Nanotoxicology: an emerging discipline evolving from studies of ultrafine particles

Nanomedicine and voltage-gated sodium channel blockers in pain management: a game changer or a lost cause?

Pain, a complex and debilitating condition affecting millions globally, is a significant concern, especially in the context of post-operative recovery. This comprehensive review explores the complexity of pain and its global impact, emphasizing the modulation of voltage-gated sodium channels (VGSC or NaV channels) as a promising avenue for pain management with the aim of reducing reliance on opioids. The article delves into the role of specific NaV isoforms, particularly NaV 1.7, NaV 1.8, and NaV 1.9, in pain process and discusses the development of sodium channel blockers to target these isoforms precisely. Traditional local anesthetics and selective NaV isoform inhibitors, despite showing varying efficacy in pain management, face challenges in systemic distribution and potential side effects. The review highlights the potential of nanomedicine in improving the delivery of local anesthetics, toxins and selective NaV isoform inhibitors for a targeted and sustained release at the site of pain. This innovative strategy seeks to improve drug bioavailability, minimize systemic exposure, and optimize therapeutic outcomes, holding significant promise for secure pain management and enhancing the quality of life for individuals recovering from surgical procedures or suffering from chronic pain.

In vitro toxicity evaluation in A549 cells of diesel particulate matter from two different particle sampling systems and several resuspension media

In urban areas, inhalation of fine particles from combustion sources such as diesel engines causes adverse health effects. For toxicity testing, a substantial amount of particulate matter (PM) is needed. Conventional sampling involves collection of PM onto substrates by filtration or inertial impaction. A major drawback to those methodologies is that the extraction process can modify the collected particles and alter their chemical composition. Moreover, prior to toxicity testing, PM samples need to be resuspended, which can alter the PM sample even further. Lastly, the choice of the resuspension medium may also impact the detected toxicological responses. In this study, we compared the toxicity profile of PM obtained from two alternative sampling systems, using in vitro toxicity assays. One system makes use of condensational growth before collection in water in an impinger - BioSampler (CG-BioSampler), and the other, a Dekati® Gravimetric Impactor (DGI), is based on inertial impaction. In addition, various methods for resuspension of DGI collected PM were compared. Tested endpoints included cytotoxicity, formation of cellular reactive oxygen species, and genotoxicity. The alternative collection and suspension methods affected different toxicological endpoints. The water/dimethyl sulfoxide mixture and cell culture medium resuspended particles, along with the CG-BioSampler sample, produced the strongest responses. The water resuspended sample from the DGI appeared least toxic. CG-BioSampler collected PM caused a clear increased response in apoptotic cell death. We conclude that the CG-BioSampler PM sampler is a promising alternative to inertial impaction sampling.

Tuning the electronic properties of Zr UiO-66 through defect-functionalised multivariate modulation

The multivariate modulation of Metal-Organic Frameworks is presented as a valuable tool to introduce multiple functional units into UiO-66 while increasing its porosity. This manuscript encloses a comprehensive study using p-functionalised benzoate -NO2, -SO3 and -SH modulators, rationalizing the defects introduced and their impact on properties.

Chitosan hybrid nanomaterials: A study on interaction with biomimetic membranes

This study examined the influence of nanomaterials (NMs) on the organization of membrane lipids and the resulting morphological changes. The cell plasma membrane is heterogeneous, featuring specialized lipid domains in the liquid-ordered (Lo) phase surrounded by regions in the liquid-disordered (Ld) phase. We utilized model membranes composed of various lipids and lipid mixtures in different phase states to investigate the interactions between the NMs and membrane lipids. Specifically, we explored the interactions of pure chitosan (CS) and CS-modified nanocomposites (NCs) with ZnO, CuO, and SiO2 with four lipid mixtures: egg-phosphatidylcholine (EggPC), egg-sphingomyelin/cholesterol (EggSM/Chol), EggPC/Chol, and EggPC/EggSM/Chol, which represent the coexistence of Ld, Lo, and Ld/Lo, respectively. The data show that CS NMs increase the membrane lipid order (polarity) at glycerol level probed by Laurdan spectroscopy. Additionally, the interaction of CS-based NMs with membranes leads to an increase in bending elasticity modulus, zeta potential, and vesicle size. The lipid order changes are most significant in the highly fluid Ld phase, followed by the Lo/Ld coexistence phase, and are less pronounced in the tightly packed Lo phase. CS NMs induced egg PC vesicle adhesion, fusion, and shrinking. In heterogeneous Lo/Ld membranes, inward invaginations and vesicle shrinking via the Ld phase were observed. These findings highlight mechanisms involved in CS NM-lipid interactions in membranes that mimic plasma membrane heterogeneity.

Research progress on the pathogenesis and prediction of pneumoconiosis among coal miners

Pneumoconiosis is the most common occupational disease among coal miners, which is a lung disease caused by long-term inhalation of coal dust and retention in the lungs. The early stage of this disease is highly insidious, and pulmonary fibrosis may occur in the middle and late stages, leading to an increase in patient pain index and mortality rate. Currently, there is a lack of effective treatment methods. The pathogenesis of pneumoconiosis is complex and has many influencing factors. Although the characteristics of coal dust have been considered the main cause of different mechanisms of pneumoconiosis, the effects of coal dust composition, particle size and shape, and coal dust concentration on the pathogenesis of pneumoconiosis have not been systematically elucidated. Meanwhile, considering the irreversibility of pneumoconiosis progression, early prediction for pneumoconiosis patients is particularly important. However, there is no early prediction standard for pneumoconiosis among coal miners. This review summarizes the relevant research on the pathogenesis and prediction of pneumoconiosis in coal miners in recent years. Firstly, the pathogenesis of coal worker pneumoconiosis and silicosis was discussed, and the impact of coal dust characteristics on pneumoconiosis was analyzed. Then, the early diagnostic methods for pneumoconiosis have been systematically introduced, with a focus on image collaborative computer-aided diagnosis analysis and biomarker detection. Finally, the challenge of early screening technology for miners with pneumoconiosis was proposed.

The oxidative stress-dependent pulmonary inflammation of inhalable multi-walled carbon nanotube-containing nano-concrete dust and its comparison with conventional concrete dust and DQ12

Nano-concrete, which is an admixture of nanomaterials in concrete recipes, has been investigated to overcome the limitations of existing concrete, such as its stability and strength. However, there is no information on the human health effects of broken-down dust released during the construction and demolition efforts. In this study, we prepared an inhalable fraction of multi-walled carbon nanotube-containing nano-concrete dust and performed comparative toxicity studies with conventional concrete dust and DQ12 using a rat intratracheal instillation model. Although the recipes for concrete and nano-concrete are entirely different, the pulverized dust samples showed similar physicochemical properties, such as 0.46-0.48 µm diameter and chemical composition. Both concrete and nano-concrete dust exhibited similar patterns and magnitudes, representing acute neutrophilic inflammation and chronic active inflammation with lymphocyte infiltration. The toxicity endpoints of the tested particles at both time points showed an excellent correlation with the reactive oxygen species levels released from the alveolar macrophages, highlighting that alveolar macrophages are the primary target cells and that the oxidative stress paradigm is the main toxicity mechanism of the tested particles. In addition, the toxicity potentials of both concrete and nano-concrete dust were more than 10 times lower than that of DQ12.

Hazard assessment of hexagonal boron nitride and hexagonal boron nitride reinforced thermoplastic polyurethane composites using human skin and lung cells

Hexagonal boron nitride (hBN) is an emerging two-dimensional material attracting considerable attention in the industrial sector given its innovative physicochemical properties. Potential risks are associated mainly with occupational exposure where inhalation and skin contact are the most relevant exposure routes for workers. Here we aimed at characterizing the effects induced by composites of thermoplastic polyurethane (TPU) and hBN, using immortalized HaCaT skin keratinocytes and BEAS-2B bronchial epithelial cells. The composite was abraded using a Taber® rotary abraser and abraded TPU and TPU-hBN were also subjected to photo-Fenton-mediated degradation mimicking potential weathering across the product life cycle. Cells were exposed to the materials for 24 h (acute exposure) or twice per week for 4 weeks (chronic exposure) and evaluated with respect to material internalization, cytotoxicity, and proinflammatory cytokine secretion. Additionally, comprehensive mass spectrometry-based proteomics and metabolomics (secretomics) analyses were performed. Overall, despite evidence of cellular uptake of the material, no significant cellular and/or protein expression profiles alterations were observed after acute or chronic exposure of HaCaT or BEAS-2B cells, identifying only few pro-inflammatory proteins. Similar results were obtained for the degraded materials. These results support the determination of hazard profiles associated with cutaneous and pulmonary hBN-reinforced polymer composites exposure.

