Highly fluorescent CdTe/ZnSe quantum dot-based "turn-off" sensor for the on-site rapid detection of Lead ions in aqueous medium.

Lead (Pb) is a heavy metal known for its adverse effects on both human health and the environment. In recent years, the industrial utilization of Pb2+ has surged, underscoring the imperative need for efficient measurement methods. In this study, a rapid and simple photochemical method was used to synthesize thioglycolic acid (TGA)-stabilized CdTe/ZnSe core-shell quantum dots (QDs). These CdTe/ZnSe QDs emit vibrant green fluorescence and exhibit remarkable quenching in the presence of Pb2+ ions. This property enables the development of an on-site on/off sensor without the necessity of additional modifications. The proposed sensor possesses an outstanding sensitivity to Pb2+, with a detection limit and linear range of 31.8 nM and 50 nM-10 µM, respectively. Importantly, the selectivity of this fluorescence-based sensor was validated by analyzing various positively and negatively charged ions. Furthermore, the developed sensor showed reliable performance against real river, agricultural, and tap water, as confirmed by Inductively Coupled Plasma (ICP) analysis. Additionally, CdTe/ZnSe QDs immobilized on glass slides were successfully employed for on-site water sample analysis, providing a versatile solution for environmental monitoring.

Unraveling the Fluoride-Induced Interface Reconstruction Across Lead-Based Hierarchical MnO2 Anode in Zinc Electrowinning.

Although the hierarchical manganese dioxide film electrode shows promise as a durable and catalytically active anode for zinc electrowinning, it often fails and deactivates when it is exposed to fluoride-rich environments. The lack of understanding regarding the mechanism behind fluoride-induced irreversible interface reconstruction hinders their practical application in large-scale energy-saving and pollution-reduction efforts. Here, we conducted multidimensional operando investigations to gain insights into the dynamic evolution across the film electrode interface with temporal and spatial resolution. Our findings reveal that electroosmosis of F- initially triggers structural collapse and subsequent reconstruction of [MnO6] units, followed by interaction with the spontaneous oxide film at the surface of lead substrate. Experimental studies and theoretical calculations indicate that F- facilitates the irreversible transformation of γ-MnO2 into more stable yet protective catalytic dual-defective α-MnO2. Additionally, lower levels of F- at the interface promote a change in microenvironmental pH within porous PbSO4, triggering the development of microporous corrosion-resistant ß-PbO2 as the dominant phase. The combined effects of MnO2 and interphase evolution effectively explain the abnormally elevated oxygen evolution overpotential. Then, the proposed appropriate application scenarios based on the corrosion behavior will serve as a practical guide for the implementation of the hierarchical manganese dioxide film electrode.

Plasma-Based Modification of Tin Halide Perovskite Interfaces for Photovoltaic Applications.

Tin halide perovskites represent the most suitable alternative to their lead-based counterparts for sustainable photovoltaics. One of the most important drawbacks of this class of materials is the intrinsic tendency of tin (II) to oxidize under certain conditions and as a consequence of aging. Here, we explore plasma processing to gently treat the surface of the tin perovskite films. As shown by chemical, optical, and morphological analyses, this treatment by generating transient active species on the surface of the material impacts its aging, inhibiting the tendency of tin (II) to oxidize. Plasma-treated stored devices show a power conversion efficiency slightly higher and narrower in the distribution than that of the reference devices. The positive impact of this noninvasive technique, which can be easily implemented in large-area manufacturing facilities, increases the potential of lead-free alternative perovskite photovoltaics.

The Loop Technique in Cardiac Resynchronization Therapy: A Prospective Cohort Study.

