Average Concentration Research Articles

Therapeutic Doses of Efzofitimod Demonstrate Efficacy in Pulmonary Sarcoidosis

BackgroundIn a phase 1b/2a clinical trial of efzofitimod in patients with corticosteroid-requiring pulmonary sarcoidosis, treatment resulted in dose-dependent improvement in key endpoints. We undertook a post hoc analysis pooling dose arms that achieved therapeutic concentrations of efzofitimod (Therapeutic group)versusthose that did not (Subtherapeutic group).MethodsPeripheral blood mononuclear cells incubated with tuberculin-coated beads were exposed to varying concentrations of efzofitimod in anin vitroassay to determine concentrations that inhibited granuloma formation. In the post hoc analysis, we compared time-to-first-relapse and changes in pulmonary function after a protocolised corticosteroid taper in the Therapeutic and Subtherapeutic groups.ResultsEfzofitimod at ≥300 nM (19 µg·mL−1) inhibited granuloma formationin vitro. Based on average efzofitimod serum concentrations achieved in the phase 1b/2a study, the 3 and 5 mg·kg−1dose arms were pooled as the Therapeutic group, while the 1 mg·kg−1arm was pooled with the placebo arm as the Subtherapeutic group. Relapse rates were 54.4% and 7.7% in the Subtherapeutic group and Therapeutic group, respectively. Median time-to-first-relapse in the Subtherapeutic group was 126 days, whereas in the Therapeutic group, only one of 17 patients relapsed by the end of the 24-week study (p=0.017). Slopes analysis showed that forced vital capacity increased in the Therapeutic group, but decreased in the Subtherapeutic group, over the course of the trial (p=0.035).ConclusionTreatment with efzofitimod at therapeutic doses, as compared with a subtherapeutic dose or placebo, was associated with a lower rate of relapse as corticosteroids were tapered.

Experimental study on flame behaviors and dynamic parameters induced by hydrogen jet flame in an enclosed compartment

Hydrogen is considered as one of the most superior future energy carriers due to its clean, low-carbon and extensive sources. However, a wide flammable concentration range and low ignition energy of hydrogen can cause potential safety hazards, including hydrogen jet flames. Currently, a series of hydrogen jet flame experiments were performed in an enclosed compartment with internal dimensions of 1.82 m (L) × 1.99 m (W) × 1.85 m (H), using different nozzle diameters and stagnation pressures. The results indicate that the combustion process can be divided into four stages, including growth stage, relatively stable stage, stretching stage, and self-extinguishing stage. The oxygen concentration in an enclosed compartment decreases rapidly with increasing stagnation pressure. The self-extinguishing time is positively correlated with the compartment volume and negatively correlated with the mass flow rate. Based on thermal equilibrium analysis, the correlations for average gas temperature rise and oxygen concentration were proposed

Wintertime Ozone Surges: The Critical Role of Alkene Ozonolysis

Ozone (O₃) pollution is usually linked to warm weather and strong solar radiation, making it uncommon in cold winters. However, an unusual occurrence of four high O₃ episode days (with maximum hourly concentrations exceeding 100 ppbv and peaking at 121 ppbv) was recorded in January 2018 in Lanzhou city, China. During these episodes, the average daytime concentration of total non-methane volatile organic compounds (TVOCs) reached 153.4 ± 19.0 ppbv, with alkenes—largely emitted from the local petrochemical industry—comprising 82.3 ± 13.1 ppbv. Here we show a photochemical box model coupled with a Master Chemical Mechanism to elucidate the mechanisms behind this unusual wintertime O₃ pollution. We find that the typically low temperatures (−1.7 ± 1.3 °C) and weak solar radiation (263.6 ± 60.7 W m2) of those winter episode days had a minimal effect on the reactivity of VOCs with OH radicals. Instead, the ozonolysis of alkenes generated Criegee intermediates, which rapidly decomposed into substantial ROx radicals (OH, HO₂, and RO₂) without sunlight. This radical production led to the oxidation of VOCs, with alkene ozonolysis ultimately contributing to 89.6 ± 8.7% of the O₃ formation during these episodes. This mechanism did not activate at night due to the depletion of O₃ by the NO titration effect. Furthermore, the findings indicate that a reduction of alkenes by 28.6% or NOx by 27.7% in the early afternoon could significantly mitigate wintertime O₃ pollution. Overall, this study unravels the unique mechanism of alkene-induced winter O₃ pollution and offers a reference for winter O₃ reduction strategies in the petrochemical industrial regions.

