Carcinogenic Metals Research Articles

Nickel Remediation by Adsorption Technique Achieving the Concept of Zero Residue Level

Nickel is a major threat to the wastewater discharged from industries, where it is used, because it is classified as a carcinogenic heavy metal. Due to the need to treat polluted water with the highest efficiency and lowest cost, the promising adsorption technology using agricultural waste has proven to be an effective solution for treating water pollution with various pollutants. This study is concerned with determining the ability of a household waste to remove nickel from contaminated aqueous solutions by the adsorption method at different operating conditions. Waste tea leaves (WTL), which are discarded in huge quantities annually, showed noticeable nickel removal efficiency at more than 74% at acidity, shaking, concentration, time, temperature, and adsorption dose of 6, 350 rpm, 42 ppm, 120 min, 20°C, and 5.5 g, respectively. Although the adsorbent used had a low surface area of 12.251 m2/g, FTIR test before and after adsorption confirmed the presence of various functional groups capable of efficiently performing the adsorption function. Furthermore, FESEM test showed that the adsorption medium suffered significant changes compared to what it was before treatment with contaminated solutions. The use of toxic adsorption residues in a beneficial way was tested by adding them to concrete mixtures and studying the compressibility performance. The results showed that the additives increased the compressive strength of the concrete by more than double before it reached the failure point. Thus, this investigation confirmed the possibility of achieving the concept of zero residue level through waste management in an eco-friendly manner. Keywords: Adsorption, Concrete additives, Nickel, Waste tea leaves, Zero residue level.

The potential carcinogenicity of orthopaedic implants – a scoping review

BackgroundEvery year, hundreds of thousands of patients receive an orthopaedic or dental implant containing metals such as cobalt, chromium and titanium. Since the European Chemicals Agency (2020) classified pure cobalt metal as a Category 1B carcinogen, manufacturers of products containing ≥ 0.1% of this metal must perform a risk assessment and justify that there are no viable alternatives. The up-classification of cobalt metal to a carcinogen without good evidence that its use in implants is carcinogenic may cause unnecessary concern to the many patients who have, or may require such implants. Although in vitro and animal studies have shown such metals to be carcinogenic, human epidemiological studies have not been definitive. In addition, although many advances have been made in the past few decades with regard to the materials used in implant metals, no recent review of their carcinogenic effects have been published.MethodsThis scoping review aims to summarise epidemiological studies conducted in recent years (from 2010 to present) to outline the carcinogenic effects of orthopaedic metal implants that have been published. This encompasses implants of different materials and surfaces, including metal, polyethylene and ceramic orthopaedic implants, cemented and cementless joint replacement surgeries, and surgical techniques such as resurfacing and total joint replacements that are currently in use and the potential carcinogenicity related to their use. Research papers with various study designs published in the English language were included. Studies were excluded if participants had a prior history of cancer before receiving orthopaedic implants and if they focused solely on the carcinogenicity of metals or materials not related to orthopaedic implants.ResultsA total of 16 studies, encompassing over 700,000 implant patients, were identified through PubMed and have been included in this review. In long term follow-up of up to 17.9 years, no increased risk of all-site cancer was seen in these patients. However, an increase in site-specific cancers, namely prostate, melanoma and haematological cancers have been identified. Specifically, an increase in prostate cancer was identified in three studies.ConclusionBased on the summarised evidence, there is no consistent evidence to show that patients with any type of orthopaedic implant has an increased risk of cancer, although slight (non-statistically significant) increases in prostate cancer was observed and this, in particular, deserves longer-term surveillance.