Objective: A new approach called the loop technique has been proven safe and effective for repeated intraoperative transvenous left ventricular (LV) lead dislocations during cardiac resynchronization therapy (CRT) in a 3-year follow-up. This study aimed to report on the 5-year safety and effectiveness of the loop technique. Methods: This study was a prospective cohort study. Forty-four patients who underwent CRT device implantation at the Cardiology Department of Shaanxi Provincial People's Hospital between January 2013 and June 2019 were included. Data on patient demographics, medical history, laboratory test results, and echocardiography images at admission were collected. The loop technique was performed with repeated intraoperative dislocations of the LV lead. The intraoperative CRT parameters were also recorded. All patients were followed for 5 years. Several auxiliary examinations were performed during follow-up. Results: The 44 patients were divided into the traditional operation group (n=36, 81.8%) and loop technique group (n=8, 18.2%). The baseline patient characteristics were almost balanced. During the 5-year follow-up, 8 (22.2%) patients in the traditional operation group and 2 (25.0%) patients in the loop technique group died. No lead dislocation or other complications related to CRT were observed. There were no significant differences in mortality rate (P=0.87), cardiac function (P=0.56), echocardiographic indices, threshold (P=0.58), or impedance (P=0.22) of the LV lead. There were no significant differences in the threshold and impedance between postoperative, 3-year, and 5-year follow-ups in the loop technique group (P=0.53). Conclusion: The loop technique is an ideal solution for repeated intraoperative LV lead dislocation during CRT implantation.

Rational Design of A-Site Cation for High Performance Lead-Free Perovskite X-Ray Detectors.

Design of hypotoxic lead-free perovskites, e.g. Bismuth(Bi)-based perovskites, is much beneficial for commercialization of perovskite X-ray detectors due to their strong radiation absorption. Nevertheless, the design principles governing the selection of A-site cations for achieving high-performance X-ray detectors remain elusive. Here, seven molecules (methylamine MA, amine NH3, dimethylbiguanide DGA, phenylethylamine PEA, 4-fluorophenethylamine p-FPEA, 1,3-propanediamine PDA, and 1,4-butanediamine BDA) and calculated their dipole moments and interaction strength with metal halide (BiI3) are selected. The first-principles calculations and related spectroscopy measurements confirm that organic molecules (DGA) with large dipole moments can have strong interactions with perovskite octahedron and improve the carrier transport between the organic and inorganic clusters. Consequently, zero-dimensional single crystal (SC) (DGA)BiI5∙H2O is synthesized. The (DGA)BiI5∙H2O SCs demonstrate an exceptional carrier mobility-lifetime product of 6.55 × 10-3 cm2 V-1, resulting in the high sensitivity of 5879.4 µCGyair -1cm-2, featuring a low detection limit (4.7 nGyair s-1) and remarkable X-ray irradiation stability even after 100 days of aging at a high electric field (100 V mm-1). Furthermore, the (DGA)BiI5∙H2O SCs for imaging, achieving a notable spatial resolution of 5.5 lp mm-1 are applied. This investigation establishes a pathway for systematically screening A-site cations to design low-dimensional SCs for high-performance X-ray detection.

Photoaged tire wear particles hinder the transport of Pb(II) in urban soils under acid rain: Experimental and numerical investigations.

Rapid urbanization brought lots of serious environmental contamination, including the accumulation of heavy metals, acid rain, and the emission of tire wear particles (TWPs), with detrimental effects for terrestrial ecosystems. Nevertheless, how naturally aged TWPs affect the mobilization of heavy metals in soils under acid rain is still unclear. Here, we investigate the adsorption and transport mechanisms of Pb(II) co-existing with acid rainwater in soil-TWP mixtures via batch experiments, column experiments and modeling. Results showed that photoaged TWP significantly prolonged the Pb(II) adsorption equilibrium time (1 to 16 h) and enhanced the Pb(II) adsorption capacity of soils. Soil column profiles confirmed that TWP effectively boosted the initial accumulation of lead in the topsoil and thus impeded the downward transport of lead. The retardation factor (R) estimated by the linear two-site sorption model (TSM) fitting the Pb(II) breakthrough curves gradually increased from 1.098 to 16.38 in soils with TWP (0-10 %). Comparative results of linear or nonlinear TSM suggested nonlinear sorption replacing linear sorption as the main Pb(II) sorption mechanism under 1 % and 10 % TWP. This research provides significant insights into the implications of TWP on the Pb(II) retention behaviors and highlights the severer potential remobilization risks of Pb(II) in urban soils under different acid rain environments.

