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A study was conducted on 31 surface sediments located in different sectors of the Egyptian Mediterranean coast. The sediments were analyzed for their pollution levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The sediments were collected from various depths in harbors, coastal lakes, bays, and lagoons, covering the southeastern Mediterranean of the Nile Delta region. The study aimed at determining the distribution, origin, and potential ecological impact of OCP and PCB pollutants. The researchers used the SRM method of GC-MS/MS to measure the concentration of 18 PCBs and 16 OCPs residues. The study found that the total concentration of OCPs in the samples ranged from 3.091 to 20.512 ng/g, with a mean of 8.749 ± 3.677 ng/g. The total concentration of PCB residues ranged from 2.926 to 20.77 ng/g, with a mean of 5.68 ± 3.282 ng/g. The concentration of DDTs exceeded the effect range low (ERL) (1.00) and threshold effect level (TEL) (1.19) in several stations, but it was still below the effect range median (ERM) (7.00) and the probable effect level (PEL) (4.77). This indicates a low ecological risk. The principal component analysis (PCA) was also conducted to determine the sources of all pollutants in the sediment. The PCA showed significant correlations between the concentrations of Gama-HCH and Beta-HCH (0.741), suggesting similar sources. PRACTITIONER POINTS: OCPs and PCBs residues were analyzed in the sediment of the southeastern Mediterranean. The concentration, existence, and causes of OCPs and PCBs were investigated. OCPs and PCBs ecological risk and ecotoxicological calculation were investigated in detail. Cluster analysis, PCA, and correlation coefficient were also investigated.

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Modern agriculture is mainly based on the use of pesticides to protect crops but their efficiency is very low, in fact, most of them reach water or soil ecosystems causing pollution and health hazards to non-target organisms. Fungicide triazoles and strobilurins based are the most widely used and require a specific effort to investigate toxicological effects on non-target species. This study evaluates the toxic effects of four commercial fungicides Prosaro® (tebuconazole and prothioconazole), Amistar®Xtra (azoxystrobin and cyproconazole), Mirador® (azoxystrobin) and Icarus® (Tebuconazole) on Eisenia fetida using several biomarkers: lipid peroxidation (LPO), catalase activity (CAT), glutathione S-transferase (GST), total glutathione (GSHt), DNA fragmentation (comet assay) and lysozyme activity tested for the first time in E. fetida. The exposure to Mirador® and AmistarXtra® caused an imbalance of ROS species, leading to the inhibition of the immune system. AmistarXtra® and Prosaro®, composed of two active ingredients, induced significant DNA alteration, indicating genotoxic effects. This study broadened our knowledge of the effects of pesticide product formulations on earthworms and showed the need for improvement in the evaluation of toxicological risk deriving from the changing of physicochemical and toxicological properties that occur when a commercial formulation contains more than one active ingredient and several unknown co-formulants.

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Increasing of tobacco consumption around the world has led to the production of a large volume of waterpipe wastewater that enter the environment (e.g., coastal areas)and threaten aquatic creatures. However, until now, no research has been carried out on the amounts of monocyclic and polycyclic aromatic hydrocarbons (PAHs) in hookah wastewater. In the current study, the levels of PAHs and BTEX compounds in waterpipe wastewater resulting from the use of different tobacco brands were determined and their eco-toxicological effects were also evaluated. The mean levels of Æ©PAHs in waterpipe wastewater of Al Tawareg, Al-Fakher, Nakhla, Tangiers and traditional tobacco brands samples were 3.48 ± 1.65, 3.33 ± 1.52, 3.08 ± 1.25, 2.41 ± 0.87 and 0.70 ± 0.13 µg/L, respectively. The mean levels of Æ©BTEX in waterpipe wastewater of Al Tawareg, Al-Fakher, Nakhla, Tangiers and traditional tobacco brands samples were also 2.53 ± 0.61, 2.65 ± 0.78, 2.51 ± 0.72, 2.35 ± 0.56, and 0.78 ± 0.12 µg/L, respectively. The maximum level of PAHs and BTEX compounds in all brands/flavors samples were for naphthalene (Naph) and toluene, respectively. The concentrations of some PAHs (fluoranthene (Flrt), anthracene (Ant), benzo(b)fluoranthene (BbF), benzo(b)fluoranthene (BkF), benzo (g,h,i)perylene (BghiP) and dibenzo (a, h) anthracene (DahA)) and BTEX compounds (benzene) in the waterpipe wastewater samples were more than recommended guidelines and standards by the international reputable organizations such as World Health Organization (WHO) for water quality. Waterpipe wastewater can be introduced as an important origin for the release of these dangerous contaminants into the environmental matrixes. Therefore, more stringent regulations should be considered for the safe disposal of such hazardous wastes including waterpipe wastewater.