Quantitative analysis of soil quality around brick kilns using pollution indices and ANOVA in Jammu district of Jammu and Kashmir, India

The study investigated soil quality around brick kilns in the Jammu district of Jammu and Kashmir, analyzing 200 samples from 50 sites for selected parameters such as pH, electrical conductiv1ity, soil temperature, organic carbon content, organic matter, macronutrients, and heavy metals. The findings revealed that soil electrical conductivity ranged from 0.33 to 0.63 dS/m, with significant differences observed at varying distances from the kilns. Copper concentrations were highest at 5.32 mg/kg near the kilns, while iron and lead levels also varied significantly, indicating potential contamination. The mean soil temperature was recorded to be 27.69°C.The pH values ranged from 6.5 to 7.8, and the average pH of 8.22 indicated the slightly alkaline nature of the soil around the brick kilns. The organic carbon ranged from 0.34% to 1.02%.Soil temperature and electrical conductivity decreased with increasing distance from the kilns, with temperature showing positive correlations with organic carbon, organic matter, nitrogen, potassium, manganese, and iron and negative correlations with pH, phosphorus, zinc, copper, lead, and cadmium. A perfect positive correlation was noted among nitrogen, organic carbon, and organic matter. Heavy metals, except for zinc and manganese, showed positive correlations with each other. The average Zn, Cu, Mn, Fe, Pb and Cd concentration was recorded as 1.07, 1.03, 6.71, 10.30, 37.04 and 1.91 ppm, respectively. The contamination factor indicated moderate contamination with lead and cadmium, while the geo-accumulation index also suggested moderate contamination. The pollution load index reflected unpolluted soil and enrichment factor values for heavy metals ranked as Cd > Pb > Cu > Zn > Mn > Fe.ANOVA results revealed significant variations in electrical conductivity, copper, iron, and lead, underscoring the potential environmental impacts at different distances from the kilns. However, no significant differences were found between agricultural and non-agricultural sites in other physicochemical parameters. These variations highlight the considerable impact of brick kilns on soil health, emphasizing the need for enhanced environmental management and further research to mitigate these effects.

Origins of atmospheric nitrous acid and their contributions to OH radical from ship plumes, marine atmosphere, and continental air masses over South China Sea

Nitrous acid (HONO) is an important source of atmospheric hydroxyl radical (OH). However, HONO abundance in the marine boundary layer remain largely unknown. Here, ship-based measurements were performed to characterize the origins of HONO from ship plumes, marine atmosphere, and continental emissions over South China Sea (SCS) during September 2021. The results showed that the HONO concentrations were measured at substantial levels (1.0 ± 0.8 ppbv) in polluted plumes due to generally high NOx concentrations (52.3 ± 52.5 ppbv). Comparably, much lower HONO concentrations (0.086 ± 0.102 ppbv) were observed for marine atmosphere. During nighttime, the heterogeneous conversion of NO2 was the predominant source of HONO and occurred mainly on the sea surfaces through NO2 deposition. The HONO yield from this deposition (the proportion of NO2 that was converted to HONO) was 0.08 and 0.06 for the marine atmosphere and continental emissions, respectively. In contrast, daytime known HONO formation of marine atmospheric origins was mainly attributed to homogeneous OH + NO reaction, although the contribution of heterogeneous NO2 conversion might not be negligible. Approximately half of HONO sources during daytime are unknown, which were likely from photo-enhanced NO2 conversation on the sea surfaces. Our results showed that for marine atmosphere and ship plumes, the daily contributions of HONO photolysis to OH radical formation were about 20.8 % and 72.2 %, respectively, while the contributions from ozone photolysis were 79.2 % and 27.8 %. An average HONO concentration of 0.17 ppbv was measured in close shore regions when air masses originated from mainland China, with the contributions from HONO and ozone to OH radical of 21.4 % and 78.6 % respectively, similar to those for the marine atmosphere. This study suggests that HONO in the SCS has various sources (e.g., marine atmosphere, ship plumes, and continental emissions) and makes significant contributions to the OH abundance which affects the oxidation capacity in this area.