Assessment of Chemical Composition and Health Implications Associated with PM10 Exposure: A Comparative Study of an Urban Road Intersection and a Wood-Burning Vicinity

The chemical composition and potential health risks linked to human exposure to ambient PM10 particles were assessed at the Winneba highway intersection (WHI) and Apam, a wood-burning neighbourhood in Ghana’s Central Region. PM10 particulates were collected using a Gent sampler equipped with a Gast pump and a stacked filter unit. The sampling was done three times a week continuously from July 2022 to June 2023, for 24 h. A smoke stain reflectometer and an Ag-anode X-ray tube spectrometer were used to analyse the samples for black carbon and elemental contents, respectively. The health hazards associated with trace elements were evaluated using the US EPA health risk assessment model. The study’s findings indicated that the amounts of Cr (250.5 ng/m3) and Ni (358.1 ng/m3) detected at Apam surpassed the US EPA threshold limits, as did the values discovered at the WHI, which were 78.63 and 178.2 ng/m3, respectively. PCA indicated that PM10 particles were produced at WHI by soil dust, vehicle exhaust, brake and tyre wear, and two-stroke engines, whereas biomass burning, soil dust, and vehicle exhaust emissions contributed to PM10 at Apam. The non-carcinogenic risks of children’s exposure to trace metals in PM10 via the three exposure pathways were higher compared to adults. The overall cancer risk values for exposure to carcinogenic trace metals from ingestion and dermal contact were more than 10−4, suggesting high cancer risks: 9.49 × 10−4–5.20 × 10−3 for children and 9.03 × 10−4–5.26 × 10−3 for adults. Reducing PM10 and the health concerns it poses requires the use of clean fuel and the adoption of environmentally friendly transportation.

Machine learning integration with response surface methodology to enhance the removal efficacy of arsenate (V) through sulfur-functionalized mxene coated QPPO/PVA AEM

Arsenic, a poisonous and carcinogenic heavy metal in drinking water, presents severe health risks to humans, including skin lesions, neurological damage, and circulatory disorders. Despite extensive research efforts have been carried out on removing arsenate (As(V)) using membrane technologies, however, there remains a critical need to further enhance membrane removal efficacy to achieve maximum reusability. Thus, to minimize this challenge, herein we explore the impact of S-functionalized Mxene coating over the surface of quaternary ammonium poly (2,6-dimethyl-1,4-phenylene oxide)/polyvinyl alcohol (QPPO/PVA) anion exchange AEM membrane against As(V) removal. To optimize and validate adsorption efficacy, response surface methodology (RSM) study was carried out using a central composite design (CCD) with R2 = 0.995. The significance of these variables was also confirmed by CCD matrix, yielding statistically significant results (p < 0.0001). Adsorption efficacy was further enhanced by employing different machine learning (ML) regression models to finely tune experimental parameters. Among ML models, Random Forest Regression (RFR) has shown highest predictive accuracy (R2 = 0.929, RMSE = 4.57 mg L-1) and identified As(V) concentration as the most influential factor affecting adsorption efficacy. ML-optimization has shown maximum adsorption efficacy at pH (3), contact time (5 min), and As(V) concentration (50 mg L−1). Freundlich isotherm model has shown adsorption capacity of 413 mg/g (R2 = 0.997), while pseudo-second-order kinetic model reflected R2 of 0.989. Thermodynamic assessments (ΔGᵒ, ΔH°, ΔS°) confirmed the process as spontaneous. To the best of our knowledge, this is the first study in which ML is employed to design highly efficient and reliable membranes, providing a novel approach to enhance membrane-based remediation strategies.

Appraisement and categorization of compostable and non-compostable plastic bags using HHXRF spectrophotometer, A study on brands in Islamabad

Plastic bags are polymers usually composed of polypropylene, polyethylene and polystyrene. Rapid development in the industrial sector manufacturing plastic bags is imposing tremendous side effects on human health and the environment. Conventional plastic bags are made from recycled or first use, but authorities restricted lightweight plastic bags (thickness of &lt;50μm) with compostable material. This study examines the degradation of plastic bags collected from the markets of different sectors of Islamabad. Many samples (~100) were gathered from the public market. Using a Hands Held X-Ray Fluorescent (HHXRF) spectrophotometer and the standard approach, the study confirmed the proportions, amounts, and patterns of several heavy metals (additives) utilized in the production of both types of bags. The result showed Titanium (Ti), Copper (Cu) and Calcium (Ca) were used in massive amounts, other carcinogenic metals i.e., Mercury (Hg), Arsenic (Ar), Chromium (Cr), Lead (Pb) and Cadmium (Cd) were also detected. Long term exposure to this metal can disrupt living cells. We concluded that because of the photolytic qualities of the additives used in degradable plastic bags when the linkages of polymers are generated, degradable plastic bags may be more dangerous than non-degradable plastic bags.

