Toxic heavy metal ions contamination in water and their sustainable reduction by eco-friendly methods: isotherms, thermodynamics and kinetics study.

Heavy metal ions can be introduced into the water through several point and non-point sources including leather industry, coal mining, agriculture activity and domestic waste. Regrettably, these toxic heavy metals may pose a threat to both humans and animals, particularly when they infiltrate water and soil. Heavy metal poisoning can lead to many health complications, such as liver and renal dysfunction, dermatological difficulties, and potentially even malignancies. To mitigate the risk of heavy metal ion exposure to humans and animals, it is imperative to extract them from places that have been polluted. Several conventional methods such as ion exchange, reverse osmosis, ultrafiltration, membrane filtration and chemical precipitation have been used for the removal of heavy metal ions. However, these methods have high operation costs and generate secondary pollutants during water treatment. Biosorption is an alternative approach to eliminating heavy metals from water that involves employing eco-friendly and cost-effective biomass. This review is focused on the heavy metal ions contamination in the water, biosorption methods for heavy metal removal and mathematical modeling to explain the behaviour of heavy metal adsorption. This review can be helpful to the researchers to design wastewater treatment plants for sustainable wastewater treatment.

Evaluation of biotoxins and toxic metal risks in mussels from the Sea of Marmara following marine mucilage.

The mucilage phenomenon observed in the Sea of Marmara in 2021, has raised public concern about seafood safety. Mediterranean mussels serve as a vehicle in food chain, enabling the transfer of pollutants. Farmed and wild mussels were collected from 4 different stations throughout the fishing season. Biotoxins causing amnesic, paralytic, or diarrhetic shellfish poisonings (ASP, PSP, or DSP) were examined during monthly samplings. Potential health risks posed by cadmium, lead and arsenic were assessed. Health risks were evaluated considering 150 g/week mussel consumption, accounting for the different age groups of consumers (50, 60, 70 kg). Estimated Weekly Intake calculations of metals were determined to be lower than Provisional Tolerable Weekly Intake at all age groups throughout the sampling period in all stations. Target Hazard QuotientCd of mussels captured from Istanbul Strait was always determined <1, while it was equal to 1 for 50 kg individuals in Gelibolu samples. All THQAs were >1. Target carcinogenic Risk was evaluated for Pb and iAs, which were found to be negligible and acceptable, respectively. No biotoxins responsible for ASP, PSP, or DSP were detected. Hg levels were under detectable limits. Excluding Cd, the results did not reveal any risks associated with mussel consumption during mucilage.

Characterization and childhood exposure assessment of toxic heavy metals in household dust under true living conditions from 10 China cities.

Health hazards caused by metal exposure in household dust are concerning environmental health problems. Exposure to toxic metals in household dust imposes unclear but solid health risks, especially for children. In this multicenter cross-sectional study, a total of 250 household dust samples were collected from ten stratified cities in China (Panjin, Shijiazhuang, Qingdao, Lanzhou, Luoyang, Ningbo, Xi'an, Wuxi, Mianyang, Shenzhen) between April 2018 and March 2019. Questionnaire was conducted to gather information on individuals' living environment and health status in real-life situations. Multivariate logistic regression and principal component analysis were conducted to identify risk factors and determine the sources of metals in household dust. The median concentration of five metals in household dust from 10 cities ranged from 0.03 to 73.18 µg/g. Among the five heavy metals, only chromium in household dust of Mianyang was observed significantly both higher in the cold season and from the downwind households. Mercury, cadmium, and chromium were higher in the third-tier cities, with levels of 0.08, 0.30 and 97.28 µg/g, respectively. There were two sources with a contribution rate of 38.3 % and 25.8 %, respectively. Potential risk factors for increased metal concentration include long residence time, close to the motorway, decoration within five years, and purchase of new furniture within one year. Under both moderate and high exposure scenarios, chromium showed the highest level of exposure with 6.77 × 10-4 and 2.28 × 10-3 mg·kg-1·d-1, and arsenic imposed the highest lifetime carcinogenic risk at 1.67 × 10-4 and 3.17 × 10-4, respectively. The finding highlighted the priority to minimize childhood exposure of arsenic from household dust.

Mechanism and impact of heavy metal-aluminum (Al) toxicity on male reproduction: Therapeutic approaches with some phytochemicals.