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In vitro testing methods offer valuable insights into the corrosion vulnerability of metal implants and enable prompt comparison between devices. However, they fall short in predicting the extent of leaching and the biodistribution of implant byproducts under in vivo conditions. Physiologically based toxicokinetic (PBTK) models are capable of quantitatively establishing such correlations and therefore provide a powerful tool in advancing nonclinical methods to test medical implants and assess patient exposure to implant debris. In this study, we present a multicompartment PBTK model and a simulation engine for toxicological risk assessment of vascular stents. The mathematical model consists of a detailed set of constitutive equations that describe the transfer of nickel ions from the device to peri-implant tissue and circulation and the nickel mass exchange between blood and the various tissues/organs and excreta. Model parameterization was performed using (1) in-house-produced data from immersion testing to compute the device-specific diffusion parameters and (2) full-scale animal in situ implantation studies to extract the mammalian-specific biokinetic functions that characterize the time-dependent biodistribution of the released ions. The PBTK model was put to the test using a simulation engine to estimate the concentration-time profiles, along with confidence intervals through probabilistic Monte Carlo, of nickel ions leaching from the implanted devices and determine if permissible exposure limits are exceeded. The model-derived output demonstrated prognostic conformity with reported experimental data, indicating that it may provide the basis for the broader use of modeling and simulation tools to guide the optimal design of implantable devices in compliance with exposure limits and other regulatory requirements.

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ISO 10993-1:2018 describes evaluating the biocompatibility profile of a medical device from a risk-based approach. This standard details the battery of information that should be considered within the assessment of a device, including raw material composition data, manufacturing processes, and endpoint testing. The ISO 10993/18562 series requires worst-case assumptions and exposure scenarios to be used in the evaluation, which may result in an over-estimation of patient safety risk. Currently, biocompatibility assessments evaluate each data set independently, and the consequence of this individualized assessment of exaggerated inputs is potential false alarms regarding patient safety. To evaluate these safety concerns, the ISO standards indicate that professional judgement should be used to estimate patient risk but does not provide guidance on incorporating a holistic review of the data into the risk assessment. Recalibrating these worst-case data to evaluate them in a weight-of-evidence (WoE) approach may provide a more realistic data set to determine actual patient risk. This proposed WoE framework combines understanding data applicability with a method for gauging the strength of data that can provide additional support for the final safety conclusion. Using a WoE framework will allow risk assessors to contextualize the data and utilize it to comprehensively estimate patient safety.

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Antibiotics in aquatic systems of developing countries are a growing concern, particularly with the potential ecological risks and emergence of antimicrobial resistance. In Pakistan, antibiotics are widely consumed and released untreated into rivers, however, there is little information on their occurrence and potential risks. In this study, the concentrations and risk assessment of three commonly consumed antibiotics, ciprofloxacin (CIP), amoxicillin (AMX), and cefixime (CFM) belonging to different classes of fluoroquinolone, penicillin, and cephalosporin respectively were investigated in the Kabul River and its two tributaries, Bara River and Shah Alam River in the northwest region of the country. Composite samples were collected in different sampling campaigns and analyzed using the LC-ESI-MS/MS technique. All three antibiotics were found in higher concentrations ranging from 410 to 1810 ng/L, 180-850 ng/L, and 120-600 ng/L for CIP, AMX, and CFM respectively. The Friedman and Wilcoxon signed-ranked tests revealed insignificant differences in average concentrations of each antibiotic in the three rivers and the Pearson Correlation showed a significant positive correlation of CIP with both AMX and CFM indicating their similar pollution sources. Ecotoxicological risk assessment showed a higher risk to algae and bacteria (P. putida) in the rivers with CIP posing a greater risk. The potential risk of antimicrobial resistance development (ARD) was higher in all the three rivers, particularly in Kabul River where maximum risk quotients (RQARD) of 28.3, 9.4 and 3.4 were noted for CIP, CFM and AMX respectively. The human health (HH) risk was insignificant, though the RQHH was higher for the lower age groups (0-3 months). In addition, the combined flux of the antibiotics in the Kabul River was estimated as 59 tons/year with CIP having a significant flux relative to the other antibiotics.