Concepts and Approaches to Reduce or Avoid Protein Corona Formation on Nanoparticles: Challenges and Opportunities

This review describes the formation of a protein corona (or its absence) on different classes of nanoparticles, its basic principles, and its consequences for nanomedicine. For this purpose, it describes general concepts to control (guide/minimize) the interaction between artificial nanoparticles and plasma proteins to reduce protein corona formation. Thereafter, methods for the qualitative or quantitative determination of protein corona formation are presented, as well as the properties of nanoparticle surfaces, which are relevant for protein corona prevention (or formation). Thereby especially the role of grafting density of hydrophilic polymers on the surface of the nanoparticle is discussed to prevent the formation of a protein corona. In this context also the potential of detergents (surfactants) for a temporary modification as well as grafting-to and grafting-from approaches for a permanent modification of the surface are discussed. The review concludes by highlighting several promising avenues. This includes (i) the use of nanoparticles without protein corona for active targeting, (ii) the use of synthetic nanoparticles without protein corona formation to address the immune system, (iii) the recollection of nanoparticles with a defined protein corona after in vivo application to sample the blood proteome and (iv) further concepts to reduce protein corona formation.

Ambient ultrafine particles exacerbate oxygen desaturation during sleep in patients with chronic obstructive pulmonary disease: New insights into the effect spectrum of ultrafine particles on susceptible populations

The health effects of ultrafine particles (UFPs) are of growing global concern, but the epidemiological evidence remains limited. Sleep-disordered breathing (SDB) characterized by hypoxemia is a prevalent condition linked to many debilitating chronic diseases. However, the role of UFPs in the development of SDB is lacking. Therefore, this prospective panel study was performed to specifically investigate the association of short-term exposure to UFPs with SDB parameters in patients with chronic obstructive pulmonary disease (COPD). Ninety-one COPD patients completed 226 clinical visits in Beijing, China. Personal exposure to ambient UFPs of 0-7 days was estimated based on infiltration factor and time-activity pattern. Real-time monitoring of sleep oxygen saturation, spirometry, respiratory questionnaires and airway inflammation detection were performed at each clinical visit. Generalized estimating equation was used to estimate the effects of UFPs. Exposure to UFPs was significantly associated with increased oxygen desaturation index (ODI) and percent of the time with oxygen saturation below 90 % (T90), with estimates of 21.50 % (95%CI: 6.38 %, 38.76 %) and 18.75 % (95%CI: 2.83 %, 37.14 %), respectively, per 3442 particles/cm3 increment of UFPs at lag 0-3 h. Particularly, UFPs' exposure within 0-7 days was positively associated with the concentration of alveolar nitric oxide (CaNO), and alveolar eosinophilic inflammation measured by CaNO exceeding 5 ppb was associated with 29.63 % and 33.48 % increases in ODI and T90, respectively. In addition, amplified effects on oxygen desaturation were observed in current smokers. Notably, individuals with better lung function and activity tolerance were more affected by ambient UFPs due to longer time spent outdoors. To our knowledge, this is the first study to link UFPs to hypoxemia during sleep and uncover the key role of alveolar eosinophilic inflammation. Our findings provide new insights into the effect spectrum of UFPs and potential environmental and behavioral intervention strategies to protect susceptible populations.

Transcriptome changes in humans acutely exposed to nanoparticles during grinding of dental nanocomposites

Aim: Today, there is a lack of research studies concerning human acute exposure to nanoparticles (NPs). Our investigation aimed to simulate real-world acute inhalation exposure to NPs released during work with dental nanocomposites in a dental office or technician laboratory. Methods: Blood samples from female volunteers were processed before and after inhalation exposure. Transcriptomic mRNA and miRNA expression changes were analyzed. Results: We detected large interindividual variability, 90 significantly deregulated mRNAs, and 4 miRNAs when samples of participants before and after dental nanocomposite grinding were compared. Conclusion: The results suggest that inhaled dental NPs may present an occupational hazard to human health, as indicated by the changes in the processes related to oxidative stress, synthesis of eicosanoids, and cell division.

In Vivo Exposure Pathways of Ambient Magnetite Nanoparticles Revealed by Machine Learning-Aided Single-Particle Mass Spectrometry

Nanosized ultrafine particles (UFPs) from natural and anthropogenic sources are widespread and pose serious health risks when inhaled by humans. However, tracing the inhaled UFPs in vivo is extremely difficult, and the distribution, translocation, and metabolism of UFPs remain unclear. Here, we report a label-free, machine learning-aided single-particle inductively coupled plasma mass spectrometry (spICP-MS) approach for tracing the exposure pathways of airborne magnetite nanoparticles (MNPs), including external emission sources, and distribution and translocation in vivo using a mouse model. Our results provide quantitative analysis of different metabolic pathways in mice exposed to MNPs, revealing that the spleen serves as the primary site for MNP metabolism (84.4%), followed by the liver (11.4%). The translocation of inhaled UFPs across different organs alters their particle size. This work provides novel insights into the in vivo fate of UFPs as well as a versatile and powerful platform for nanotoxicology and risk assessment.

Duo photoprotective effect via silica-coated zinc oxide nanoparticles and Vitamin C nanovesicles composites

OBJECTIVE

Zinc Oxide nanoparticles (ZnO NPs) are used widely in nowadays personal care products, especially sunscreens, as a protector against UV irradiation. Yet, they have some reports of potential toxicity. Silica is widely used to cage ZnO NPs to reduce their potential toxicity. Vitamin C derivative, Magnesium Ascorpyl Phosphate (MAP), is a potent antioxidant that can efficiently protect human skin from harmful impacts of UV irradiation and oxidative stress. The combination of silica coated ZnO NPs and MAP nanovesicles could have potential synergistic protective effect against skin photodamage.

METHODS

Silica coated ZnO NPs and MAP nanovesicles (ethosomes and niosomes) were synthesized, formulated, and evaluated as topical gels. These gel formulations were evaluated in mice for their photoprotective effect against UV irradiation through histopathology and immuno-histochemistry study. Split-face clinical study was conducted to compare the effect of application of silica coated ZnO NPs either alone or combined with MAP nanovesicles. Their photoprotective action was evaluated, using Antera 3D® camera, for melanin level, roughness index and wrinkles depth.

RESULTS

Silica coated ZnO NPs when combined with MAP nanovesicles protected mice skin from UV irradiation and decreased the expression of the proinflammatory cytokines, NF-κB. Clinically, silica coated ZnO NPs, alone or combined with MAP nanovesicles, could have significant effect to decrease melanin level, roughness index and wrinkles depth with higher effect for the combination.

CONCLUSION

A composite of silica coated ZnO NPs and MAP nanovesicles could be a promising cosmetic formulation for skin protection against photodamage signs such as hyperpigmentation, roughness, and wrinkles.

Worse pulmonary function in association with cumulative exposure to nanomaterials. Hints of a mediation effect via pulmonary inflammation

BACKGROUND

Today, nanomaterials are broadly used in a wide range of industrial applications. Such large utilization and the limited knowledge on to the possible health effects have raised concerns about potential consequences on human health and safety, beyond the environmental burden. Given that inhalation is the main exposure route, workers exposed to nanomaterials might be at risk of occurrence of respiratory morbidity and/or reduced pulmonary function. However, epidemiological evidence regarding the association between cumulative exposure to nanomaterials and respiratory health is still scarce. This study focused on the association between cumulative exposure to nanomaterials and pulmonary function among 136 workers enrolled in the framework of the European multicentric NanoExplore project.

RESULTS

Our findings suggest that, independently of lifelong tobacco smoking, ethnicity, age, sex, body mass index and physical activity habits, 10-year cumulative exposure to nanomaterials is associated to worse FEV1 and FEF25 - 75%, which might be consistent with the involvement of both large and small airway components and early signs of airflow obstruction. We further explored the hypothesis of a mediating effect via airway inflammation, assessed by interleukin (IL-)10, IL-1β and Tumor Necrosis Factor alpha (TNF-α), all quantified in the Exhaled Breath Condensate of workers. The mediation analysis results suggest that IL-10, TNF-α and their ratio (i.e., anti-pro inflammatory ratio) may fully mediate the negative association between cumulative exposure to nanomaterials and the FEV1/FVC ratio. This pattern was not observed for other pulmonary function parameters.

CONCLUSIONS

Safeguarding the respiratory health of workers exposed to nanomaterials should be of primary importance. The observed association between cumulative exposure to nanomaterials and worse pulmonary function parameters underscores the importance of implementing adequate protective measures in the nanocomposite sector. The mitigation of harmful exposures may ensure that workers can continue to contribute productively to their workplaces while preserving their respiratory health over time.

From Inhalation to Neurodegeneration: Air Pollution as a Modifiable Risk Factor for Alzheimer's Disease

Air pollution, a growing concern for public health, has been linked to various respiratory and cardiovascular diseases. Emerging evidence also suggests a link between exposure to air pollutants and neurodegenerative diseases, particularly Alzheimer's disease (AD). This review explores the composition and sources of air pollutants, including particulate matter, gases, persistent organic pollutants, and heavy metals. The pathophysiology of AD is briefly discussed, highlighting the role of beta-amyloid plaques, neurofibrillary tangles, and genetic factors. This article also examines how air pollutants reach the brain and exert their detrimental effects, delving into the neurotoxicity of air pollutants. The molecular mechanisms linking air pollution to neurodegeneration are explored in detail, focusing on oxidative stress, neuroinflammation, and protein aggregation. Preclinical studies, including in vitro experiments and animal models, provide evidence for the direct effects of pollutants on neuronal cells, glial cells, and the blood-brain barrier. Epidemiological studies have reported associations between exposure to air pollution and an increased risk of AD and cognitive decline. The growing body of evidence supporting air pollution as a modifiable risk factor for AD underscores the importance of considering environmental factors in the etiology and progression of neurodegenerative diseases, in the face of worsening global air quality.