Case Report: Extraction of a stylet-driven lead for left bundle branch area pacing >2†years after implantation.

Left bundle branch pacing has recently emerged as a significant alternative to right ventricular pacing. The rate of implanted stylet-driven septal leads is expected to increase substantially in the coming years, along with the need to manage long-term complications. Experience in extracting these leads is currently very limited; however, the number of complex extractions is anticipated to increase in the future. We report a complex case involving the extraction of a long-dwelling Solia lead used for left bundle branch pacing in a 21-year-old man. The lead was extracted through the implant vein 27 months after implantation, using a methodology that involved a locking stylet and compression coil. The new lead insertion was challenging due to venous occlusion but after successful venoplasty, the His lead was successfully implanted. The postoperative course was uneventful, demonstrating the feasibility of extraction without complications.

Bone lead measurements of live condors in field to assess cumulative lead exposure.

Lead poisoning remains the leading cause of diagnosed death for critically endangered California condors, which are annually monitored for lead exposure via blood tests. Blood tests are generally reflective of acute lead exposure. Since condors are victims to both chronic and acute lead exposure, measuring bone, which in humans is reflective of years to decades worth of exposure, is a valuable biomarker. In this study, we measured bone Pb of the tibiotarsus of 64 condors in vivo using a portable x-ray fluorescence device. The average uncertainty for measurements, typically reflective of how effective the device performed, was found to be 3.8 ± 2.2 µg/g bone mineral. The average bone lead level was found to be 26.7 ± 24.5 µg/g bone mineral. Bone lead correlated significantly with a sum of all blood lead measures over the lifetime of each condor. In the future, bone lead can potentially be used to inform treatment planning and address the chronic health implications of lead in the species.

Chronic effects of metal releases from historical mining on threatened crayfish in Madison County Missouri, USA.

The Little St. Francis River and its tributaries drain metals-contaminated areas of the Madison County Mines National Priority List Superfund site (MCM) which was designated in 2003 to facilitate remediation of metals contamination within the MCM. One concern for natural resource trustees in the MCM is the potential effects of elevated metals concentrations on the federally threatened St. Francis River crayfish, Faxonius quadruncus, which has a geographic range that is limited to the St. Francis River watershed. A survey of riffle-dwelling crayfish, in-situ cage study, and laboratory toxicity tests were conducted to assess the effects of mining-derived metals on F. quadruncus and other crayfish species in the MCM. Crayfish densities were significantly greater at sites upstream of metals releases from historical mining (henceforth mining releases) compared to densities at sites downstream of mining releases, and metals concentrations in whole-body crayfish, surface water, sediments, macroinvertebrates, fish, and plant material were greater at sites downstream of mining releases compared to sites upstream of mining releases. Crayfish densities were also negatively correlated with consensus-based adverse effects indices, expressed as surface-water toxic units and sediment probable effects quotients. Decreased growth and increased mortality during cage and laboratory studies were likely due to exposure to, and subsequently uptake of, elevated concentrations of metals. Crayfish in all studies were found to bioaccumulate metals, which supports their utility as bioindicators of metals contamination. Study results show that elevated metals concentrations associated with mining releases in the MCM continue to adversely affect biota, including the federally threatened F. quadruncus.

Determination of dielectric properties of lead-contaminated soils: Potential application to soil remediation.