Highly efficient remediation of Sb-contaminated mine drainage using nano-calcium peroxide induced co-precipitation treatment

Antimony (Sb) mines provide an important metalloid to support the electronic industry but also leave extensive leakage into the aqueous environment. The toxic and carcinogenic heavy metal Sb from mine drainage constitutes a major source of groundwater and soil contamination, indicating intense demands for the environmental-friendly and cost-effective technology to achieve effective remediation. The emerging nanotechnology represents a new technological prospect. In this study, nano-calcium peroxide (nano-CaO2, 8–24 nm) was successfully fabricated by an optimized pH-regulated chemical precipitation method and was used for the lab-based experiments of nano-remediation, with the Sb-contaminated mine drainage collected on-site from an abandoned mine cavern in the Qingjiagou Antimony Mine, Henan Province, China. It is demonstrated that the specifically prepared nanoscale CaO2 has better solubility and faster reaction rates than the commercial CaO2, resulting in promising effect for the nano-remediation of Sb-contaminated groundwater. 97.8 % of an initial 2.8 mg/L Sb contamination was removed in 5 min under the optimum conditions, consisting of 0.5 mg/mL CaO2, 1.0 mg/mL polymeric ferric sulfate (PFS), an oscillation frequency of 120 rpm and a temperature of 298 K. The batch experiments revealed that the initial pH, oscillation frequency, temperature and illumination, as well as hydro-chemical competing ions (i.e., K+, Na+, Ca2+, Mg2+, Mn2+, SO42−, NO3− and Cl−) of the real groundwater all hardly affected the removal efficiency. However, the existence of HCO3− could lead to an obvious impact on the treatment as it would react with the generated OH.

Dietary Interventions for Cancer Prevention: An Update to ACS International Guidelines.

Cancer, the second leading cause of death worldwide, demands the identification of modifiable risk factors to optimize its prevention. Diet has emerged as a pivotal focus in current research efforts. This literature review aims to enhance the ACS guidelines on diet and cancer by integrating the latest findings and addressing unresolved questions. The methodology involved an advanced PubMed search with specific filters relevant to the research topic. Topics covered include time-restricted diet, diet quality, acid load, counseling, exercise and diet combination, Mediterranean diet, vegetarian and pescetarian diets, weight loss, dairy consumption, coffee and tea, iron, carbohydrates, meat, fruits and vegetables, heavy metals, micronutrients, and phytoestrogens. The review highlights the benefits of the Mediterranean diet in reducing cancer risk. Adherence to overnight fasting or carbohydrate consumption may contribute to cancer prevention, but excessive fasting may harm patients' quality of life. A vegetarian/pescetarian diet is associated with lower risks of general and colorectal cancer compared to a carnivorous diet. High heme and total iron intake are linked to increased lung cancer risk, while phytoestrogen intake is associated with reduced risk. Coffee and tea have a neutral impact on cancer risk. Finally, the roles of several preventive micronutrients and carcinogenic heavy metals are discussed.

Trace elements determination and health risk assessment of groundwater sources in Kumasi Metropolis, Ghana.

Trace element (TEs) contamination in groundwater is a key factor for health risk assessment and one of the environmental challenges linked with Ghana's sustainable development. This study aims to investigate TE concentrations in groundwater used for drinking and domestic purposes and their potential health risk in the Kumasi Metropolis using multivariate statistics. In the study, 23 groundwater samples were analyzed for 32 TEs using Perkin Elmer Nexion 2000 Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Levels of TEs recorded in the study were in order of Na > Si > Ca > K > Mg > S > Ba > Cu > Zn > Al > Sr > Li > Mn > P > Fe > B > Pb > Ni > Co > Bi > Se > Sb > Cr > As > Ti > Be > V > U > C d > T l > Mo > Hg. The study revealed that the concentration of trace and toxic elements like Al, Cu, and Pb exceeded their corresponding WHO permissible standards. Hazard index (HI) values and total likely cancer risk (TLCR) values for non-carcinogenic and carcinogenic health risks indicate that 91.3% of the total sampling sites presented health concerns to adults and children. The mean TLCR values associated with exposure to carcinogenic metals via ingestion of groundwater samples were estimated to be 2.09 × 10-4 and 4.44 × 10-4 for adults and children respectively. Exposure through the ingestion pathway was found to be more risky compared to dermal contacts. Children are particularly vulnerable to these health hazards. Pearson correlation (PC) matrix, principal component analysis (PCA), and hierarchical cluster analysis (HCA) suggested that sources of TEs in the groundwater are attributed to both anthropogenic and geogenic factors.