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Aim: To perform an exposure assessment of arsenic, manganese, mercury and lead levels in hair samples from children from poor neighborhoods. Materials & methods: A total of 38 Caucasian children were recruited with the consent of their parents or tutors. Determinations were performed by atomic absorption spectrometry. Results & conclusion: Results were 0.045-0.12 µg/g-1 (arsenic), 0.56-2.05 µg/g-1 (manganese) and 0.34-27.8 µg/g-1 (lead). Lead results did not correlate with those previously reported in blood from the same individuals, suggesting that hair is not useful for exposure assessment of this contaminant. Mercury was determined for the first time in Uruguayan children showing levels <0.083 µg/g-1. Results revealed low-to-moderate metal exposure, except for some high lead findings.

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In the last decades, the interest for anaerobic process as a mainstream treatment of municipal wastewater increased due to the development of high-rate anaerobic bioreactors able to achieve removal kinetics comparable to the aerobic ones. Moreover, they have the additional advantages of energy production, nutrient recovery and reduced excess sludge yield, which are interesting features in the frame of sustainability wastewater treatment goals. These appealing factors increased the research demand to evaluate the potential of the anaerobic removal for contaminants of emerging concern (CECs) in municipal wastewater. However, despite the growing interest for the subject, literature is still fragmentary and reviews are mainly focused on specific technologies and target compounds or groups of compounds. We propose this review with the main objectives of presenting the state of knowledge, the performances of anaerobic systems for CECs' removal and, more important, to give the reader guidelines for optimal treatment selection. In the first part, a general overview of the investigated technologies at different scale, with a special focus on the recently proposed enhancements, is presented. Collected data are analysed to select the target CECs and the analysis results employed to define the optimal technological solution for their removal. A first novelty element of the paper is the original procedure for contaminant selection consisting of a risk assessment tool for CECs, based on their frequency of detection, concentration and potential for biosorption in wastewater treatment plants. Data of selected target CECs are combined with compound and technology performance data to implement a flowchart tool to evaluate the optimal treatment strategy, which constitute another, even more important, novelty element of this study.

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Traditional herbal medicinal products (THMP) with Thymi herba (Thymus vulgaris L. and Thymus zygis L.) are very popular among the European population. The idea of our study was the toxicological analysis of lead impurities in THMP with Thymi herba obtained from Polish pharmacies. For this purpose, we prepared the impurity profiles and comprehensive toxicological risk assessment. The Pb impurity profiles show lead impurities in all samples investigated (in the range: 2.15-6.99 µg/L). The estimations of Pb impurities in the single dose (32.25-105.01 ng/single dose) and in the daily dose (64.50-210.00 ng/day) were based on the posology recommended by the manufacturers. All the results obtained meet the standards of the ICH Q3D (R1) guideline on elemental impurities according to the levels of Pb. It can be concluded that all investigated THMPs with Thymi herba available in Poland should not represent any health risk to adults.