Alcohol-induced fibroblast growth factor 21 secretion is increased in individuals with alcohol use disorder

BackgroundAlcohol use disorder (AUD) affects 5% of the global population. Despite its high prevalence, the pathophysiology of AUD remains enigmatic, hindering the development of novel therapeutics. Interestingly, the liver hormone fibroblast growth factor 21 (FGF21), which is currently in late-stage clinical trials for the treatment of non-alcoholic steatohepatitis, has been implicated by recent genome-wide association studies as a regulator of alcohol consumption. MethodsThis study aimed to evaluate plasma responses of FGF21 to an alcohol challenge in three groups: 15 males with AUD, 15 healthy males with a father with AUD (Predisposed) and 15 healthy males without any predisposition to AUD (Controls). All participants were investigated after an overnight fast. Assessments, including blood sampling and visual analog scale-assessed desire for alcohol intake, were performed before and for 10 hours after ingesting 0.5 g alcohol per kg body weight over 10 minutes. ResultsThe three groups were age and body-mass index-matched and had normal plasma concentrations of transaminases and FibroScan®-assessed elastography. Baseline FGF21 concentrations did not differ between groups, but individuals with AUD exhibited greater FGF21 responses to alcohol (area under the curve (AUC0-600 min): 954 ± 665 ng/ml × min (mean (standard deviation)) compared to Controls (AUC0-600 min: 453 ± 333 ng/ml × min, P = 0.03) but not Predisposed (AUC0-600 min: 556 ± 429 ng/ml × min, P = 0.11). ConclusionIn conclusion, we demonstrate greater alcohol-induced FGF21 responses in individuals with AUD compared to healthy individuals without paternal predisposition to AUD, suggesting a role for FGF21 in AUD pathophysiology.

Homocysteine, blood pressure and gene–diet interactions in relation to vascular function measures of black South Africans

Background and AimsWe investigated circulating homocysteine (Hcy), a cardiovascular disease (CVD) risk factor, examining its dietary associations to provide personalized nutrition advice. This study addressed the inadequacy of current dietary interventions to ultimately address the disproportionately high incidence of CVD in Black populations. Methods and Results: Cross-sectional analyses of 1,867 Black individuals of the PURE-SA study allowed the identification of dietary intake and cardiovascular measure interactions on three sub-categories: (1) normal blood pressure (BP), hypertension or Hcy-related hypertension (H-type), (2) low, normal or high Hcy concentrations, and (3) Hcy-related genetic combinations. Favorable body composition, but adverse dietary intake and cardiovascular determinants, were observed in higher Hcy categories. H-types, compared to regular hypertensives, had higher alcohol and lower macronutrient and micronutrient consumption. Inverse associations with carotid-radial pulse wave velocity were evident between monounsaturated fatty acid (FA) consumption and H-type hypertension as well as polyunsaturated FA and CBS883/ins68 TT carriers. Energy intake was positively associated with vascular cell adhesion molecule-1 (VCAM-1) in variant CBST883C/ins68 and CBS9276 GG carriers. VCAM-1 was also positively associated with plant protein intake in CBS9276 GG and MTR2756 AA carriers and negatively with total protein intake and CBS9276 GG carriers. Alcohol intake was positively associated with intercellular adhesion molecule-1 in MTR2756 minor allele carriers. Conclusion: Because Hcy gene-diet interactions are evident, personalized nutrition, by adjusting diets based on genetic profiles (e.g., CBS and MTR variations) and dietary interactions (e.g., FAs and proteins), can enhance cardiovascular outcomes by managing Hcy and related hypertension in genetically susceptible individuals.

Dysregulated serum concentrations of fat-soluble vitamins in dogs with chronic enteropathy.

In inflammatory bowel disease (IBD) of humans, nutrient malabsorption can result in fat-soluble vitamin deficiency, especially of vitamin D. In veterinary species, decreased concentrations of vitamin D are relatively common in dogs with chronic enteropathy (CE), but data on the status of other fat-soluble vitamins (FSVs) is lacking. Determine the serum concentrations of retinol, vitamin D, and α-tocopherol in dogs with CE compared with healthy dogs and compare clinical, clinicopathologic variables between CE and healthy dogs to detect associations with decreased FSVs concentrations. Eighteen client-owned dogs with CE and 33 healthy dogs. Serum 25-hydroxyvitamin D (25[OH]D), serum retinol and α-tocopherol concentrations were compared between groups. Correlations and multiple regression modeling were used to examine the relationship between serum 25(OH)D, retinol, and α-tocopherol concentrations and clinical and clinicopathological variables. Dogs with low serum albumin concentrations were more likely to have lower 25(OH)D concentrations than dogs with normal serum albumin concentration. Dogs with CE had higher serum concentrations of retinol, and variable α-tocopherol concentrations. The cause of these dysregulated vitamin concentrations is unclear and requires further study. Dogs with severe forms of CE should be monitored for decreased concentrations of 25(OH)D. Additional studies are needed to evaluate the clinical relevance and the possible benefit of vitamin D supplementation in these patients.