Synchrotron induced X-ray fluorescence spectroscopy reveals heavy metal translocation in sludge amended soil-plant systems: assessment of ecological and health risks.

The use of composted sludge from sewage treatment plants as a soil amendment is a common practice of recycling nutrients like organic carbon, nitrogen, and phosphorus. The sewage generated in larger cities of developing countries is often contaminated with various heavy metals (HMs) that ultimately end up in composted sludge. Thus, using such composted sludge is likely to pose ecological and human health risks. Hence, the knowledge of HM translocation in sludge-soil-plant systems is of vital importance. The present study was aimed at investigating the HM translocation in sludge-soil-plant system. The HM translocation was measured using synchrotron radiation-induced x-ray fluorescence spectrometry and atomic absorption spectroscopic techniques. The results indicated high HM mobility (up to 2628.5mgkg-1) from sludge to spinach plant. The metal accumulation (mgkg-1) ranged in the order-Fe (950.55-2628.5) > Zn (20.11-172.13) > Cu (13.86-136.17) > Mn (2.13-34.67) > Cd (0.11-31.17) > Pb (1.50-30.16) > Co (0.18-9.85) As (0.02-7.80) > Cr (0.01-5.69). This observed accumulation depended on the volume of sewage being treated in the sewage treatment plant (STP) and varied in the order control < (8 MLD Bhagwanpur, STP 1) < (80 MLD Dinapur, STP2) < (140 MLD Dinapur, STP3) hence the HM load coming into STPs. The metal transfer factor, bioconcentration factor, and translocation factor values also correlated with the abundance of Fe, Cu, Pb, Cd, and Zn in spinach root and shoot compartments. The carcinogenic risk for heavy metal carcinogens like As, Cd, Cr, and Pb revealed children being more prone to cancer upon spinach consumption. Hence, it is necessary to assess the heavy metals present in the sludge prior to its application in agricultural fields.

Two-dimensional MXene and molybdenum disulphide for the removal of hexavalent chromium from water: A comparative study

Chromium is a carcinogenic heavy metal that accumulates in plant and animal bodies. New materials for efficient removal of chromium from water bodies are in high demand. MXene was synthesized from MAX phase by using ammonium fluoride as an etching agent while molybdenum disulphide was synthesized by hydrothermal method. The pseudo-second order kinetic model described the adsorption of hexavalent chromium on MXene and molybdenum disulphide whereas the Freundlich Isotherm model best fitted for Mxene, and Langmuir Isotherm model was more suitable in case of molybdenum disulphide. The adsorption capacity obtained by MXene for hexavalent chromium was 59.8 mg/g (At Dosage = 1 g/L, T = 298 K, Time = 9 h, pH = 2, Co = 30 mg/L) and 113.7 mg/g in case of molybdenum disulphide (At Dosage = 0.5 g/L, T = 298 K, Time = 1.5 h, pH = 2, Co = 30 mg/L). Thermodynamic investigations showed that the process was endothermic and spontaneous. The coexisting ions showed a decrease in removal percentage up to 70 % and 79 % in case of MXene and molybdenum disulphide, respectively, after fifth cycle. It can be inferred that these developed materials have the advantages of simplicity for reducing heavy metal pollution.