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Tea is the world's most common drink after water, and the world's annual sales exceed $43 billion, of which more than $11 billion is green tea (Camellia sinensis (L.)). Increasing evidence continues to show that green tea consumption and its ingredients have a variety of potential health benefits. The aim of the study was to control and assess the toxicological risk (TRA) of three heavy metals (As, Pb, and Cd) in infusions of green tea (n = 12) from Polish markets. We applied the method of inductive coupled plasma mass spectrometry (ICP-MS) to determine the selected heavy metal and designed a specific toxicological risk assessment with three crucial tiers. The first tier of our strategy was to determine the elements investigated (heavy metal impurities, µg/L). The second step was to estimate the weekly intake of green tea infusions (µg/week) based on weekly consumption. The third tier was to estimate the weekly intake per weight (µg/L/week/bw), based on the average weekly intake of green tea infusion per adult compared to the provisional weekly intake (PTWI) established by the FAO/WHO Joint Food Additives Expert Committee (JECFA). The levels of the investigated heavy metals occur at different levels in all of the investigated green tea infusions. The heavy metal profile indicated that As (0.0721-10.585 µg/L), Pb (0.386-1.695 µg/L), and Cd (0.126-0.346 µg/L) were present in all samples. Basic analysis of general content shows that As (average = 0.325 µg/L) was at a level similar to Cd (average = 0.214 µg/L). Surprisingly, the Pb content (average 0.891 µg/L) was approximately 2.75-4 times higher than that of As and Cd, respectively. The application of our proposed safety assessment methodology (three tiers) provides satisfactory results for regulatory purposes. The evaluation of the investigated heavy metals in all products analysed from green tea samples (infusions) showed that there were no health hazards to consumers due to weekly exposure. The results indicated that after drinking green tea infusions from Polish markets, the amount of investigated elements in weekly doses does not represent any health risks to consumers.

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Horses are excellent bioindicators for the assessment of environmental pollution. The aim of this study was to evaluate the levels and potential bioaccumulation of 28 mineral elements in 75 horse whole blood samples collected from five pollution-prone areas of Sicily, Italy. A direct mercury analyzer (DMA-80) was used for Hg determination, and an inductively coupled plasma mass spectrometer (ICP-MS) for all other elements. A one-way ANOVA test, followed by Bonferroni's multiple comparison for post hoc comparison, was applied to assess statistically significant differences between mineral elements and the five experimental groups. The levels of mineral elements in hay and concentrate were below the limits set by Regulation No. 744/2012. The mineral content of whole blood samples was slightly influenced by the region of origin of the horse. p values < 0.05 were statistically meaningful. However, the concentrations of mineral elements in horses' whole blood remained within reference ranges. In conclusion, the present study shows that the mineral content does not represent a toxicological risk for the analyzed horses. In addition, the study areas did not appear to show a high mineral element contamination.

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Local and systemic contamination caused by metal ions leaching from medical device materials is a significant and continuing health problem. The increasing need for verification and validation, and the imposition of stringent government regulations to ensure that the products comply with the quality, safety, and performance standards, have led regulatory bodies worldwide to strongly recommend the use of modeling and simulation tools to support medical device submissions. A previously published physiologically based toxicokinetic (PBTK) model, is here expanded and enriched by an additional separate tissue compartment to better resemble normal physiology and by the introduction of time-dependent functions to describe all biokinetic parameters. The new model is exercised in conjunction with state-of-the-art probabilistic, Monte Carlo methodology to calculate the predictions' confidence intervals and incorporate variability associated with toxicological biodistribution studies. The quantitative consistency of the model-derived predictions is validated against reported data following the implantation of nickel-containing cardiovascular devices in humans and minipigs. Finally, a new methodology for compartmental toxicological risk assessment is presented that can be used for forward or reverse dosimetry. Our work is aimed at providing a computational tool to optimize the device design characteristics and safeguard that the substances released do not exceed permissible exposure limits.

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This article focusses on the environmental implications of low-cost jewelry for adults from Chinese e-commerce platforms ((n = 8) with heavy metal impurities (Pb, Cd and Hg) and their potential impact on human health and the environment. The study highlights the advantages of using portable X-ray fluorescence (pXRF) analysis for rapid, non-destructive, and in situ analysis of heavy metals in jewelry. The results reveal that all products (n = 106) contained heavy metals at varying levels, Hg being the most commonly detected heavy metal. The fact that 71% of the samples exceeded the EU limit for Pb and 51% exceeded the EU limit for Cd is alarming and highlights the need for stricter regulations and monitoring of the jewelry industry to mitigate the risks posed by heavy metals in the environment. The study emphasizes the importance of using pXRF analysis to identify heavy metals in jewelry and address the literature gap in environmental risk assessments of Pb, Cd, and Hg in low-cost jewelry for adults from China. In general, the findings call for urgent action to ensure the safety of consumers and prevent environmental pollution by strengthening regulations and monitoring the jewelry industry.