Spatial and Temporal Distribution Characteristics and Cytotoxicity of Atmospheric PM2.5 in the Main Urban Area of Lanzhou City.

PM2.5, as one of the most harmful pollutant in the atmospheric environment and population health, has received much attention. We monitored PM2.5 levels at five sampling sites in the Lanzhou City and collected PM2.5 particles from two representative sites for cytotoxicity experiment. The cytotoxicity of PM2.5 samples on A549 cells and migration ability of the cells were respectively detected by Cell Counting kit-8 (CCK-8) assay and scratch assay. We detected the levels of cellular inflammatory factors and oxidative damage-related biochemical indexes. RT-qPCR was used to detect the mRNA levels of NF-κB and epithelial-mesenchymal transition (EMT)-related genes. We found that the Lanlian Hotel station had the highest PM2.5 annual average concentration. The annual average concentration change curve of PM2.5 showed a roughly "U"-shaped distribution during the whole sampling period. The cytotoxicity experiment showed the viability of A549 cells decreased and the scratch healing rate increased in the 200 and 400μg/mL PM2.5-treated groups. We also found 400μg/mL PM2.5 induced changes in the mRNA levels of NF-κB and EMT-related genes, the mRNA levels of IKK-α, NIK, and NF-κB in the 400μg/mL PM2.5 group were higher than those in the control group. The mRNA levels of E-cadherin decreased and α-SMA increased in the 400μg/mL PM2.5 groups, and the mRNA levels of Fibronectin increased in the 400μg/mL PM2.5 groups. Moreover, we found hydroxyl radical scavenging ability and T-AOC levels were lower, and LPO levels were higher in the 200 and 400μg/mL PM2.5 groups, and the SOD activity of cells in the 400µg/mL PM2.5 group decreased. And compared with the control group, the levels of TNF-α were higher in the 200 and 400μg/mL PM2.5 groups and the levels of IL-1 were higher in the 400μg/mL PM2.5 group. The results indicated that the cytotoxicity of atmospheric PM2.5 was related to oxidative damage, inflammatory response, NF-κB activity and EMT.

Phase distribution and probabilistic risk assessment of polycyclic aromatic hydrocarbons in indoor air of coffee shops at Zahedan, Iran

Polycyclic aromatic hydrocarbons (PAHs) are a class of hydrocarbons, some of which are established human carcinogens. Human exposure to these chemicals is complex and originates from both indoor and outdoor sources. This study measured the concentration of PAHs in the gaseous and particulate phases during the cold months of 2022 using XAD-2 sorbent tubes and Polytetrafluoroethylene (PTFE) filters in the indoor air of coffee shops in Zahedan, Iran (n=23). The average concentrations of particulate-bound PAHs and gaseous PAHs were 13,411.86 ± 6,517.24 ng/m³ and 6,432.76 ± 4,311.72 ng/m³, respectively. Source apportionment analyses indicated that the primary sources of PAHs in coffee shops were fossil fuel combustion and environmental tobacco smoke (ETS), commonly referred to as second and third-hand smoke. The lifetime cancer risk (LTCR) of inhaled PAHs was calculated using the Monte Carlo simulation method. The mean LTCR for adults and children from inhaling these substances were 9.43×10 - 6 ± 5.06 ×10 - 6 and 5.34×10 - 6 ± 2.87 ×10 - 6, respectively. The hazard quotient (HQ) of PAHs exceeded 1. These findings highlight the need to reduce PAHs exposure in public spaces through proper health warning labels and regulated indoor smoking policies.