Green synthesis of Carbonized Chitosan-Fe3O4-SiO2 nano-composite for adsorption of heavy metals from aqueous solutions

Water pollution with heavy metals owing to industrial and agricultural activities have become a critical dilemma to humans, plants as well as the marine environment. Therefore, it is of great importance that the carcinogenic heavy metals present in wastewater to be eliminated through designing treatment technologies that can remove multiple pollutants. A novel green magnetic nano-composite called (Carbonized Chitosan-Fe3O4-SiO2) was synthesized using Co-precipitation method to adsorb a mixture of heavy metal ions included; cobalt (Co2+), nickel (Ni2+) and copper (Cu2+) ions from aqueous solutions. The novelty of this study was the synthesis of a new nano-composite which was green with magnetic properties to be more sustainable and environmentally friendly. Its magnetic properties made it separated easily from solutions after accomplishment of the adsorption process using a magnet. Extended Freundlich isotherm was the best fitted model with maximum adsorption capacity of the metal ions mixture 2908.92 mg/g. Different experimental parameters have been studied included the initial concentration for a mixture of nickel, cobalt and copper metal ions (0.05–0.1 molar), dosage of adsorbent (0.5–3.5 g/L) and contact time (6–90 min) to investigate their changing effect on the removal percents of the heavy metal ions mixture from aqueous solutions. The experimental adsorption percent of cobalt ion ranged from 1.58 to 64.28%, nickel ion adsorption percent ranged from 10.68 to 94.12% and copper ion adsorption percent ranged from 4.41 to 76.23% at pH = 9 were based on the combination of the adsorption process parameters.

Comprehensive recovery of valuable metals from spent LiCoO2 cathode material by a method of NH4HSO4 roasting- (NH₄)₂S leaching

With the retirement of rechargeable lithium-ion batteries (LIBs) entering peak period, the recycling of LiCoO2 has become a hot topic. The spent LiCoO2 batteries are rich in carcinogenic metal Co and high-value metal Li, so they are needed to be recovered in time before causing serious environmental pollution and resource waste. Thus, a clean and efficient process is proposed for the comprehensive recovery of Li, Co, and Mn from the spent LiCoO2 cathode material. It is an integrated pyro-hydrometallurgical process, mainly consisting of sulfation roasting with NH4HSO4 and selective sulfurizing leaching with (NH4)2S solution. Using low melting point ammonium salt as roasting auxiliary, 99.7 %, 99.1 %, and 99.8 % of Li, Co, and Mn in the spent LiCoO2 powder can be converted into sulfate when roasting under 400 ℃ for 75 min. Then 99.5 % of Li in the sulfation roasting product can be selectively leached with an aqueous (NH4)2S solution, which is also a precipitator for Co, Mn, and impurity Al. In addition, 96.4 % of Co and 96.0 % of Mn in the sulfurized precipitate can be separated with impurity elements Al and C via oxidation roasting–water leaching process. Compared to traditional recycling, this method can achieve a higher Li leaching rate at a low roasting temperature, and the recovery of Co and Mn can be realized without adding any acid/base reagents or impurity cations. More importantly, the circulation of NH3/NH4+ and S element in the recycling system has been taken into account, making it an environmental-friendly and economical process. In this study, the sulfation reduction roasting and selective sulfurizing leaching mechanisms were both revealed in details, and the behavior of the valuable elements was also elucidated.

Absence of lung tumor promotion with reduced tumor size in mice after inhalation of copper welding fumes.

Welding fumes are a Group 1 (carcinogenic to humans) carcinogen as classified by the International Agency for Research on Cancer. The process of welding creates inhalable fumes rich in iron (Fe) that may also contain known carcinogenic metals such as chromium (Cr) and nickel (Ni). Epidemiological evidence has shown that both mild steel (Fe-rich) and stainless steel (Fe-rich + Cr + Ni) welding fume exposure increases lung cancer risk, and experimental animal data support these findings. Copper-nickel (CuNi) welding processes have not been investigated in the context of lung cancer. Cu is intriguing, however, given the role of Cu in carcinogenesis and cancer therapeutics. This study examines the potential for a CuNi fume to induce mechanistic key characteristics of carcinogenesis in vitro and to promote lung tumorigenesis, using a two-stage mouse bioassay, in vivo. Male A/J mice, initiated with 3-methylcholanthrene (MCA; 10 µg/g), were exposed to CuNi fumes or air by whole-body inhalation for 9 weeks (low deposition-LD and high deposition-HD) and then sacrificed at 30 weeks. In BEAS-2B cells, the CuNi fume-induced micronuclei and caused DNA damage as measured by γ-H2AX. The fume exhibited high reactivity and a dose-response in cytotoxicity and oxidative stress. In vivo, MCA/CuNi HD and LD significantly decreased lung tumor size and adenomas. MCA/CuNi HD exposure significantly decreased gross-evaluated tumor number. In summary, the CuNi fume in vitro exhibited characteristics of a carcinogen, but in vivo, the exposure resulted in smaller tumors, fewer adenomas, less hyperplasia severity, and with HD exposure, less overall lung lesions/tumors.