Application of green synthesized Ag and Cu nanoparticles for the control of bruchids and their impact on seed quality and yield in greengram

Storage pests, particularly bruchids, are major biotic constraints causing significant storage losses in pulses. Conventional control methods relying on insecticides and fumigants often lead to food contamination due to toxic pesticide residues and a rapid decline in seed germination. In this investigation, through green nano-technological application, a promising and sustainable alternative for pest management is developed. Silver and copper nanoparticles were synthesized through ocimum leaf extract. The characterization of silver and copper nanoparticles was carried out by UV-spectroscopy, particle size analyzer, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared. Both the nanoparticles were spherical and crystalline in nature. Greengram seeds were primed with standardized silver and copper nanoparticles at different concentrations (1000, 1500, and 2000 ppm) and compared with castor-treated, deltamethrin-treated, and untreated control seeds for seed quality, growth, and yield. After one month of storage, all the pulse beetles released in different treatments exhibited 100 % mortality, whereas in control, the insects multiplied. At the end of nine months, the control seeds had shown 72 % damage and 39.67 % germination. In contrast, silver nanoparticles at 1000 ppm showed no seed damage and achieved 81.67 % germination, which was on par with copper nanoparticles at 1000 ppm with 79.33 % germination. Seed priming of silver and copper nanoparticles at 1000 ppm also demonstrated superior performance in all the seed quality and biochemical parameters (alpha amylase and catalase) throughout the storage period. Whereas, in the greenhouse experiment, enhanced growth (35.96 cm, 46.48 cm, and 53.00 cm at 30, 60 DAS, and at harvest, respectively) and yield per plant (3.75 g) were significantly higher in plants that were given foliar application with silver nanoparticles at 1000 ppm. Furthermore, foliar application of these nanoparticles at all concentrations (1000, 1500, and 2000 ppm) did not exhibit any adverse effects on soil microbial organisms, as assessed by dehydrogenase enzyme activity. Hence, this research highlights the potential use of silver and copper nanoparticles at 1000 ppm as effective tools for storage pest management and contributing to improved agricultural productivity and sustainability.

The effect of graphene oxide administration on the brains of male mice: Behavioral study and assessment of oxidative stress

Graphene oxide (GO) nanoparticles are attracting growing interest in various fields, not least because of their distinct characteristics and possible uses. However, concerns about their impact on neurological health are emerging, underlining the need for in-depth studies to assess their neurotoxicity. This study examines GO exposure's neurobehavioral and biochemical effects on the central nervous system (CNS). To this end, we administered two doses of GO (2 and 5 mg/kg GO) to mice over a 46-day treatment period. We performed a battery of behavioral tests on the mice, including the open field to assess locomotor activity, the maze plus to measure anxiety, the pole test to assess balance and the rotarod to measure motor coordination. In parallel, we analyzed malondialdehyde (MDA) levels and catalase activity in the brains of mice exposed to GO nanoparticles. In addition, X-ray energy dispersive (EDX) analysis was performed to determine the molecular composition of the brain. Our observations reveal brain alterations in mice exposed to GO by intraperitoneal injection, demonstrating a dose-dependent relationship. We identified behavioral alterations in mice exposed to GO, such as increased anxiety, decreased motor coordination, reduced locomotor activity and balance disorders. These changes were dose-dependent, suggesting a correlation between the amount of GO administered and the extent of behavioral alterations. At the same time, a dose-dependent increase in malondialdehyde and catalase activity was observed, reinforcing the correlation between exposure intensity and associated biochemical responses.

Probing wrapping dynamics of spherical nanoparticles by 3D vesicles using force-based simulations

Nanoparticles present in various environments can interact with living organisms, potentially leading to deleterious effects. Understanding how these nanoparticles interact with cell membranes is crucial for rational assessment of their impact on diverse biological processes. While previous research has explored particle-membrane interactions, the dynamic processes of particle wrapping by fluid vesicles remain incompletely understood. In this study, we introduce a force-based, continuum-scale model utilizing triangulated mesh representation and discrete differential geometry to investigate particle-vesicle interaction dynamics. Our model captures the transformation of vesicle shape and nanoparticle wrapping by calculating the forces arising from membrane bending energy and particle adhesion energy. Inspired by cell phagocytosis of large particles, we focus on establishing a quantitative understanding of large-scale vesicle deformation induced by the interaction with particles of comparable sizes. We first examine the interactions between spherical vesicles and individual nanospheres, both externally and internally, and quantify energy landscapes across different wrapping fractions of the nanoparticles. Furthermore, we explore multiple particle interactions with biologically relevant fluid vesicles with nonspherical shapes. Our study reveals that initial particle positions and interaction sequences are critical in determining the final equilibrium shapes of the vesicle-particle complexes in these interactions. These findings emphasize the importance of nanoparticle positioning and wrapping fractions in the dynamics of particle-vesicle interactions, providing crucial insights for future research in the field.

Characterization of the inhalable fraction (< 10 μm) of soil from highly urbanized and industrial environments: magnetic measurements, bioaccessibility, Pb isotopes and health risk assessment

Soil in urban and industrial areas is one of the main sinks of pollutants. It is well known that there is a strong link between metal(loid)s bioaccessibility by inhalation pathway and human health. The critical size fraction is < 10 μm (inhalable fraction) since these particles can approach to the tracheobronchial region. Here, soil samples (< 10 μm) from a highly urbanized area and an industrialized city were characterized by combining magnetic measurements, bioaccessibility of metal(loids) and Pb isotope analyses. Thermomagnetic analysis indicated that the main magnetic mineral is impure magnetite. In vitro inhalation analysis showed that Cd, Mn, Pb and Zn were the elements with the highest bioaccessibility rates (%) for both settings. Anthropogenic sources that are responsible for Pb accumulation in < 10 μm fraction are traffic emissions for the highly urbanized environment, and Pb related to steel emissions and coal combustion in cement plant for the industrial setting. We did not establish differences in the Pb isotope composition between pseudo-total and bioaccessible Pb. The health risk assessment via the inhalation pathway showed limited non-carcinogenic risks for adults and children. The calculated risks based on pseudo-total and lung bioaccessible concentrations were identical for the two areas of contrasting anthropogenic pressures. Carcinogenic risks were under the threshold levels (CR < 10-4), with Ni being the dominant contributor to risk. This research contributes valuable insights into the lung bioaccessibility of metal(loids) in urban and industrial soils, incorporating advanced analytical techniques and health risk assessments for a comprehensive understanding.

Smoking and pulmonary health in women: A narrative review and behavioral health perspective

OBJECTIVE

Cigarette smoking prevalence has declined slower among women than men, and smoking-related pulmonary disease (PD) has risen among women. Given these trends, there is a critical need to understand and mitigate PD risk among women who smoke. The purpose of this narrative review and commentary is to highlight important evidence from the literature on smoking and PD among women.

METHODS

This review focuses broadly on examining cigarette smoking and PD among women within six topic areas: (1) demographic characteristics and prevalence of smoking, (2) smoking behavior, (3) lung cancer, (4) obstructive PD, (5) diagnostic and treatment disparities, and (6) gaps in the literature and potential directions for future research and treatment.

RESULTS

Growing evidence indicates that compared to men, women are at increased risk for developing smoking-related PD and poorer PD outcomes. Gender disparities in smoking-related PD may be largely accounted for by genetic differences and sex hormones contributing to PD pathogenesis and presentation, smoking behavior, nicotine dependence, and pathogen/carcinogen clearance. Moreover, gender disparities in smoking-related PD may be exacerbated by important social determinants (e.g., women with less formal education and those from minoritized groups may be at especially high risk for poor PD outcomes due to higher rates of smoking).

CONCLUSION

Rising rates of smoking-related PD among women risk widening diagnostic and treatment disparities. Ongoing research is needed to explore potentially complex relationships between sex, gender, and smoking-related PD processes and outcomes, and to improve smoking-cessation and PD treatment for women.

Characterizing applications, exposure risks, and hazard communication for engineered nanomaterials in construction

BACKGROUND

Engineered nanomaterials (ENMs) may pose health risks to workers. Objectives were to characterize ENM applications in construction, identify exposure scenarios, and evaluate the quality of safety data sheets (SDSs) for nano-enabled construction products.

METHODS

SDSs and product data were obtained from a public database of nano-enabled construction products. Descriptive statistics were calculated for affected trades, product categories, and types of ENMs. A sample of SDSs (n = 33) was evaluated using modified criteria developed by NIOSH researchers. Bulk analysis via transmission electron microscopy characterized nanoparticles in a subset of products.