Impact of air pollution on human morality: A multinational perspective

This study aimed to investigate whether global air pollution harms human morals beyond physiological and psychological health. To accomplish this, we conducted an original survey involving over 80,000 individuals across 30 countries, inquiring about their recent perceived unethical behaviors. Through regression analyses, we identified global evidence of a positive correlation between local monthly average concentrations of nitrogen dioxide (NO2) and perceptions of unethical behavior. This finding suggests that air pollution may potentially elicit unethical behavior through a complex response mechanism. It is noteworthy that the impact of air pollution on the inclination to perceive unethical behavior is heterogeneous across categories of unethical behavior and countries. For example, the effects of increasing air pollution concentrations vary even within the same European country: an increase in NO2 concentration in Greece and the Netherlands augments the inclination to perceive fatal unethical behaviors such as murder, terrorism, and suicide, while in Germany, NO2 concentration diminishes the inclination to perceive the same types of unethical behaviors. Overall, the societal costs of air pollution may be even more far-reaching than previously acknowledged, and further research is necessary to unveil the intricate response mechanisms underlying this issue.

Optical characteristics of brown carbon in the atmospheric particulate matter of Dhaka, Bangladesh: Analysis of solvent effects and chromophore identification

The prevalence of brown carbon (BrC) in the atmosphere has experienced a notable upsurge owing to human activities of anthropogenic origin. This study aims to examine the optical characteristics of BrC in both deionized (DI) water and organic solvents (OS), alongside the identification of BrC chromophores within the ambient atmosphere of Dhaka, Bangladesh. Particulate matter (PM) samples were collected on quartz filters using a low-volume sampler from December 2021 to May 2022 at Mukarram Hussain Khundker Bhaban, University of Dhaka. The concentration of BrC was measured using soot analyzer, optical properties of BrC were determined using UV–Vis spectrometer, and BrC chromophores were identified with GC-MS. Average concentration of BrC was 19.13 ± 5.71 μgm−3. The average of absorption coefficient (babs_365), mass absorption efficiency (MAE), absorption angstrom exponent (AAE), and refractive index (kabs_365) of BrC_DI have been observed to be 38.75 ± 21.90 Mm−1, 2.16 ± 1.42 m2 g-1, 1.51 ± 0.08, 0.06 ± 0.04, respectively. The absorption coefficient and MAE of BrC_OS are 1.3 and 1.36 times, respectively higher than that of BrC_DI. Thirty chromophores of BrC have been identified, predominantly consisting of oxygenated compounds. Derivatives of Bisphenol A (C27H44O2Si2) were detected in all samples of oxygenated compounds, primarily originating from the combustion of plastic and the incineration of e-waste. Additionally, compounds containing nitrogen and sulfur, such as C14H26N2O, C31H55N, and C31H49NO3S, were identified, largely attributed to biomass combustion and traffic emissions. These chromophores play a significant role in the absorption of solar radiation, thus influencing atmospheric photochemistry.

Bioaccumulation of Heavy Metals in Water and Mollusks in the Karnafully Estuary: Potential Human Health Risk and Environmental Contamination

This study investigates the bioaccumulation of heavy metals lead (Pb), cadmium (Cd), copper (Cu), and chromium (Cr) in water and mollusks across the Karnafully River estuaryof Bangladesh. Samples were collected from six different sites encompassing diverse ecological conditions over three seasons: monsoon, post-monsoon, and winter. Six mollusk species were analyzed using atomic absorption spectrophotometry to quantify metal concentrations in both tissues and shells. These species are Neritina violocea, Neritina sulculosa, Telescopium telescopium, Cerithidaecingulata, Corbiculatafluminea, and Bellamya bengalesis. The Chaktai canal site had the highest concentration of Cu (13.99±0.92mg/kg) from the mussel species B. Bengalesis during monsoon season, which was higher than the tolerable limit for human. The the lowest concentration of Cu (1.13±0.76mg/kg) from the composite mussel species N. sulculosa were fround from the 15 No. Jetty site in winter.. The highest concentration of Cr was found at the Marine Academy site (0.54±0.24mg/kg) during the post-monsoon period from the mussel species N. violocea, while the lowest concentration was found near the Karnafully Bridge (0.05±0.02mg/kg) during the monsoon from the mussel species Cerithidaecingulata. The highest concentration of Cd was observed in the Chaktai canal site (0.77±0.04mg/kg) during the winter from the B. bengalesis, and the lowest concentration was recorded in the Karnafully Bridge (0.33±0.06mg/kg) site during the winter season from the Cerithidae cingulata species. The highest amount of Pb was found in Chaktai canal site (0.32±0.06mg/kg) during the monsoon season in B. bengalesis fuana. The lowest amount was found in Karnafully Bridge (0.09±0.02mg/kg) in the Cerithidae cingulate species at the same time. The results suggested that the possibility of the occurrence of acute toxicities of CU, Cr, Cd and Pb was unlikely except for the mussel of T. telescopium in the Marine Academy that indicates heavy metals presence at the Marine Academy site. The study revealed that the average concentrations of the heavy metals were in the order of Cu>Cd>Cr>Pb in the monsoon, postmonsoon, and winter seasons. The principal Component Analysis (PCA) highlighted distinct seasonal patterns in metal accumulation, underscoring the need for seasonal-specific monitoring and management strategies in estuarine ecosystems.