This research investigated the effectiveness of radio frequency (RF) heating as a treatment for lead-contaminated soil, assessing its impact through dielectric constant measurements. Using water-soluble lead (II) acetate trihydrate, the study analyzed the impact of RF heating on soil dielectric properties under various soil moisture conditions (high, medium, and low) and electric field strengths (112.5, 150, 225, and 450 kV/m). The results indicated that soil temperature increased with lead concentration, highlighting significant changes in soil thermodynamics. Under high-humidity conditions, temperature increases were more pronounced, suggesting that higher lead concentrations elevate soil temperatures. Moreover, RF heating consistently reduced the dielectric constant as lead concentration increased, which was especially evident at higher electric field strengths. The study found that the soil resistivity approached that of uncontaminated soil, particularly at 450 kV/m electric field strength, with the highest removal rate of 46.154%. This investigation provides valuable insights into the application of RF heating for soil quality improvement in lead-contaminated environments, demonstrating how dielectric properties can reflect those of uncontaminated soil.

Cadmium contamination in sediments from a mangrove wetland: Insights from lead isotopes.

Cadmium (Cd) pollution has gained significant attention in mangrove sediments due to its high toxicity and mobility. However, the sources of Cd and the factors influencing its accumulation in these sediments have remained elusive. In this study, we utilized lead (Pb) isotopic signatures for the first time to assess Cd contamination in mangrove sediments from the northern region of the Beibu Gulf. A strong correlation was observed between Cd and Pb concentrations in the mangrove sediments, suggesting a shared source that can be estimated using Pb isotopic signatures. By employing a Bayesian mixing model, we determined that 70.1 ± 8.2 % of Cd originated from natural sources, while 12.9 ± 4.9 %, 9.8 ± 3.7 %, and 7.1 ± 3.4 % were attributed to agricultural activities, non-ferrous metal smelting, and coal combustion, respectively. Our study clearly suggests that natural Cd could also dominate the high Cd content. Agricultural activities were the most important anthropogenic Cd sources, and the increased anthropogenic Cd accumulation in mangrove sediment was related to organic matter. This study introduces a novel approach for assessing Cd contamination in mangrove sediment, providing useful insights into Cd pollution in coastal wetlands.

Ammonia-sensitive halide CsCu2I3 film for gas sensor and stimuli-responsive anti-counterfeiting.

Eco-friendly lead-free halide perovskites have emerged as promising materials for multiple applications due to their unique optoelectronic properties. In this work, we investigate the ammonia (NH3)-sensitive CsCu2I3 film for its potential in NH3 sensor and stimuli-responsive fluorescence anti-counterfeiting. CsCu2I3-based NH3 sensor demonstrates a high response to NH3 (△R/R0 = 1.07, at 100 ppm NH3) with rapid response/recovery time (21/19 s), as well as favorable gas selectivity. We proposed a potential NH3 sensing mechanism with the help of a series of semi-quantitative characterizations and excitation-dependent emission experiments. The electron-donating NH3 molecules can efficiently donate electrons to the p-type CsCu2I3 film, bringing about a decrease in film conductivity. Additionally, the adsorption of NH3 can also disorder the CsCu2I3 crystals with a high density of trap states, facilitating an energy transfer from self-trapped excitons (STEs) emission to defect-related emission, along with bright orange luminescence. Inspired by this phenomenon, we proposed a novel application of NH3-induced stimuli-responsive fluorescence for anti-counterfeiting. The results highlight the potential of CsCu2I3 for effective dual-function applications in gas sensors and gas-triggered anti-counterfeiting.

Pharmacological and biochemical insights into lead-induced hepatotoxicity: Pathway interplay and the protective effects of arbutin via the oral and intraperitoneal routes in silico and in vivo.