RESULTS

Companies report using >50 ENMs in construction products. ENM composition could not be determined via SDSs for 38.1% of the 907 products examined. Polymers and metal oxides tied for most frequently reported ENMs (n = 87, 9.6%). Nano silica, graphene, carbon nanotubes, and silver nanoparticles were also frequently reported. Most of the products were paints and coatings (n = 483, 53.3%), followed by pre-market additives, cementitious materials, insulation, and lubricants. Workers in twenty construction trades are likely to handle nano-enabled products, these particularly encompass cement and brick masons, painters, laborers, carpenters, glaziers, and insulators. A wide range of exposure scenarios were identified. SDSs were classified as satisfactory (18%), in need of improvement (12%), or in need of significant improvement (70%). Bulk analyses revealed discrepancies between actual ENM composition and those in SDSs.

DISCUSSION AND CONCLUSION

There has been significant progress investigating risks to construction workers posed by ENMs, but SDSs need major improvements. This study provides new insights on the use of ENMs in construction, exposure risks, and hazard communication.

Reproductive toxicity perspectives of nanoparticles: an update

INTRODUCTION

The rapid development of nanotechnologies with their widespread prosperities has advanced concerns regarding potential health hazards of the Nanoparticles.

RESULTS

Nanoparticles are currently present in several consumer products, including medications, food, textiles, sports equipment, and electrical components. Despite the advantages of Nanoparticles, their potential toxicity has negative impact on human health, particularly on reproductive health.

CONCLUSIONS

The impact of various NPs on reproductive system function is yet to be determined. Additional research is required to study the potential toxicity of various Nanoparticles on reproductive health. The primary objective of this review is to unravel the toxic effects of different Nanoparticles on the human reproductive functions and recent investigations on the reproductive toxicity of Nanoparticles both in vitro and in vivo.

The effects of iron oxide nanoparticles on antioxidant capacity and response to oxidative stress in Mozambique tilapia (Oreochromis mossambicus, Peters 1852)

Recent research has raised concern about the biocompatibility of iron oxide nanoparticles (IONPs), as they have been reported to induce oxidative stress and inflammatory responses, whilst prolonged exposure to high IONP concentrations may lead to cyto-/genotoxicity. Besides, there is concern about its environmental impact. The aim of our study was to investigate the effects of IONPs on the antioxidant defence system in freshwater fish Mozambique tilapia (Oreochromis mossambicus, Peters 1852). The fish were exposed to IONP concentration of 15 mg/L over 1, 3, 4, 15, 30, and 60 days and the findings compared to a control, unexposed group. In addition, we followed up the fish for 60 days after exposure had stopped to estimate the stability of oxidative stress induced by IONPs. Exposure affected the activity of antioxidant and marker enzymes and increased the levels of hydrogen peroxide and lipid peroxidation in the gill, liver, and brain tissues of the fish. Even after 60 days of depuration, adverse effects remained, indicating long-term nanotoxicity. Moreover, IONPs accumulated in the gill, liver, and brain tissues. Our findings underscore the potential health risks posed to non-target organisms in the environment, and it is imperative to establish appropriate guidelines for safe handling and disposal of IONPs to protect the aquatic environment.

Combining analytical techniques to assess the translocation of diesel particles across an alveolar tissue barrier in vitro

BACKGROUND

During inhalation, airborne particles such as particulate matter ≤ 2.5 μm (PM2.5), can deposit and accumulate on the alveolar epithelial tissue. In vivo studies have shown that fractions of PM2.5 can cross the alveolar epithelium to blood circulation, reaching secondary organs beyond the lungs. However, approaches to quantify the translocation of particles across the alveolar epithelium in vivo and in vitro are still not well established. In this study, methods to assess the translocation of standard diesel exhaust particles (DEPs) across permeable polyethylene terephthalate (PET) inserts at 0.4, 1, and 3 μm pore sizes were first optimized with transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-VIS), and lock-in thermography (LIT), which were then applied to study the translocation of DEPs across human alveolar epithelial type II (A549) cells. A549 cells that grew on the membrane (pore size: 3 μm) in inserts were exposed to DEPs at different concentrations from 0 to 80 µg.mL- 1 ( 0 to 44 µg.cm- 2) for 24 h. After exposure, the basal fraction was collected and then analyzed by combining qualitative (TEM) and quantitative (UV-VIS and LIT) techniques to assess the translocated fraction of the DEPs across the alveolar epithelium in vitro.

RESULTS

We could detect the translocated fraction of DEPs across the PET membranes with 3 μm pore sizes and without cells by TEM analysis, and determine the percentage of translocation at approximatively 37% by UV-VIS (LOD: 1.92 µg.mL- 1) and 75% by LIT (LOD: 0.20 µg.cm- 2). In the presence of cells, the percentage of DEPs translocation across the alveolar tissue was determined around 1% at 20 and 40 µg.mL- 1 (11 and 22 µg.cm- 2), and no particles were detected at higher and lower concentrations. Interestingly, simultaneous exposure of A549 cells to DEPs and EDTA can increase the translocation of DEPs in the basal fraction.

CONCLUSION

We propose a combination of analytical techniques to assess the translocation of DEPs across lung tissues. Our results reveal a low percentage of translocation of DEPs across alveolar epithelial tissue in vitro and they correspond to in vivo findings. The combination approach can be applied to any traffic-generated particles, thus enabling us to understand their involvement in public health.

Neurotoxicity of Some Environmental Pollutants to Zebrafish

The aquatic environment encompasses a wide variety of pollutants, from plastics to drug residues, pesticides, food compounds, and other food by-products, and improper disposal of waste is the main cause of the accumulation of toxic substances in water. Monitoring, assessing, and attempting to control the effects of contaminants in the aquatic environment are necessary and essential to protect the environment and thus human and animal health, and the study of aquatic ecotoxicology has become topical. In this respect, zebrafish are used as model organisms to study the bioaccumulation, toxicity, and influence of environmental pollutants due to their structural, functional, and material advantages. There are many similarities between the metabolism and physiological structures of zebrafish and humans, and the nervous system structure, blood-brain barrier function, and social behavior of zebrafish are characteristics that make them an ideal animal model for studying neurotoxicity. The aim of the study was to highlight the neurotoxicity of nanoplastics, microplastics, fipronil, deltamethrin, and rotenone and to highlight the main behavioral, histological, and oxidative status changes produced in zebrafish exposed to them.

Bioactivity of cerium dioxide nanoparticles as a function of size and surface features

Nano-dispersed cerium dioxide is promising for use in medicine due to its unique physicochemical properties, including low toxicity, the safety of in vivo usage, active participation in different redox processes occurring in living cells, and its regenerative potential, manifested in the ability of CeO2 to participate repeatedly in redox reactions. In this work, we examined the biological activity of cerium dioxide nanoparticles (CeO2 NPs) synthesized by precipitation in mixed water/alcohol solutions at a constant pH of 9. This synthesis method allowed controlling the size and Ce3+/Ce4+ proportion on the surface of NPs, changing the synthesis conditions and obtaining highly stable suspensions of "naked" CeO2 NPs. Changes in the surface properties upon contact of CeO2 NPs with protein-rich media, e.g., bovine serum albumin and DMEM cell culture medium supplemented with 10% fetal bovine serum, the characteristics of nanoparticle uptake by mouse aortic endothelial cells and the antioxidant activity of the nanoparticles of different sizes were investigated by various state-of-the-art analytical methods.

In vitro assessment of the effect of magnetic fields on efficacy of biosynthesized selenium nanoparticles by Alborzia kermanshahica

Cyanobacteria represent a rich resource of a wide array of unique bioactive compounds that are proving to be potent sources of anticancer drugs. Selenium nanoparticles (SeNPs) have shown an increasing potential as major therapeutic platforms and led to the production of higher levels of ROS that can present desirable anticancer properties. Chitosan-SeNPs have also presented antitumor properties against hepatic cancer cell lines, especially the Cht-NP (Chitosan-NPs), promoting ROS generation and mitochondria dysfunction. It is proposed that magnetic fields can add new dimensions to nanoparticle applications. Hence, in this study, the biosynthesis of SeNPs using Alborzia kermanshahica and chitosan (CS) as stabilizers has been developed. The SeNPs synthesis was performed at different cyanobacterial cultivation conditions, including control (without magnetic field) and magnetic fields of 30 mT and 60 mT. The SeNPs were characterized by uv-visible spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), Dynamic light scattering (DLS), zeta potential, and TEM. In addition, the antibacterial activity, inhibition of bacterial growth, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC), as well as the antifungal activity and cytotoxicity of SeNPs, were performed. The results of uv-visible spectrometry, DLS, and zeta potential showed that 60 mT had the highest value regarding the adsorption, size, and stabilization in compared to the control. FTIR spectroscopy results showed consistent spectra, but the increased intensity of peaks indicates an increase in bond number after exposure to 30 mT and 60 mT. The results of the antibacterial activity and the inhibition zone diameter of synthesized nanoparticles showed that Staphylococcus aureus was more sensitive to nanoparticles produced under 60 mT. Se-NPs produced by Alborzia kermanshahica cultured under a 60 mT magnetic field exhibit potent antimicrobial and anticancer properties, making them a promising natural agent for use in the pharmaceutical and biomedical industries.