The Association between Exposure to Fine Particulate Air Pollution and the Trajectory of Internalizing and Externalizing Behaviors during Late Childhood and Early Adolescence: Evidence from the Adolescent Brain Cognitive Development (ABCD) Study.

Exposure to high levels of fine particulate matter (PM) with aerodynamic diameter () via air pollution may be a risk factor for psychiatric disorders during adulthood. Yet few studies have examined associations between exposure and the trajectory of symptoms across late childhood and early adolescence. The current study evaluated whether exposure at 9-11 y of age affects both concurrent symptoms as well as the longitudinal trajectory of internalizing and externalizing behaviors across the following 3 y. This issue was examined using multiple measures of exposure and separate measures of symptoms of internalizing disorders (e.g., depression, anxiety) and externalizing disorders (e.g., conduct disorder), respectively. In a sample of more than 10,000 youth from the Adolescent Brain Cognitive Development (ABCD) Study, we used a dataset of historical levels and growth curve modeling to evaluate associations of exposure with internalizing and externalizing symptom trajectories, as assessed by the Child Behavioral Check List. Three distinct measures of exposure were investigated: annual average concentration during 2016, number of days in 2016 above the US Environmental Protection Agency (US EPA) 24-h standards, and maximum 24-h concentration during 2016. At baseline, higher number of days with levels above US EPA standards was associated with higher parent-reported internalizing symptoms in the same year. This association remained significant up to a year following exposure and after controlling for annual average, maximum 24-h level, and informant psychopathology. There was also evidence of an association between annual average and externalizing symptom levels at baseline in females only. Results suggested exposure during childhood is associated with higher symptoms of internalizing and externalizing disorders at the time of exposure and 1 y later. In addition, effects of exposure on youth internalizing symptoms may be most impacted by the number of days of exposure above US EPA standards in comparison with annual average and maximum daily exposure. https://doi.org/10.1289/EHP13427.

Long-term impact of Hurricane Maria on point-of-use drinking water quality in Puerto Rico and associated potential adverse health effects

Drinking water security in Puerto Rico (PR) is increasingly challenged by both regulated and emerging anthropogenic contaminants, which was exacerbated by the Hurricane Maria (HM) due to impaired regional water cycle and damaged water infrastructure. Leveraging the NIEHS PROTECT (Puerto Rico Testsite for Exploring Contamination Threats) cohort, this study assessed the long-term tap water (TW) quality changes from March 2018 to November 2018 after HM in PR, by innovatively integrating two different effect-based quantitative toxicity assays with a targeted analysis of 200 organic and 22 inorganic pollutants. Post-hurricane PR TW quality showed recovery after >6-month period as indicated by the decreased number of contaminants showing elevated average concentrations relative to pre-hurricane samples, with significant difference of both chemical and toxicity levels between northern and southern PR. Molecular toxicity profiling and correlation revealed that the HM-accelerated releases of certain pesticides and PPCPs could exert increased cellular oxidative and/or AhR (aryl hydrocarbon receptor)-mediated activities that may persist for more than six months after HM. Maximum cumulative ratio and adverse outcome pathway (AOP) assessment identified the top ranked detected TW contaminants (Cu, Sr, V, perfluorooctanoic acid) that potentially associated with different adverse health effects such as inflammation, impaired reproductive systems, cancers/tumors, and/or organ toxicity. These insights can be incorporated into the regulatory framework for post-disaster risk assessment, guiding water quality control and management for public health protection.