INTRODUCTION: Lead acetate (PbAc), a hazardous heavy metal, poses significant threats to human health and the environment because of widespread industrial exposure. PbAc exposure leads to liver injury primarily through oxidative stress and the disruption of key regulatory pathways. Understanding these mechanisms and exploring protective agents are vital for mitigating PbAc-induced hepatotoxicity. Therefore, we aimed to investigate the molecular pathways implicated in PbAc-induced liver damage, focusing on Sirt-1, Nrf2 (HO-1, NQO1, and SOD), Akt-1/GSK3ß, m-TOR, and P53. Additionally, we aimed to assess the hepatoprotective effects of arbutin, which is administered orally and intraperitoneally, to determine the most effective delivery method. METHODOLOGY: In silico analyses were conducted to identify relevant protein networks associated with Sirt-1 and AKT-1/GSK-3B pathways. The pharmacodynamic properties of arbutin were examined, followed by molecular docking studies to elucidate its interactions with the selected protein network. In vivo preclinical studies were carried out on adult male rats randomly assigned to 6 different treatment groups, including PbAc exposure and PbAc exposure treated with arbutin either orally or intraperitoneally. RESULTS: PbAc exposure led to hepatic oxidative stress, as evidenced by elevated MDA levels and SIRT-1 inhibition, disrupting antioxidant pathways and activating antiautophagic and proapoptotic pathways, ultimately resulting in hepatocyte necrosis. Both oral and intraperitoneal arbutin administration effectively modifed these effects, with intraperitoneal delivery showing superior efficacy in mitigating PbAc-induced histological, immunological, and biochemical alterations. CONCLUSION: This study provides insights into the molecular mechanisms underlying PbAc-induced liver injury and highlights the hepatoprotective potential of arbutin. These findings suggest that arbutin, particularly when administered intraperitoneally, holds promise as a therapeutic agent for combating PbAc-induced hepatotoxicity.

Infants' and young children's dietary exposures to lead and cadmium: FDA total diet study 2018-2020.

Food can be a source of lead and cadmium exposure for infants and children. Employing a semi-probabilistic approach, dietary exposures to lead and cadmium were assessed for infants 0-11 months (excluding human milk-fed infants) and children 1-6 years using U.S. total diet study data from 2018 to 2020 and food consumption data from 2015 to 2018. Estimated mean lead and cadmium exposures range from 0.7-3.6 µg/day to 0.18-0.47 µg/kg bw/day, respectively, depending on the age group and method for handling non-detected values. Dietary exposures to lead and cadmium are slightly lower and slightly higher than our estimates published in 2019. In addition to the use of more recent datasets for consumption and contamination, differences may be due to the use of refined exposure assessment methodology, particularly a new system of mapping contamination data to intake data. The processed baby food and infant formula food group is the major contributor to lead and cadmium exposure, driven by intake, among infants who do not consume human milk. The food groups contributing most to children's lead and cadmium exposure are grains/baking, dairy and fruit and grains/baking and vegetables, respectively. This work will inform FDA initiatives such as closer to zero, including research needs and regulatory priorities.

Indications and outcomes of elective open chest lead extractions.

BACKGROUND: Complications associated with cardiovascular implantable electronic devices may necessitate device and lead removal. An open approach to removal may be electively chosen in cases with high risk of complications or those requiring additional concomitant cardiac surgery. This study aimed to investigate outcomes of patients who underwent elective open lead extractions (OLE) at two large tertiary care centers. METHODS: The records of 29 patients undergoing elective OLE were analyzed through retrospective chart review. RESULTS: 69 total leads were extracted from 29 patients (77% completely, 23% partially). The average age of the oldest leads was 13.3 ± 11.3 years. Infective endocarditis with severe valvular insufficiency requiring valvular intervention (41%)-an infectious etiology, and tricuspid valve intervention to correct RV lead-related severe TR (38%)-a noninfectious etiology, were the most common reasons for OLE. 38% of the patients had additional co-primary or secondary indications for open extraction, such as CABG and pericardiectomies. The rate of major complications and procedural failure was 3% each (1/29). 30-day survival was 100%, and 1-year survival was 92%. The average length of hospital stay was 15 days and higher among those undergoing OLE for infectious indications. CONCLUSION: Open lead extractions offered a similar clinical success rate (97%) to transvenous extractions in this cohort and may be a viable alternative for those necessitating valvular intervention or when the risk of complications from TLE is considered very high.