Comet Assay and Micronucleus Test in Circulating Erythrocytes of Ctenopharyngodon idella Exposed to Nickel Oxide Nanoparticles

The number of pollutants released into freshwater and marine environments has increased due to the widespread use of nanoparticles. Nickel oxide nanoparticles (NiO-NPs) were tested for genotoxicity in fish fingerlings of the species Ctenopharyngodon idella. For 7, 14, and 21 days, fingerlings were exposed to NiO-NPs with each increasing concentrations of 2.25 mg/L, 4.50 mg/L, and 6.75 mg/L, respectively. The micronuclei assay and comet assay were used to evaluate the DNA damage. The experiment revealed that with the increase in nanoparticle concentration and exposure duration, the level of DNA damage also increased. The experiment resulted to be time and dose dependent, and the damage was found as follows: 6.75 mg/L > 4.50 mg/L > 2.25 mg/L against each exposure period. In terms of comet assay, the results showed that after 7 days, the level of DNA damage in all the concentrations was highly significant (P < 0.001). Increased DNA damage was calculated at the higher administered dose of 6.75 mg/L for 21 days of exposition, followed by 14 and 7 days, respectively. The second high toxic effect was observed in the fish blood at the exposure concentration of 4.50 mg/L for 21 days, followed by 14 and 7 days, respectively. The micronuclei induction in the nanoparticle's administered blood could be detected only for a 7-day exposition period. Whereas for the exposed duration of 14 and 21 days, the entire red blood cells of the grass carp were completely destroyed demonstrating the ability of the nanoparticles to cause anomalies in aquatic life.

Exposure to zinc oxide nanoparticles induced reproductive toxicities in male Sprague Dawley rats

BACKGROUND

This research delves into the reproductive toxicology of zinc oxide nanoparticles (ZnO-NPs) in male Sprague Dawley rats. It specifically examines the repercussions of Zn accumulation in the testes, alterations in testosterone levels, and histopathological changes in the gonadal tissues.

AIMS

The primary objective of this study is to elucidate the extent of reproductive toxicity induced by ZnO-NPs in male Sprague Dawley rats. The investigation aims to contribute to a deeper understanding of the potential endocrine and reproductive disruptions caused by ZnO-NPs exposure.

METHODS

Characterization techniques including SEM-EDX and XRD affirmed the characteristic nature of ZnO-NPs. Twenty-five healthy post weaning rats (200-250 g) were intraperitoneally exposed to different concentrations of ZnO-NPs @ 10 or 20 or 30 mg/kg BW for 28 days on alternate days.

RESULTS

Results showed significant dose dependent decline in the body weight and testicular somatic index of rats. It also showed significant dose dependent accumulation of Zn in testis with increasing dose of ZnO-NPs. Conversely, serum testosterone level and sperm count were reduced with increasing dose of ZnO-NPs. Histological results showed dose dependent abnormalities i.e., vacuolization, edema, hemorrhage, destruction of seminiferous tubules, loss of germ cells and necrosis in rat testis.

CONCLUSION

The findings of this study clearly indicate that high doses of zinc oxide nanoparticles (ZnO-NPs) can adversely affect the structural integrity and functional efficacy of the male reproductive system. Given these results, it becomes crucial to implement stringent precautionary measures in the utilization of ZnO-NPs, particularly in cosmetics and other relevant sectors. Such measures are imperative to mitigate the toxicological impact of ZnO-NPs on the male reproductive system and potentially on other related physiological functions. This study underscores the need for regulatory vigilance and safety assessments in the application of nanotechnology to safeguard human health.

Reducing Transmission of Airborne Respiratory Pathogens: A New Beginning as the COVID-19 Emergency Ends

BACKGROUND

In response to the COVID-19 pandemic, new evidence-based strategies have emerged for reducing transmission of respiratory infections through management of indoor air.

OBJECTIVES

This paper reviews critical advances that could reduce the burden of disease from inhaled pathogens and describes challenges in their implementation.

DISCUSSION

Proven strategies include assuring sufficient ventilation, air cleaning by filtration, and air disinfection by germicidal ultraviolet (UV) light. Layered intervention strategies are needed to maximize risk reduction. Case studies demonstrate how to implement these tools while also revealing barriers to implementation. Future needs include standards designed with infection resilience and equity in mind, buildings optimized for infection resilience among other drivers, new approaches and technologies to improve ventilation, scientific consensus on the amount of ventilation needed to achieve a desired level of risk, methods for evaluating new air-cleaning technologies, studies of their long-term health effects, workforce training on ventilation systems, easier access to federal funds, demonstration projects in schools, and communication with the public about the importance of indoor air quality and actions people can take to improve it. https://doi.org/10.1289/EHP13878.

Maternal occupational exposure to carbonaceous nanoscale particles and neurodevelopmental outcomes in early childhood: Analysis of the French Longitudinal Study of Children - Elfe study

OBJECTIVE

To investigate the association between occupational exposures to carbonaceous unintentionally emitted nanoscale particles (UNPs) during pregnancy and the child's language development and behaviour at two years old.

METHODS

Using data from the French Longitudinal Study of Childhood - ELFE, we selected mothers who worked during pregnancy and their children. Exposure to carbonaceous UNPs was assessed by the MatPUF (job-exposure matrix for ultrafine particles). Children's lexical development was analysed using 'the Mac Arthur - Bates communicative development inventories-words and sentences-short form' (MB-CDI) in a multivariate binary logistic regression. Their risk for autism spectrum disorders was studied using 'the Modified-CHecklist for Autism in Toddler' (M-CHAT) according to the recommended thresholds (low risk = 0-2; intermediate risk = 3-6 and high risk = 7-23) in unordered multinomial logistic regression models.

RESULTS

Maternal occupational exposure to carbonaceous UNPs was associated with delayed child language development (ORadj: 1.34; 95 % CI: 1.00, 1.80) but not with behavioural disorders (autism spectrum disorders) at two years old.

CONCLUSION

This is the first epidemiological study to show a significant association between maternal occupational exposure to carbonaceous nanoscale particles and child language development at 2 years old.

Determination of the Nanoscale Silica Mass Fraction by AF4/ICP-MS with Isotope Dilution Analysis Using 29Si-Enriched Silica Nanoparticles

A methodology based on the use of asymmetrical flow field-flow fractionation (AF4) coupled to ICP-MS with size fraction-targeted isotope dilution analysis (IDA) has been developed, validated, and applied for the first time to determine the mass fraction of nanoscale silica (SiO2). For this purpose, 29Si-enriched SiO2 nanoparticles, to be used as an IDA spike/internal standard, were synthesized and characterized in-house. Double IDA was used to quantify an aqueous suspension of Stöber silica particles of similar characteristics to those of the 29SiO2 nanoparticle (NP) spike using a representative test material of natural Si isotopic composition as the calibrant. For fumed SiO2 NP in a highly complex food matrix, a methodology based on single IDA with AF4/ICP-MS using the same 29SiO2 NP spike was developed and validated. Relative expanded measurement uncertainties (k = 2) of 4% (double IDA) and 8% (single IDA) were achieved for nanoscale silica mass fractions of 5143 and 107 mg kg-1 in water suspension and food matrix, respectively. To assess the accuracy of AF4/ICP-IDMS for the characterization of SiO2 NP in a food matrix, standard addition measurements on samples spiked with Aerosil AF200, also in-house characterized for Si mass fraction, were undertaken, with an average recovery of 95.6 ± 4.1% (RSD, n = 3) obtained. The particle-specific IDA data obtained for both SiO2 NP-containing samples were also compared with that of post-AF4 channel external calibration using inorganic Si standards. The mass fractions obtained by IDA agreed well with those obtained by external calibration within their associated measurement uncertainties.

Molecular mechanism of nanomaterials induced liver injury: A review

The unique physicochemical properties inherent to nanoscale materials have unveiled numerous potential applications, spanning beyond the pharmaceutical and medical sectors into various consumer industries like food and cosmetics. Consequently, humans encounter nanomaterials through diverse exposure routes, giving rise to potential health considerations. Noteworthy among these materials are silica and specific metallic nanoparticles, extensively utilized in consumer products, which have garnered substantial attention due to their propensity to accumulate and induce adverse effects in the liver. This review paper aims to provide an exhaustive examination of the molecular mechanisms underpinning nanomaterial-induced hepatotoxicity, drawing insights from both in vitro and in vivo studies. Primarily, the most frequently observed manifestations of toxicity following the exposure of cells or animal models to various nanomaterials involve the initiation of oxidative stress and inflammation. Additionally, we delve into the existing in vitro models employed for evaluating the hepatotoxic effects of nanomaterials, emphasizing the persistent endeavors to advance and bolster the reliability of these models for nanotoxicology research.