Trade-off between sulfidated zero-valent iron reactivity and air stability: Regulation of iron sulfides by ammonium dihydrogen phosphate

The reactivity and stability of zero-valent iron (ZVI) and sulfidated zero-valent iron (S-ZVI) are inherently contradictory. Iron sulfides (FeSX) on the S-ZVI surface play multiple roles, including electrostatic adsorption and catalyzing reduction. We proposed to balance the reactivity and air stability of S-ZVI by regulating FeSX. Benefiting from the superior coordination and accelerate electron transport capabilities of phosphate, herein, eco-friendly ammonium dihydrogen phosphate (ADP) was employed to synthesize N, P, and S-incorporated ZVI (NPS-ZVI) and regulate the FeSX. Raman, FTIR, XPS, and density functional theory (DFT) calculations were combined to reveal that HPO42- acts as the main P species on the Fe surface. The superior reactivity of NPS-ZVI was quantified by kobs, kSA, and kM of Cr(VI), which were 210.77, 27.44, and 211.17-fold than ZVI, respectively. NPS-ZVI demonstrated excellent reusability, with no risk of secondary pollution. Critically, NPS-ZVI could effectively maintain FeSX stability under the combination of diffusion limitation and surface protection mechanisms of ADP. The superior reactivity of NPS-ZVI was attributed to the fact that ADP maintains FeSX stability and accelerates electron transport. This study provides a novel strategy in balancing the reactivity and air stability of S-ZVI and offers theoretical support for material modification.

PM10-bound trace elements in pan-European urban atmosphere

Although many studies have discussed the impact of Europe's air quality, very limited research focused on the detailed phenomenology of ambient trace elements (TEs) in PM10 in urban atmosphere. This study compiled long-term (2013–2022) measurements of speciation of ambient urban PM10 from 55 sites of 7 countries (Switzerland, Spain, France, Greece, Italy, Portugal, UK), aiming to elucidate the phenomenology of 20 TEs in PM10 in urban Europe. The monitoring sites comprised urban background (UB, n = 26), traffic (TR, n = 10), industrial (IN, n = 5), suburban background (SUB, n = 7), and rural background (RB, n = 7) types. The sampling campaigns were conducted using standardized protocols to ensure data comparability. In each country, PM10 samples were collected over a fixed period using high-volume air samplers. The analysis encompassed the spatio-temporal distribution of TEs, and relationships between TEs at each site. Results indicated an annual average for the sum of 20 TEs of 90 ± 65 ng/m3, with TR and IN sites exhibiting the highest concentrations (130 ± 66 and 131 ± 80 ng/m3, respectively). Seasonal variability in TEs concentrations, influenced by emission sources and meteorology, revealed significant differences (p < 0.05) across all monitoring sites. Estimation of TE concentrations highlighted distinct ratios between non-carcinogenic and carcinogenic metals, with Zn (40 ± 49 ng/m3), Ti (21 ± 29 ng/m3), and Cu (23 ± 35 ng/m3) dominating non-carcinogenic TEs, while Cr (5 ± 7 ng/m3), and Ni (2 ± 6 ng/m3) were prominent among carcinogenic ones. Correlations between TEs across diverse locations and seasons varied, in agreement with differences in emission sources and meteorological conditions. This study provides valuable insights into TEs in pan-European urban atmosphere, contributing to a comprehensive dataset for future environmental protection policies.