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Forty-seven elements in leafy green vegetables were studied to estimate the daily intakes from this food category in different scenarios (average and high consumers) and age groups of the Canary Islands population. The contribution of the consumption of each type of vegetable to the reference intakes of essential, toxic and potentially toxic elements was assessed and the risk-benefit ratio was evaluated. The leafy vegetables that provide the highest levels of elements are spinach, arugula, watercress and chard. While spinach, chard, arugula, lettuce sprouts and watercress were the leafy vegetables with the highest concentrations of essential elements (38,743 ng/g of Fe in spinach, 3733 ng/g of Zn in watercress), the high levels of Mn in chard, spinach and watercress are noteworthy. Among the toxic elements, Cd is the element with the highest concentration, followed by As and Pb. The vegetable with the highest concentration of potentially toxic elements (Al, Ag, Be, Cr, Ni, Sr and V) is spinach. In average adult consumers, while the greatest contribution of essential elements comes from arugula, spinach and watercress, insignificant dietary intakes of potentially toxic metals are observed. Toxic metal intakes from the consumption of leafy vegetables in the Canary Islands do not show significant values, so the consumption of these foods does not pose a health risk. In conclusion, the consumption of leafy vegetables provides significant levels of some essential elements (Fe, Mn, Mo, Co and Se), but also of some potentially toxic elements (Al, Cr and Tl). A high consumer of leafy vegetables would see their daily nutritional needs regarding Fe, Mn, Mo, and Co covered, although they are also exposed to moderately worrying levels of Tl. To monitor the safety of dietary exposure to these metals, total diet studies on those elements with dietary exposures above the reference values derived from the consumption of this food category, mainly Tl, are recommended.

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Potential heavy metal impurities (HMI) in pharmaceuticals/pharmaceutical products/drugs based on plant raw materials (e.g., herbs) are an important problem in the pharmaceutical industry; however, there is a lack of scientific articles on the comprehensive toxicological risk assessment of HMI in ointment applied dermally. To make the appropriate toxicological risk assessment, we consider: (1) the raw results of the levels of lead and cadmium in the ointments (metal per kg of mass), (2) one-time administration of the applied ointment, (3) daily exposure of Pb and Cd in the applied ointments according to the maximum daily dose of applied pharmaceuticals, including transcutaneous penetration, (4) human health risk assessment based on the USEPA model, and 5) the margin of exposure (MoE). The raw results indicated that lead (7.05-101.78 µg/kg) and cadmium (0.32-0.81 µg/kg) were present in all samples. The levels of analyzed HMI (independently of the producer and declared composition) were similar. Pb and Cd contamination associated with daily doses met the standards of the ICH Q3D (R2) guide on elemental impurities in pharmaceuticals, including the cutaneous route of administration. Taking into account the daily amount of lead and cadmium (ointment, ug/day) the results were satisfactory, confirming the safety of marjoram herb extract ointments available in Polish pharmacies according to the ICH guideline Q3D (R2) on elemental impurities. The HQ values obtained for Pb and Cd in all samples were less than 1; therefore, exposure to these HMI would not cause a health risk based on the USEPA model strategy. Furthermore, the obtained values of MoE for Pb and Cd in ointments were above 100, so exposure to these elements would not cause a health risk based on the MoE-based strategy. The original contribution of this work is that this is the first study on the triple approach strategy to evaluate the safety of heavy metal impurities in traditional herbal medicinal products applied dermally in solid form (ointments with marjoram herb extract). The research is novel and has not been previously published; The proposed procedure includes transcutaneous penetration of heavy metal (Pb and Cd) impurities described for the first time in the literature.

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This paper reviews the impact of beer-making stages (malting, mashing, boiling, and fermentation) on the behavior of pesticide residues. The large use of pesticides on barley and hop could cause the occurrence of their residues in beer. The foremost factors influencing the stability of residues (pH, temperature, and water content) and the physical-chemical properties of pesticides (octanol-water partition coefficient, vapor pressure, and water solubility) are essential to know their final fate. Most pesticides show a decrease in the unhopped wort because they are adsorbed onto the spent grains after mashing. In addition, their concentrations decrease during boiling and fermentation. Generally, maltsters should dedicate particular attention to the residues of hydrophobic pesticides because they can remain on the malt. Contrarily, brewers should control residues of hydrophilic pesticides because they can be carried over into young beer, disturbing the quality and organoleptic properties (flavor, aroma, taste, or color) of the beer.