A Systematic Genotoxicity Assessment of a Suite of Metal Oxide Nanoparticles Reveals Their DNA Damaging and Clastogenic Potential

Metal oxide nanoparticles (MONP/s) induce DNA damage, which is influenced by their physicochemical properties. In this study, the high-throughput CometChip and micronucleus (MicroFlow) assays were used to investigate DNA and chromosomal damage in mouse lung epithelial cells induced by nano and bulk sizes of zinc oxide, copper oxide, manganese oxide, nickel oxide, aluminum oxide, cerium oxide, titanium dioxide, and iron oxide. Ionic forms of MONPs were also included. The study evaluated the impact of solubility, surface coating, and particle size on response. Correlation analysis showed that solubility in the cell culture medium was positively associated with response in both assays, with the nano form showing the same or higher response than larger particles. A subtle reduction in DNA damage response was observed post-exposure to some surface-coated MONPs. The observed difference in genotoxicity highlighted the mechanistic differences in the MONP-induced response, possibly influenced by both particle stability and chemical composition. The results highlight that combinations of properties influence response to MONPs and that solubility alone, while playing an important role, is not enough to explain the observed toxicity. The results have implications on the potential application of read-across strategies in support of human health risk assessment of MONPs.

High-Throughput Silica Nanoparticle Detection for Quality Control of Complex Early Life Nutrition Food Matrices

The addition of nanomaterials to improve product properties has become a matter of course for many commodities: e.g., detergents, cosmetics, and food products. While this practice improves product characteristics, the increasing exposure and potential impact of nanomaterials (<100 nm) raise concerns regarding both the human body and the environment. Special attention should be taken for vulnerable individuals such as those who are ill, elder, or newborns. But detecting and quantifying nanoparticles in complex food matrices like early life nutrition (ELN) poses a significant challenge due to the presence of additional particles, emulsion-droplets, or micelles. There is a pressing demand for standardized protocols for nanoparticle quantification and the specification of "nanoparticle-free" formulations. To address this, silica nanoparticles (SiNPs), commonly used as anticaking agents (AA) in processed food, were employed as a model system to establish characterization methods with different levels of accuracy and sensitivity versus speed, sample handling, and automatization. Different acid treatments were applied for sample digestion, followed by size exclusion chromatography. Morphology, size, and number of NPs were measured by transmission electron microscopy, and the amount of Si was determined by microwave plasma atomic emission spectrometry. This successfully enabled distinguishing SiNP content in ELN food formulations with 2-4% AA from AA-free formulations and sorting SiNPs with diameters of 20, 50, and 80 nm. Moreover, the study revealed the significant influence of the ELN matrix on sample preparation, separation, and characterization steps, necessitating method adaptations compared to the reference (SiNP in water). In the future, we expect these methods to be implemented in standard quality control of formulation processes, which demand high-throughput analysis and automated evaluation.

Biological effects of molybdenum(IV) sulfide nanoparticles and microparticles in the rat after repeated intratracheal administration

In this study, molybdenum(IV) sulfide (MoS2 ) nanoparticles (97 ± 32 nm) and microparticles (1.92 ± 0.64 μm) stabilized with poly (vinylpolypyrrolidone) (PVP) were administered intratracheally to male and female rats (dose of 1.5 or 5 mg/kg bw), every 14 days for 90 days (seven administrations in total). Blood parameters were assessed during and at the end of the study (hematology, biochemistry including glucose, albumins, uric acid, urea, high density lipoprotein HDL, total cholesterol, triglycerides, aspartate transaminase, and alanine transaminase ALT). Bronchoalveolar lavage fluid (BALF) analyses included cell viability, biochemistry (total protein concentration, lactate dehydrogenase, and glutathione peroxidase activity), and cytokine levels (tumor necrosis factor α, TNF-α, macrophage inflammatory protein 2-alpha, MIP-2, and cytokine-induced neutrophil chemoattractant-2, CINC-2). Tissues were subjected to routine histopathological and electron microscopy (STEM) examinations. No overt signs of chronic toxicity were observed. Differential cell counts in BALF revealed no significant differences between the animal groups. An increase in MIP-2 and a decrease in TNF-α were observed in BALF in the exposed males. The histopathological changes in the lung evaluated according to a developed classification system (based on severity of inflammation, range 0-4, with 4 indicating the most severe changes) showed average histopathological score of 1.33 for animals exposed to nanoparticles and microparticles at the lower dose, 1.72 after exposure to nanoparticles at the higher dose, and 2.83 for animals exposed to microparticles at the higher dose. In summary, it was shown that nanosized and microsized MoS2 can trigger dose-dependent inflammatory reactions in the lungs of rats after multiple intratracheal instillation irrespective of the animal sex. Some evidence indicates a higher lung pro-inflammatory potential of the microform.

Exploring the potential and challenges of developing physiologically-based toxicokinetic models to support human health risk assessment of microplastic and nanoplastic particles

Microplastics (MPs) and nanoplastics (NPs) pollution has emerged as a significant and widespread environmental issue. Humans are inevitably exposed to MPs and NPs via ingestion, inhalation, and dermal contacts from various sources. However, mechanistic knowledge of their distribution, interaction, and potency in the body is still lacking. To address this knowledge gap, we have undertaken the task of elucidating the toxicokinetic (TK) behaviors of MPs and NPs, aiming to provide mechanistic information for constructing a conceptual physiologically based toxicokinetic (PBTK) model to support in silico modeling approaches. Our effort involved a thorough examination of the existing literature and data collation on the presence of MPs in the human body and in vitro/ex vivo/in vivo biodistribution across various cells and tissues. By comprehending the absorption, distribution, metabolism, and excretion mechanisms of MPs and NPs in relation to their physicochemical attributes, we established a foundational understanding of the link between external exposure and internal tissue dosimetry. We observed that particle size and surface chemistry have been thoroughly explored in previous experimental studies. However, certain attributes, such as polymer type, shape, and biofilm/biocorona, warrant attention and further examination. We discussed the fundamental disparities in TK properties of MPs/NPs from those of engineered nanoparticles. We proposed a preliminary PBTK framework with several possible modeling approaches and discussed existing challenges for further investigation. Overall, this article provides a comprehensive compilation of existing TK data of MPs/NPs, a critical overview of TK processes and mechanisms, and proposes potential PBTK modeling approaches, particularly regarding their applicability to the human system, and outlines future perspectives for developing PBTK models and their integration into human health risk assessment of MPs and NPs.

Particulate iron oxide food colorants (E 172) during artificial digestion and their uptake and impact on intestinal cells

Iron oxide of various structures is frequently used as food colorant (E 172). The spectrum of colors ranges from yellow over orange, red, and brown to black, depending on the chemical structure of the material. E 172 is mostly sold as solid powder. Recent studies have demonstrated the presence of nanoscaled particles in E 172 samples, often to a very high extent. This makes it necessary to investigate the fate of these particles after oral uptake. In this study, 7 differently structured commercially available E 172 food colorants (2 x Yellow FeO(OH), 2 x Red Fe2O3, 1 x Orange Fe2O3 + FeO(OH) and 2 x Black Fe3O4) were investigated for particle dissolution, ion release, cellular uptake, crossing of the intestinal barrier and toxicological impact on intestinal cells. Dissolution was analyzed in water, cell culture medium and artificial digestion fluids. Small-angle X-ray scattering (SAXS) was employed for determination of the specific surface area of the colorants in the digestion fluids. Cellular uptake, transport and toxicological effects were studied using human differentiated Caco-2 cells as an in vitro model of the intestinal barrier. For all materials, a strong interaction with the intestinal cells was observed, albeit there was only a limited dissolution, and no toxic in vitro effects on human cells were recorded.

Ecotoxicological Properties of Pure and Phosphorus-Containing Graphene Oxide Bidimensional Sheets in Daphnia magna

In this work, the synthesis and structural, thermal, vibrational, morphological, and electronic characterization of 2D-like pure graphene oxide (GO) and phosphorus-containing graphene oxide (GOP) sheets were investigated. The average thicknesses of GO and GOP were 0.8 μm and 3.1 μm, respectively. The electron energy-loss spectroscopy spectra were used to analyze the differences in the C-K and O-K energy edge bands between GO and GOP. In addition, colloidal stability was studied using dynamic light scattering and zeta potential physicochemical techniques, determining that as the concentration increases, the hydrodynamic diameter and electrostatic stability of GO and GOP increase. The colloidal stability was quite important to ensure the interaction between the suspended solid phase and the biomarker. The 2D-like materials were used to determine their ecotoxicological properties, such as the medium lethal concentration, a crucial parameter for understanding ecotoxicity. Acute ecotoxicity experiments (24 h) were conducted in triplicate to obtain robust statistics, with corresponding mean lethal concentration (LC50) of 11.4 mg L-1 and 9.8 mg L-1 for GO and GOP, respectively. The morphological parameters of GO and GOP were compared with a negative control. However, only the case of GO was analyzed, since the Daphnia magna (D. magna) set exposed to GOP died before completing the time required for morphological analysis. The results indicate that the GOP sample is more toxic than the GO, both during and after exposure. Furthermore, the morphological parameters with the greatest statistically significant changes (p<0.05) were associated with the heart and body, while the eye and tail showed less significant changes.