Smaller thoracic canal diameters are associated with thoracic radiculopathy and abdominal pain after spinal cord stimulator paddle lead placement.

INTRODUCTION: It is not uncommon for patients to experience postoperative neurologic deficit, thoracic radiculopathy, abdominal pain, or lower extremity paresthesia after the implantation of thoracic spinal cord stimulator (SCS) paddle leads. Smaller thoracic canal diameters have previously been associated with postoperative neurologic deficits. OBJECTIVE: This imaging study examined whether postoperative SCS neurologic complaints other than neurologic deficit may be correlated with thoracic spinal canal diameter. METHODS: Patients who underwent thoracic laminotomy for SCS paddle lead placement between January 2018 and March 2023 were identified. Preoperative thoracic canal diameter was measured on MRI or CT imaging in the sagittal plane from T5/6 to T11/12. The canal diameters of patients with and without new postoperative neurologic complaints were compared. RESULTS: Two hundred forty-six patients underwent thoracic laminotomy for SCS paddle lead placement. Thoracic radiculopathy, abdominal pain, and lower extremity paresthesia occurred in 3.7% (9/246), 2.8% (7/246), and 2.0% (5/246) patients, respectively. The mean canal diameter for patients without neurologic complaint, thoracic radiculopathy, abdominal pain, and lower extremity paresthesia was 13.1 mm, 12.0 mm (p < 0.0001), 12.1 mm (p < 0.01), and 12.8 mm (p = 0.365), respectively. CONCLUSION: A smaller thoracic canal diameter is associated with postoperative thoracic radiculopathy and abdominal pain. We believe that surgical planning to create adequate space for SCS leads is critical in preventing postoperative neurologic complaints of deficit, thoracic radiculopathy, and abdominal pain.

Pre-natal and early life lead exposure and childhood inhibitory control: an item response theory approach to improve measurement precision of inhibitory control.

BACKGROUND: Neurodevelopmental performance tasks are often separately analyzed, even when they tap into a similar construct. This may yield mixed findings for associations of an exposure-neurobehavioral outcome. We develop an item response theory (IRT) approach to integrate multiple task variables together to improve measurement precision of the underlying construct. We apply this approach to create an integrative measure of childhood inhibitory control, and study impacts of pre/post-natal lead exposure. METHODS: Using data from a prospective cohort based in Mexico (N = 533), we created an inhibitory control scale that integrates accuracy and reaction time information from four inhibitory control tasks (Go/NoGo Letter, Go/NoGo Neutral, Go/NoGo Happy, Delis-Kaplan Executive Function System (D-KEFS) Color-Word Interference Test, Condition 3). Using a generalized partial credit item response theory model, we estimated an inhibitory control index for each participant. We then assessed adjusted associations between umbilical cord blood and 4-year lead and childhood inhibitory control. We developed a resampling approach to incorporate error estimates from the inhibitory control variable to confirm the consistency of the lead-inhibitory control associations. We modeled time-varying associations of lead with each inhibitory control measure separately. RESULTS: Participants had a median age of 9 years; 51.4% were males. Umbilical cord blood [-0.06 (95% CI: -0.11, -0.01)] and 4-year lead [-0.07 (95% CI: -0.12, -0.02)] were associated with inhibitory control index at 8-10 years. A resampling approach confirmed that 4-year lead was consistently associated with childhood inhibitory control index. Umbilical cord blood and 4-year lead were each associated with 3 out of 8 measures in separate models. CONCLUSION: This is the first application of IRT in environmental epidemiology to create a latent variable for inhibitory control that integrates accuracy and reaction time information from multiple, related tasks. This framework can be applied to other correlated neurobehavioral assessments or other phenotype data.