Evaluation of ground water quality using heavy metal pollution indices and estimation of health risk

ABSTRACT This paper presents the monitoring of heavy metals, including cadmium (Cd), chromium (Cr), lead (Pb), copper (Cu), and zinc (Zn), in the groundwater of the Byrnihat Industrial Area and Guwahati City, which is located in close proximity to the Byrnihat Industrial Area. A total of 20 water samples were collected at distances approximately 1–2 km apart from each other. The pH and the TDS of the collected samples were analysed immediately after collecting samples using a digital pH and TDS meters. The collected samples were analysed using a Flame type Atomic Absorption Spectrophotometer. The highest observed values of Cd, Cr, Pb, Cu and Zn in mg/L were recorded to be 0.0526, 0.1438, 0.5175, 0.1060 and 0.0925, respectively. The average values of Cd, Cr, Pb, Cu and Zn were 0.0246 ± 0.0168 mg/L, 0.0282 ± 0.0421 mg/L, 0.4805 ± 0.0206 mg/L, 0.0653 ± 0.0276 mg/L, and 0.0642 ± 0.0098 mg/L, respectively. Cd and Pb concentrations were above the guideline values set by Bureau of Indian Standards (BIS) and the World Health Organisation (WHO) [WHO recommended values, Cd: 0.003 mg/L, Pb: 0.01 mg/L]. Though the average concentration of Cr was below the allowable limit, five samples within the Byrnihat industrial area were found to be above the limit. High values of pollution indices was observed for all the samples. The cumulative hazard index (HI) values for adults and children were found to be 8.56 and 9.37, respectively. The total cancer risk (TCR) was observed to be 7.87E-03 for adults and 8.54E-03 for children. The result obtained from the present investigation show significant contamination of ground water by heavy metals, particularly Pb, Cd, and Cr concentrations. The observed high values of hazard index and cancer risks indicate significant health risks, necessitating the need for immediate regulatory action.

Exploration of trace elements in groundwater and associated human health risk in Chattogram City of Bangladesh

The study aimed to evaluate trace metals in the groundwater of Chattogram City located on the southeastern coast of Bangladesh and assess their potential health risks. Given the city's unique characteristics as both a coastal and industrial hub in Bangladesh, a knowledge gap persists particularly in the assessment of trace metals. A random sampling technique was applied to collect one hundred and seventeen groundwater samples from different wards of the city to analyze some trace metals (Cr, Cd, Fe, Cu, Mn, Pb, and Zn) and the quality of the collected water samples was evaluated using different indices, such as Heavy Metal Evaluation Index (HEI), Groundwater Quality Index (GWQI), Heavy Metal Pollution Index (HPI), and Degree of Contamination (Cd). The average concentration of all the studied metals except Fe, Mn, and Cd satisfied the Bangladesh drinking water standards. The Fe, Mn, and Cd content were observed higher in shallow wells (depth 10–150 ft) followed by intermediate (151–300 ft) and deep wells (>300 ft). However, the Cr, Cu, and Zn content did not significantly change with aquifer depth. The spatial distribution map showed that the highest values of Mn and Cu were observed in the west-northern region of the city. Metal As was only found in shallow and intermediate aquifers. The HEI suggested that about 9 % of samples fall into the higher degree of pollution category similar to the GWQI, while 37 % and 42 % of samples exhibited a higher degree of pollution in the case of HPI and Cd, respectively. The positive correlations and loadings found in the statistical analysis indicated that Fe, Mn, and Cu originated from the same sources. A variety of industrial activities might be ascribed to this type of pollution. However, an average Hazard Quotient (HQ) through ingestion was found to be greater than 1 for Cd, and the Carcinogenic Risk (CR) values for children were identified as two-fold higher than that of adults. Raising social awareness, avoiding the usage of groundwater without proper treatment, and strict regulations and monitoring by the concerned authority are recommended in the study.

Pollution level and distribution characteristics of heavy metals and microplastics in the soils from the Qionghai Lake Wetland, Southwest China