Impacts of the aerosol mixing state and new particle formation on CCN in summer at the summit of Mount Tai (1534m) in Central East China

In this study, the aerosol size distributions, cloud condensation nuclei (CCN) number concentration (NCCN), single-particle chemical composition and meteorological data were collected from May 12 to June 8, 2017, at the summit of Mt. Tai. The effects of new particle formation (NPF) events and aerosol chemical components on CCN at Mt. Tai were analyzed in detail. The results showed that, NPF events significantly enhanced the CCN population, and the enhancement effect increased with increasing supersaturation (SS) value at Mt.Tai. NCCN at SS ranging from 0.1 to 0.9 % on NPF days was 10.9 %, 36.5 %, 44.6 %, 53.5 % and 51.5 % higher than that on non-NPF days from 10:00-13:00 as NPF events progressed. The effect of chemical components on CCN activation under the influence of NPF events was greater than that in the absence of NPF events. The correlation coefficients of EC-Nitrate particles (EC-Sulfate particles) and CCN at all SS levels on NPF days were 1.31-1.59 times (1.17-1.35 times) higher than those on non-NPF days. Nitrate particles promoted CCN activation but sulfate particles inhibited activation at Mt. Tai. There are differences or even opposite effects of the same group of particles on CCN activation under the influence of NPF events in different air masses. EC-Sulfate particles inhibited CCN activation at all SS levels for type I but weakly promoted activation at lower SS ranging from 0.1 to 0.3 % and weakly inhibited it at higher 0.9 % SS for type II. OCEC particles significantly inhibited CCN activation for type II, and this effect decreased with increasing SS. OCEC particles only weakly inhibited activation at SS ranging from 0.5 to 0.7 % for type I. OCEC particles only weakly inhibited this process at 0.1 % SS, while they very weakly promoted activation for SS > 0.1 %. This reveals that the CCN activity is not only related to the chemical composition of the particles, but the mixing state also has an important effect on the CCN activity.

State of the Art of Silica Nanoparticles: An Overview on Biodistribution and Preclinical Toxicity Studies

Over the past few years, nanoparticles have drawn particular attention in designing and developing drug delivery systems due to their distinctive advantages like improved pharmacokinetics, reduced toxicity, and specificity. Along with other successful nanosystems, silica nanoparticles (SNPs) have shown promising effects for therapeutic and diagnostic purposes. These nanoparticles are of great significance owing to their modifiable surface with various ligands, tunable particle size, and large surface area. The rate and extent of degradation and clearance of SNPs depend on factors such as size, shape, porosity, and surface modification, which directly lead to varying toxic mechanisms. Despite SNPs' enormous potential for clinical and pharmaceutical applications, safety concerns have hindered their translation into the clinic. This review discusses the biodistribution, toxicity, and clearance of SNPs and the formulation-related factors that ultimately influence clinical efficacy and safety for treatment. A holistic view of SNP safety will be beneficial for developing an enabling SNP-based drug product.

Source apportionment of fine and ultrafine particle number concentrations in a major city of the Eastern Mediterranean

Ultrafine particles (UFP) are recognized as an emerging pollutant able to induce serious health effects. However, quantitative information regarding the contributions of UFP sources is generally limited. This study evaluates statistical (k-means clustering) and receptor models (Positive Matrix Factorization - PMF) using particle number size distributions (PNSD), along with chemical speciation data, measured at an urban background supersite in Athens, Greece, aiming to characterize their sources. PNSD measurements (10-487 nm) were performed during three distinct periods (warm, cold, and lockdown cold). Traffic and residential biomass burning (BB) produced high UFP number concentrations (NUFP) in the cold period (+107 % compared to summer), while the lockdown restrictions reduced NUFP (-42 %). The five groups produced by cluster analysis that were common among periods were linked to high- and low-traffic, new particle formation (NPF), urban background and regional aerosols. PMF source apportionment identified 5 and 6 factors during warm and cold periods, respectively, indicating that traffic particles dominated NUFP (64-78 % in all periods), while accumulation-mode particles and volume concentrations were controlled by processed aerosol, and especially in the cold periods by BB emissions. A nucleation factor linked to NPF contributed 7-11 % to NUFP. Comparing the two cold periods (business-as-usual, lockdown), important lockdown reductions (-46 %) were seen for fresh traffic contributions to total number concentration (Ntotal). The impact of the source attributed to NPF also eroded (-41 % for Ntotal). Due to the large reduction (-47 % for Ntotal) observed also for the BB source during the lockdown (reduced wood usage due to a milder winter), the relative contributions of all sources did not change considerably (fractional reductions <7 % for Ntotal). The quantitative results, bolstered by source apportionment combining PNSD and online chemical composition measurements, indicate the potential to constrain UFP levels by regulating traffic and residential emissions, with a large upside for population exposure control.

Microplastic-induced inhibition of cell adhesion and toxicity evaluation using human dermal fibroblast-derived spheroids

Nanoplastics and microplastics (MPs) can significantly affect marine ecosystems and pose potential risks to human health. Although adverse effects stemming from direct exposure to MPs have been demonstrated at the cellular level in animal models, the potential toxicity of these materials in the human body remains uncertain. In this study, we investigated the three-dimensional (3D) behavior of dermal-derived cells exposed to MPs using artificially manufactured spherical primary polystyrene (PS) particles. To explore these effects, we used cellular spheroids as a 3D cell culture model, examined the size-dependent penetration of PS-MPs, and observed morphological alterations in the spheroids. Furthermore, we assessed changes in physiological activities, including reactive oxygen species, adenosine triphosphate, and lactate dehydrogenase, to elucidate the potential intra- and extracellular toxic reactions to PS-MPs. Additionally, our examination of cell-cell junctions and the extracellular matrix (ECM), along with analysis of the regulators involved in their decreased integrity, revealed negatively influenced changes in expression. This exposure study using spheroid models provides new insights into the potential toxicity of short-term exposure to MPs under conditions that closely resemble in vivo systems.

Reduced toxic effects of nano‑copper sulfate in comparison of bulk CuSO4 on biochemical parameters in the Rohu (Labeo rohita)

Considering the wide application of nanoparticles in various fields of life and growing concern regarding their toxic effects, the present study was designed with the aim to evaluate the potential risks of using copper sulfate nanoparticles (CuSO4-NPs) in comparison to bulk form. Nanoparticles of CuSO4, having mean size of 73 nm were prepared by ball milling method, and fingerlings of Labeo rohita were exposed to two levels, 20 and 100 μg L-1 of CuSO4 in both bulk and nano forms for 28 days and their comparative effects on the metallothioneins (MTs), heat shock proteins 70 (HSP 70), lipid profile, cholesterol (CHOL) and triglyceraldehyde (TG) levels, activities of some metabolic enzymes Alanine transaminase (ALT), Aspartate transaminase (AST) Akaline phosphatase (ALP), and genes expressions of HSP-70, TNF-α and IL1-ß were investigated. CuSO4 showed the concentration and particle type dependent effects. The over expression of HSPs and MTs, significant decreases in CHOL, TG, low density lipid (LDL) levels and ALP activity, while significant increases in high density lipid (HDL)level as well as ALT and AST activities and HSP-70, TNF-α and IL1-β expressions were observed in response to higher concentration of both bulk and nano form of copper sulfate. At lower concentration (20 μg L-1), however, only bulk form showed toxicity. Thus, low concentrations of CuSO4-NPs pose negligible threat to freshwater fish.

Assessment of emissions and exposure in 3D printing workplaces in Taiwan

Three-dimensional (3D) printing is an emerging and booming industry in Taiwan. Compared to traditional manufacturing, 3D printing has various advantages, such as advanced customization, additive manufacturing, reduced mold opening time, and reduced consumption of precursors. In this study, the real-time monitoring of particulate matter (PM) and total volatile organic compound (TVOC) emissions from various filaments is investigated using fused deposition modeling with material extrusion technology, a liquid-crystal display, a stereolithography apparatus based on vat photopolymerization technology, and binder jetting for occupational settings. An exposure assessment for nearby workers using the 3D printing process was performed, and improvement measures were recommended. Nine 3D printing fields were measured. The generation rate of ultrafine particles ranged from 1.19 × 1010 to 4.90 × 1012 #/min, and the geometric mean particle size ranged from 30.91 to 55.50 nm. The average concentration of ultrafine particles ranged from 2.31 × 103 to 7.36 × 104 #/cm3, and the PM2.5 and PM10 concentrations in each field ranged from 0.74 ± 0.27 to 12.46 ± 5.61 μg/m3 and from 2.39 ± 0.60 to 30.65 ± 21.26 μg/m3, respectively. The TVOC concentration ranged from 0.127 ± 0.012 to 1.567 ± 0.172 ppm. The respiratory deposition (RDUFPs) dose ranged from 2.02 × 1013 to 5.54 × 1014 nm2/day. Depending on the operating conditions, appropriate control and protective measures should be employed to protect workers' health.