Protective effect of 1, 8-cineole (eucalyptol) against lead-induced liver injury by ameliorating oxidative stress and inflammation and modulating TLR4/MyD88/NF-κB signaling.

Objectives: This study was conducted to explore the impact of 1, 8-cineole (eucalyptol) on the biochemical, molecular, and histological changes caused by lead acetate in the liver of adult male Wistar rats. The research also investigated the potential involvement of the TLR4 signaling pathway in this effect. Materials and Methods: Rats were orally administered lead acetate (25 mg/kg-day) for 14 consecutive days and received 1, 8-cineole (100 mg/kg-day) during the same period. Results: 1, 8-cineole prevented an increase in the malondialdehyde level, a decrease in the glutathione level, and a decrease in the activity of superoxide dismutase and glutathione peroxidase enzymes in the liver of rats treated with lead acetate. This monoterpene also prevented an increase in the expression of pro-inflammatory cytokines and significantly reduced the infiltration of inflammatory cells in the liver parenchyma. Additionally, 1, 8-cineole discouraged the increase in toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), and nuclear factor kappa B (NF-κB) expression in the liver and stopped a rise in serum AST and ALT enzymes. Conclusion: 1, 8-cineole can prevent liver damage caused by lead acetate by reducing oxidative stress and inflammation. This hepatoprotection is probably achieved by inhibiting TLR4/MyD88/NF-κB signaling.

A Roadmap for Ferroelectric-Antiferroelectric Phase Transition.

Antiferroelectric materials have shown great potential in electronic devices benefiting from the reversible phase transition between ferroelectric and antiferroelectric phases. Understanding the dipole arrangements and clear phase transition pathways is crucial for design of antiferroelectric materials-based energy storage and conversion devices. However, the specific phase transition details remain largely unclear and even controversial to date. Here, we have grown a series of PbZrO3 on SrTiO3 substrates and elucidated the fine atom structures and phase transition pathways using atomic-resolution transmission electron microscopy. Specifically, a roadmap for ferroelectric to antiferroelectric phase transitions, here with increasing film thickness, is determined as ferroelectric rhombohedral (R3c)-ferroelectric monoclinic (Pc)-ferrielectric orthorhombic (Ima2)-antiferroelectric orthorhombic (Pbam), where Pc and Ima2 phases act as structural bridges. Moreover, the phase transition pathway is strongly related to the synergistic effect of oxygen octahedral tilting and cation displacement. These findings provide an insightful understanding for the theories and related properties of antiferroelectrics.

Health risk assessment and contamination of lead and cadmium levels in sediments of the northwestern Arabian Gulf coast.

This environmental assessment focuses on the coastal sediments of the Al-Khafji area in the Saudi Arabian Gulf, with an analysis of the human health risks posed by lead (Pb) and cadmium (Cd) contamination. Single and integrated indices were used to detect contamination and evaluate these metals' non-carcinogenic and carcinogenic impacts on adults and children through ingestion, dermal contact, and inhalation pathways. Sediment quality guidelines and contamination indices indicated the absence of significant contamination levels. The moderate contamination observed in scattered samples did not imply adverse biological effects due to the presence of these two metals in Al-Khafji sediments. The average values of the chronic daily intake (CDI) for both Pb and Cd were higher in children than adults across all three pathways, with ratios of 9.4, 4.7, and 4.7 folds, respectively. The hazard index (HI) values for Pb and Cd were below 1, confirming that the sediments of Al-Khafji are considered acceptable and safe in terms of these potentially toxic elements (PTEs). The average lifetime cancer risk (LCR) values for Pb and Cd were higher in children compared to adults, with ratios of 9.3 and 9.4 folds, respectively. However, all detected LCR levels do not represent a potential carcinogenic health hazard. Nevertheless, a regular monitoring program aimed at detecting early signals of environmental health depletion is recommended.