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Mint tea (Mentha piperita L.) is one of the most widely consumed single infusion herbal teas (infusion) around the world; however, impurities and pollutants can pose a potential health risk to human health during tea drinking. The idea of this study was the comprehensive toxicological risk assessment (TRA) of three heavy metals (As, Pb, and Cd) in mint tea infusions (Mentha piperita L.; n = 17) available in Polish markets. We applied an inductively coupled plasma mass spectrometry (ICP-MS)-based methodology for the determination of the chosen heavy metals and designed a specific TRA approach. The first step in our TRA was the determination of the elements investigated (heavy metal impurity profile, µg/L of infusion). The second step was the estimation of the weekly intake (µg/L of infusion/week) based on the weekly consumption of tea. The third step was the estimation of the weekly intake per body weight (µg/L of infusion/week/bw) based on the weekly consumption of tea per adult person compared to the Provisional Tolerable Weekly Intake (PTWI) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The level of investigated heavy metals occurs in all of the investigated mint tea infusions but at a relatively low level. The heavy metal profile indicated presence of As (0.36-1.254 µg/L), Pb (0.47-1.24 µg/L), and Cd (0.17-0.40 µg/L) in all the samples investigated. The basic analysis of the general content shows that As levels (mean = 0.70 µg/L) were very similar to the Pb levels (mean = 0.72 µg/L). The Cd content (mean = 0.21 µg/L) was approximately 3.5 times lower than the As and Pb levels. TRA provides satisfactory results for regulatory purposes. TRA for the elements investigated in the analyzed products indicated that there was no health hazard to consumers for weekly exposure. The results indicated that the levels of investigated elements in daily doses should not represent any health hazard to the consumer after drinking mini tea infusions from products available in Polish markets. This well-designed TRA methodology was useful and important for regulatory toxicology purposes.

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For decades, reclamation of pesticide contaminated sites has been a challenging avenue. Due to increasing agricultural demand, the application of synthetic pesticides could not be controlled in its usage, and it has now adversely impacted the soil, water, and associated ecosystems posing adverse effects on human health. Agricultural soil and pesticide manufacturing sites, in particular, are one of the most contaminated due to direct exposure. Among various strategies for soil reclamation, ecofriendly microbial bioremediation suffers inherent challenges for large scale field application as interaction of microbes with the polluted soil varies greatly under climatic conditions. Methodically, starting from functional or genomic screening, enrichment isolation; functional pathway mapping, production of tensioactive metabolites for increasing the bioavailability and bio-accessibility, employing genetic engineering strategies for modifications in existing catabolic genes to enhance the degradation activity; each step-in degradation study has challenges and prospects which can be addressed for successful application. The present review critically examines the methodical challenges addressing the feasibility for restoring and reclaiming pesticide contaminated sites along with the ecotoxicological risk assessments. Overall, it highlights the need to fine-tune the available processes and employ interdisciplinary approaches to make microbe assisted bioremediation as the method of choice for reclamation of pesticide contaminated sites.

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Traditional herbal medicinal products (THMP) with Plantago lanceolata L., folium (Ribwort Plantain Leaves) are well-known and very popular among the European population. The aim of our study was the toxicological risk assessment for adults of Pb impurities in THMP with Plantago lanceolata L. obtained from pharmacies in Poland. The estimations of Pb impurities in the single dose (22.1 - 50.7 ng/single dose) and in the daily dose (ng/day) were based on the worst-case scenario (WCS), i.e. based on the posology recommended by manufacturers. The estimated daily exposure (ng/day) meets the standards of the ICH Q3D (R1) guideline on elemental impurities (5.0 µg/day) according to the Pb levels (all results were below 250 ng/day). It can be concluded that all investigated THMPs with Plantago lanceolata L., folium available in pharmacies from Poland should not represent any health risk to the adults.