyzed separately for gaseous and particle-bound PAHs; the possible origin of PAHs at the receptor site was suggested using different methods applied to the solid phase and to the total PAHs (gaseous + particulate phase). Finally, the risk level in Sarajevo associated to the carcinogenic character of the studied PAHs has been assessed. The result of this study suggests that (a) the total PAH concentrations were higher than those reported in other European cities; (b) the PAH daytime concentrations are higher than nocturnal concentrations: the sum of the PAH day/night ratios is 1.52 (gas) and 1.45 (particle phase); (c) stationary combustion and traffic were suggested to be the main sources of PAHs; (d) the average particle-bound benzo(a)pyrene (BaP) concentration (5.4 ng/m(3)) is higher than EU target annual value (1 ng/m(3)); and (e) PAH cancer risk exceeds the carcinogenic benchmark level recommended by the EPA mainly due to BaP during both the day and night periods.