Urban wetlands are reported to be ideal habitats for accumulation of HMs and MPs. However, study on combined pollution of HMs and MPs in soil is rare in urban wetland environment. In this study, the characteristics of HMs and MPs in the soils of the Qionghai Lake wetland in southwest China were studied by using ICP–MS, and FTIR. The results showed that the average concentration of HMs in soil ranges from 0.84 to 552.75 (mg/kg). According to the EF and Igeo analysis results, Cd and Cr in the soil were significant enriched (EF=12.64) and moderately enriched (EF=2.09), and were at the moderate to heavy pollution level (Igeo = 2.83) and the unpolluted to moderate pollution level (Igeo = 0.23), and the other elements were at a low level. MPs are emerging micropollutants in the soil environment, and the abundance (pieces/g) of MPs in the soil was 3.90, 7.00, 3.10, 3.40, 14.80, and 1.10 at Stations M1, M2, M3, M4, M8, and M9, respectively, with an average of 5.55 ± 4.92. Films represented the main microplastic shape, accounting for 81.55 %, followed by fibers, accounting for 11.33 %. The proportion of MPs with a particle size of 0.1–0.5 mm is the highest. Black, blue, and green are the predominant colors found in MPs. Polyethylene (PE) and polypropylene (PP) were the main MP materials based on FTIR identification, accounting for 52.16 % and 42.31 % of the total MPs, respectively. The pollution load index (PLI) of MPs was 2.2, which is a level Ⅰ pollution. The research on HMs and MPs in urban wetland soil is still in its preliminary stage. Our aim is to offer a fresh perspective for evaluating the pollution status and risk associated with these two pollutants in urban wetland soil, while also providing a valuable reference for subsequent studies on wetland soil pollutants.

Meibomian Gland Shortening Is Associated With Altered Meibum Composition.

The purpose of this study was to investigate differences in the composition of meibum extracted from human meibomian glands displaying different morphological characteristics. Adult participants with evidence of meibomian gland shortening were enrolled. Glands were observed using infrared meibography, and meibum was collected from one short and one long gland from the lower eyelid of the same eye. Total protein concentration was evaluated using the detergent compatible (DC) protein assay and lipid analysis was performed using liquid chromatography mass spectrometry. Fifteen participants (8 women and 7 men) completed the study (mean age = 34.7 ± 7.7 years). The average volume of meibum collected from the short and long glands was 0.02 ± 0.01 and 0.05 ± 0.03µL, respectively (P=0.01). Average protein concentration in the short glands was significantly higher compared to the long glands (0.10 ± 0.03 vs. 0.08 ± 0.02 mg/mL, P=0.01). Among the non-polar lipids, the mole percent of cholesterol esters (CEs; P=0.02), triacylglycerols (TAGs; P=0.04), and ceramide (Cer; P=0.03) was significantly lower in short glands compared with long glands. Among the polar lipids, the mole percent of (O-acyl)-ω-hydroxy fatty acid (OAHFA; P=0.01) was significantly lower in short glands, whereas phosphatidylcholine (PC; P=0.02) and sphingomyelin (SM; P=0.01) were significantly higher in short glands than long glands. Meibum composition differed between short and long glands. The lower mole percent of CE, TAG, OAHFA, and Cer and a higher mole percent of PC and SM among short glands may indicate disease activity. This information may clarify the natural history of meibomian gland dysfunction and future targets for therapy.

Predicting clearance with simple and permeability-limited PBPK frameworks: comparison of well-stirred, dispersion and parallel tube liver models.

One-compartment (1C) and permeability-limited models were used to evaluate the ability of microsomal and hepatocyte intrinsic clearances to predict hepatic clearance. Well-stirred (WSM), parallel tube (PTM), and dispersion (DM) models were evaluated within the liver as well as within whole-body physiologically based pharmacokinetic frameworks. It was shown that a linear combination of well-stirred and parallel-tube average liver blood concentrations accurately approximates dispersion model blood concentrations. Using a flow/permeability-limited model, a large systematic error was observed for acids and no systematic error for bases. A scaling factor that reduced interstitial fluid (ISF) plasma protein binding could greatly decrease the absolute average-fold error (AAFE) for acids. Using a 1C model, a scalar to reduce plasma protein binding decreased the microsomal clearance AAFE for both acids and bases. With a permeability-limited model, only acids required this scalar. The mechanism of the apparent increased cytosolic concentrations for acids remains unknown. We also show that for hepatocyte intrinsic clearance in vitro-in vivo correlations (IVIVCs), a 1C model is mechanistically appropriate since hepatocyte clearance should represent the net clearance from ISF to elimination. A relationship was derived that uses microsomal and hepatocyte intrinsic clearance to solve for an active hepatic uptake clearance, but the results were inconclusive. Finally, the PTM model generally performed better than the WSM or DM models, with no clear advantage between microsomes and hepatocytes. Significance Statement Prediction of drug clearance from microsomes or hepatocytes remains challenging. Various liver models (e.g. WSM, PTM, and DM) have been mathematically incorporated into liver as well as whole-body PBPK frameworks. Although the resulting models allow incorporation of pH partitioning, permeability, and active uptake for prediction of drug clearance, including these processes did not improve clearance predictions for both microsomes and hepatocytes.