The use of a complex tetra-culture alveolar model to study the biological effects induced by gold nanoparticles with different physicochemical properties

A substantial increase in engineered nanoparticles in consumer products has been observed, heightening human and environmental exposure. Inhalation represents the primary route of human exposure, necessitating a focus on lung toxicity studies. However, to avoid ethical concerns the use of in vitro models is an efficient alternative to in vivo models. This study utilized an in vitro human alveolar barrier model at air-liquid-interface with four cell lines, for evaluating the biological effects of different gold nanoparticles. Exposure to PEGylated gold nanospheres, nanorods, and nanostars did not significantly impact viability after 24 h, yet all AuNPs induced cytotoxicity in the form of membrane integrity impairment. Gold quantification revealed cellular uptake and transport. Transcriptomic analysis identified gene expression changes, particularly related to the enhancement of immune cells. Despite limited impact, distinct effects were observed, emphasizing the influence of nanoparticles physicochemical parameters while demonstrating the model's efficacy in investigating particle biological effects.

Inter-annual trends of ultrafine particles in urban Europe

Ultrafine particles (UFP, those with diameters ≤ 100 nm), have been reported to potentially penetrate deeply into the respiratory system, translocate through the alveoli, and affect various organs, potentially correlating with increased mortality. The aim of this study is to assess long-term trends (5-11 years) in mostly urban UFP concentrations based on measurements of particle number size distributions (PNSD). Additionally, concentrations of other pollutants and meteorological variables were evaluated to support the interpretations. PNSD datasets from 12 urban background (UB), 5 traffic (TR), 3 suburban background (SUB) and 1 regional background (RB) sites in 15 European cities and 1 in the USA were evaluated. The non-parametric Theil-Sen's method was used to detect monotonic trends. Meta-analyses were carried out to assess the overall trends and those for different environments. The results showed significant decreases in NO, NO2, BC, CO, and particle concentrations in the Aitken (25-100 nm) and the Accumulation (100-800 nm) modes, suggesting a positive impact of the implementation of EURO 5/V and 6/VI vehicle standards on European air quality. The growing use of Diesel Particle Filters (DPFs) might also have clearly reduced exhaust emissions of BC, PM, and the Aitken and Accumulation mode particles. However, as reported by prior studies, there remains an issue of poor control of Nucleation mode particles (smaller than 25 nm), which are not fully reduced with current DPFs, without emission controls for semi-volatile organic compounds, and might have different origins than road traffic. Thus, contrasting trends for Nucleation mode particles were obtained across the cities studied. This mode also affected the UFP and total PNC trends because of the high proportion of Nucleation mode particles in both concentration ranges. It was also found that the urban temperature increasing trends might have also influenced those of PNC, Nucleation and Aitken modes.

Multipollutant reciprocal neurological hazard from smoke particulate matter and heavy metals cadmium and lead in brain nerve terminals

Heavy metals, Cd2+ and Pb2+, and carbonaceous air pollution particulate matter are hazardous neurotoxicants. Here, a capability of water-suspended smoke particulate matter preparations obtained from poplar wood (WPs) and polypropylene fibers (medical facemasks) (MPs) to influence Cd2+/Pb2+-induced neurotoxicity, and vice versa, was monitored using biological system, i.e. isolated presynaptic rat cortex nerve terminals. Combined application of Pb2+ and WPs/MPs to nerve terminals in an acute manner revealed that smoke preparations did not change a Pb2+-induced increase in the extracellular levels of excitatory neurotransmitter L-[14C]glutamate and inhibitory one [3H]GABA, thereby demonstrating additive result and no interference of neurotoxic effects of Pb2+ and particulate matter. Whereas, both smoke preparations decreased a Cd2+-induced increase in the extracellular level of L-[14C]glutamate and [3H]GABA in nerve terminals. In fluorimetric measurements, the metals and smoke preparations demonstrated additive effects on the membrane potential of nerve terminals causing membrane depolarisation. WPs/MPs-induced reduction of spontaneous ROS generation was mitigated by Cd2+ and Pb2+. Therefore, a potential variety of multipollutant heavy metal-/airborne particulate-induced effects on key presynaptic processes was revealed. Multipollutant reciprocal neurological hazard through disturbance of the excitation-inhibition balance, membrane potential and ROS generation was evidenced. This multipollutant approach and data contribute to up-to-date environmental quality/health risk estimation.

Investigating the Wound-Healing Potential of a Nanoemulsion-Gel Formulation of Pituranthos tortuosus Essential Oil

This study explores a nanoemulsion (NE)-based gel incorporating Tunisian Pituranthos tortuosus essential oil, with a focus on its wound-healing potential. The essential oil, extracted via hydrodistillation, underwent GC-MS analysis for compositional verification. The physicochemical characterization included dynamic light scattering (DLS), transmission electron microscopy (TEM), zeta potential measurement, pH, and viscosity. The gelification of the NE facilitated topical application. The results revealed an average extraction yield of 0.45% and identified 38 compounds in the essential oil. The NE exhibited a particle size of 27 ± 0.4 nm, a polydispersity index (PDI) of 0.3, and a zeta potential of -22.8 ± 1.4 mV. The stability of the gelified preparation was confirmed through thermodynamic stability studies, TEM observations, and zeta and size results. In vivo experiments confirmed significant wound-healing effects, highlighting the promising role of the NE-based gel in healthcare advancements. This research underscores the potential of novel phyto-based delivery systems in wound care.

Long-term exposure to several constituents and sources of PM2.5 is associated with incidence of upper aerodigestive tract cancers but not gastric cancer: Results from the large pooled European cohort of the ELAPSE project

It is unclear whether cancers of the upper aerodigestive tract (UADT) and gastric cancer are related to air pollution, due to few studies with inconsistent results. The effects of particulate matter (PM) may vary across locations due to different source contributions and related PM compositions, and it is not clear which PM constituents/sources are most relevant from a consideration of overall mass concentration alone. We therefore investigated the association of UADT and gastric cancers with PM2.5 elemental constituents and sources components indicative of different sources within a large multicentre population based epidemiological study. Cohorts with at least 10 cases per cohort led to ten and eight cohorts from five countries contributing to UADT- and gastric cancer analysis, respectively. Outcome ascertainment was based on cancer registry data or data of comparable quality. We assigned home address exposure to eight elemental constituents (Cu, Fe, K, Ni, S, Si, V and Zn) estimated from Europe-wide exposure models, and five source components identified by absolute principal component analysis (APCA). Cox regression models were run with age as time scale, stratified for sex and cohort and adjusted for relevant individual and neighbourhood level confounders. We observed 1139 UADT and 872 gastric cancer cases during a mean follow-up of 18.3 and 18.5 years, respectively. UADT cancer incidence was associated with all constituents except K in single element analyses. After adjustment for NO2, only Ni and V remained associated with UADT. Residual oil combustion and traffic source components were associated with UADT cancer persisting in the multiple source model. No associations were found for any of the elements or source components and gastric cancer incidence. Our results indicate an association of several PM constituents indicative of different sources with UADT but not gastric cancer incidence with the most robust evidence for traffic and residual oil combustion.

Effective density of inhaled environmental and engineered nanoparticles and its impact on the lung deposition and dosimetry

BACKGROUND

Airborne environmental and engineered nanoparticles (NPs) are inhaled and deposited in the respiratory system. The inhaled dose of such NPs and their deposition location in the lung determines their impact on health. When calculating NP deposition using particle inhalation models, a common approach is to use the bulk material density, ρb, rather than the effective density, ρeff. This neglects though the porous agglomerate structure of NPs and may result in a significant error of their lung-deposited dose and location.

RESULTS

Here, the deposition of various environmental NPs (aircraft and diesel black carbon, wood smoke) and engineered NPs (silica, zirconia) in the respiratory system of humans and mice is calculated using the Multiple-Path Particle Dosimetry model accounting for their realistic structure and effective density. This is done by measuring the NP ρeff which was found to be up to one order of magnitude smaller than ρb. Accounting for the realistic ρeff of NPs reduces their deposited mass in the pulmonary region of the respiratory system up to a factor of two in both human and mouse models. Neglecting the ρeff of NPs does not alter significantly the distribution of the deposited mass fractions in the human or mouse respiratory tract that are obtained by normalizing the mass deposited at the head, tracheobronchial and pulmonary regions by the total deposited mass. Finally, the total deposited mass fraction derived this way is in excellent agreement with those measured in human studies for diesel black carbon.

CONCLUSIONS

The doses of inhaled NPs are overestimated by inhalation particle deposition models when the ρb is used instead of the real-world effective density which can vary significantly due to the porous agglomerate structure of NPs. So the use of realistic ρeff, which can be measured as described here, is essential to determine the lung deposition and dosimetry of inhaled NPs and their impact on public health.