Development of a surfactant-assisted lanthanum anchored hydroxyapatite@polyaniline hybrid composite for the elimination of chromium ions from aqueous solution

The predominant cause of the global clean water deficit is water contamination caused by heavy metals discharged from various industrial effluents. Innovating low-cost adsorbents that can eliminate heavy metals from polluted water is essential to address this challenge. Human health can be negatively impacted by water contamination caused by the increased levels of carcinogenic heavy metals, such as chromium (Cr), found in wastewater. The main goal of this research is to remove chromium ions from an aqueous environment by utilizing the surfactant-assisted lanthanum anchored hydroxyapatite@polyaniline (CTAB-LaHAp@PANI) hybrid composite. Various analytical techniques including FTIR, XRD, SEM, EDX, TEM, TGA, and XPS analysis were utilized for the characterization of the prepared adsorbents. Different influencing factors such as contact time, solution pH, adsorbent dosage, and initial chromium concentration were systematically optimized through the batch method to achieve maximum removal efficiency of the CTAB-LaHAp@PANI hybrid composite. Remarkably, the CTAB-LaHAp@PANI demonstrated a maximal adsorption capacity of 98.2 mg/g, with an optimal contact time of 120 min at pH 3. The isotherm and kinetic analyses indicated that chromium adsorption onto the CTAB-LaHAp@PANI hybrid composite followed the Langmuir and pseudo-second-order kinetic models, supported by high correlation coefficient values. Moreover, the possible removal mechanism of chromium ions on the prepared hybrid composite was explained based on the results obtained from various analytical techniques. The as-prepared CTAB-LaHAp@PANI hybrid composite demonstrates a superior adsorption capacity, exceptional water stability, cost-effectiveness, and various other characteristics that render it an attractive choice for removing chromium ions from the aqueous phase.

Heavy-metal associated breast cancer and colorectal cancer hot spots and their demographic and socioeconomic characteristics.

Cancer registries offer an avenue to identify cancer clusters across large populations and efficiently examine potential environmental harms affecting cancer. The role of known metal carcinogens (i.e., cadmium, arsenic, nickel, chromium(VI)) in breast and colorectal carcinogenesis is largely unknown. Historically marginalized communities are disproportionately exposed to metals, which could explain cancer disparities. We examined area-based metal exposures and odds of residing in breast and colorectal cancer hotspots utilizing state tumor registry data and described the characteristics of those living in heavy metal-associated cancer hotspots. Breast and colorectal cancer hotspots were mapped across Kentucky, and area-based ambient metal exposure to cadmium, arsenic, nickel, and chromium(VI) were extracted from the 2014 National Air Toxics Assessment for Kentucky census tracts.Among colorectal cancer (n = 56,598) and female breast cancer (n = 77,637) diagnoses in Kentucky, we used logistic regression models to estimate Odds Ratios (ORs) and 95% Confidence Intervals to examine the association between ambient metal concentrations and odds of residing in cancer hotspots, independent of individual-level and neighborhood risk factors. Higher ambient metal exposures were associated with higher odds of residing in breast and colorectal cancer hotspots. Populations in breast and colorectal cancer hotspots were disproportionately Black and had markers of lower socioeconomic status. Furthermore, adjusting for age, race, tobacco and neighborhood factors did not significantly change cancer hotspot ORs for ambient metal exposures analyzed. Ambient metal exposures contribute to higher cancer rates in certain geographic areas that are largely composed of marginalized populations. Individual-level assessments of metal exposures and cancer disparities are needed.

Characterization of Wildland Firefighters' Exposure to Coarse, Fine, and Ultrafine Particles; Polycyclic Aromatic Hydrocarbons; and Metal(loid)s, and Estimation of Associated Health Risks.

Firefighters' occupational activity causes cancer, and the characterization of exposure during firefighting activities remains limited. This work characterizes, for the first time, firefighters' exposure to (coarse/fine/ultrafine) particulate matter (PM) bound polycyclic aromatic hydrocarbons (PAHs) and metal(loid)s during prescribed fires, Fire 1 and Fire 2 (210 min). An impactor collected 14 PM fractions, the PM levels were determined by gravimetry, and the PM-bound PAHs and metal(loid)s were determined by chromatographic and spectroscopic methodologies, respectively. Firefighters were exposed to a total PM level of 1408.3 and 342.5 µg/m3 in Fire 1 and Fire 2, respectively; fine/ultrafine PM represented more than 90% of total PM. Total PM-bound PAHs (3260.2 ng/m3 in Fire 1; 412.1 ng/m3 in Fire 2) and metal(loid)s (660.8 ng/m3 versus 262.2 ng/m3), distributed between fine/ultrafine PM, contained 4.57-24.5% and 11.7-12.6% of (possible/probable) carcinogenic PAHs and metal(loid)s, respectively. Firefighters' exposure to PM, PAHs, and metal(loid)s were below available occupational limits. The estimated carcinogenic risks associated with the inhalation of PM-bound PAHs (3.78 × 10-9 - 1.74 × 10-6) and metal(loid)s (1.50 × 10-2 - 2.37 × 10-2) were, respectively, below and 150-237 times higher than the acceptable risk level defined by the USEPA during 210 min of firefighting activity and assuming a 40-year career as a firefighter. Additional studies need to (1) explore exposure to (coarse/fine/ultrafine) PM, (2) assess health risks, (3) identify intervention needs, and (4) support regulatory agencies recommending mitigation procedures to reduce the impact of fire effluents on firefighters.

Portable smartphone-based RecJf exonuclease-modulated enhanced ratiometric fluorescence bioplatform for rapid visual detection of As3+

Arsenite (As3+), a highly carcinogenic heavy metal ion and widely distributed in nature, can have serious health implications even with minimal exposure. Herein, a portable smartphone device-based ratiometric fluorescence platform was established for sensitive detection of As3+. The work relied on the use of metal-organic framework-tagged cDNA (PCN-224-cDNA), with high adsorption capability and fluorescence properties, as an internal reference to quench the fluorescence of FAM-anchored aptamer (FAM-Apt) via hybridization. In the presence of As3+, FAM-Apt specifically bound to As3+ leading to conformational changes, which detached from the PCN-224-cDNA surface. Interestingly, a smartphone-based readout equipment engineered using a 3D-printed hardware device administered the portable detection of As3+. The limit of detection (LOD) for the proposed ratiometric biosensor was calculated to be 0.021 ng/mL, significantly below WHO's safety threshold. Hence, it demonstrates significant potential for large-scale screening of As3+ residues in food and the environment.

Isolation of Multidrug-Resistant Bacteria from Raw Hides, Salted Hides, and Tannery Wastewater and Their Heavy Metal (Cr) Tolerance

Numerous leather products are created from cattle hides and skins. However, the processing of these products can release toxic heavy metals, including chromium into the environment, leading to health hazards and environmental pollution. This study aims to isolate and identify multidrug-resistant bacteria from rawhide, salted hides, and tanneries in different areas of the Savar region in Dhaka City, Bangladesh. The secondary objective is to determine the heavy metal tolerance and Minimum Inhibitory Concentration (MIC) of Cr against all isolated bacteria. The study found 206 bacterial isolates from three areas: Polashbari Kathaltola, Polashbari Bazar, and Savar Hemaythpur. Rawhide yielded 100 (48.54%) bacterial isolates, salted hide yielded 80(38.83%) isolates, and tannery wastewater yielded only 26 (12.62%) isolates. Further, Bacillus spp. (60) was the most common isolated bacteria. The other identified bacteria were Pseudomonas spp. (46), Staphylococcus spp. (40), Proteus spp. (40), and Escherichia coli (20). The isolated strains showed multidrug resistance, with Staphylococcus spp. Being highly resistant to Erythromycin (100%), followed by Trimethoprim (95%) and Tetracycline (88%). Pseudomonas spp. Were highly resistant to Azithromycin (100%) and Gentamycin (100%). The MIC and the MIC breakpoint determined the screening and evaluation of Cr tolerance against bacteria, and among the isolated bacterial isolates, Bacillus spp. showed a MIC breakpoint of 600 ppm (11.52mM) for Cr tolerance. The isolated heavy metal-resistant bacteria are useful in the bioremediation process and can aid in recovering and removing heavy metals from environmental effluents, thus preventing adverse effects on humans and animals. The government and leather companies should take legal responsibility for proper leather processing to ensure a preventative approach for safe public health. Otherwise, carcinogenic heavy metals can cause cancer in humans.