Heavy metals are ubiquitous environmental toxicants that have been known to have a serious effect on human and animal health. Aluminum (Al) is a widely distributed metal in nature. Al exposure has a detrimental impact on human fertility. This review focused on Al-induced male reproductive toxicity and the potential therapeutic approaches with some phytochemicals. Data from the literature showed that Al exposure is accompanied by a drastic decline in blood levels of FSH, LH, and testosterone, reduced sperm count, and affected sperm quality. Al exposure at high levels can cause oxidative stress by increasing ROS and RNS production, mediated mainly by downregulating Nrf2 signaling. Moreover, several investigations demonstrated that Al exposure evoked inflammation, evidenced by increased TNF-α and IL-6 levels. Additionally, substantial evidence concluded the key role of apoptosis in Al-induced testicular toxicity mediated by upregulating caspase-3 and downregulating Bcl2 protein. The damaging effects of Al on mitochondrial bioenergetics are thought to be due to the excessive generation of free radicals. This review helps to clarify the main mechanism involved in Al-associated testicular intoxication and the treatment strategy to attenuate the notable harmful effects on the male reproductive system. It will encourage clinical efforts to target the pathway involved in Al-associated testicular intoxication.

Assessment of human exposure to cadmium and its nephrotoxicity in the Chinese population.

BACKGROUND: Cadmium (Cd) is a toxic heavy metal that widely detected in environment and accumulated in kidney, posing a great threat to human health. However, there is a lack of systematic investigation of exposure profile and association of Cd exposure with renal function in the Chinese population. METHODS: Related articles were searched from PubMed, Web of Science, China National Knowledge Internet, and Wanfang to construct an aggregate exposure pathway (AEP) framework for Cd and to explore the correlation between Cd and renal function using random effects models. RESULTS: A total of 220 articles were included in this study, among which 215 investigated human exposure and 12 investigated the association of Cd with renal outcomes. The AEP framework showed that 96.5 % and 62.5 % of total Cd intake were attributed to dietary intake in nonsmokers and smokers, respectively. And 35.2 % originated from cigarette smoke inhalation in smokers. In human body, Cd was detected in blood, urine, placenta, etc. Although the concentrations of Cd in blood and urine from subjects living in polluted areas showed a sharp downward trend since the early 21st century, higher concentration of Cd in the environment and human body in polluted areas was found. Kidney was the target organ. The level of blood Cd was positively associated with urinary ß2-microglobulin [ß2-MG, r (95 % CI) = 0.12 (0.05, 0.19)], albumin [0.13 (0.06, 0.20)], and retinol-binding protein [RBP, 0.14 (0.03, 0.24)]. Elevated urinary Cd was correlated with increases in ß2-MG [0.22 (0.15, 0.29)], albumin [0.23 (0.16, 0.29)], N-acetyl-ß-d-glucosaminidase [NAG, 0.33 (0.22, 0.44)], and RBP [0.22 (0.14, 0.30)]. CONCLUSIONS: Foods and cigarette smoke were two major ways for Cd intake, and Cd induced renal injury in the Chinese population. This study enhanced the understanding of human exposure and nephrotoxicity of Cd, and emphasized the need for controlling Cd level in polluted areas.

Potentially toxic metals in irrigation water, soil, and vegetables and their health risks using Monte Carlo models.

Food safety has become a serious global concern because of the accumulation of potentially toxic metals (PTMs) in crops cultivated on contaminated agricultural soils. Amongst these toxic elements, arsenic (As), cadmium (Cd), chromium (Cr), and lead (Pb) receive worldwide attention because of their ability to cause deleterious health effects. Thus, an assessment of these toxic metals in the soils, irrigation waters, and the most widely consumed vegetables in Nigeria; Spinach (Amaranthushybridus), and Cabbage (Brassica oleracea) was evaluated using inductively coupled plasma-optical emission spectroscopy (ICP-OES). The mean concentration (measured in mg kg-1) of the PTMs in the soils was in the sequence Cr (81.77) > Pb(19.91) > As(13.23) > Cd(3.25), exceeding the WHO recommended values in all cases. This contamination was corroborated by the pollution evaluation indices. The concentrations (measured in mg l-1) of the PTMs in the irrigation water followed a similar pattern i.e. Cr(1.87) > Pb(1.65) > As(0.85) > Cd(0.20). All the PTMs being studied, were found in the vegetables with Cr (5.37 and 5.88) having the highest concentration, followed by Pb (3.57 and 4.33), and As (1.09 and 1.67), while Cd (0.48 and 1.04) had the lowest concentration (all measured in mg kg-1) for cabbage and spinach, respectively. The concentration of the toxic metals was higher in spinach than in cabbage, which may be due to the redistribution of the greater proportion of the metals above the ground tissue, caused by the bioavailability of metals in the aqueous phase. Expectedly, the hazard index (HI),and carcinogenic risk values of spinach were higher than that of cabbage. This implies that spinach poses potentially higher health risks. Similarly, the Monte Carlo simulation results reveal that the 5th percentile, 95th percentile, and 50th percentile of the cumulative probability of cancer risks due to the consumption of these vegetables exceeds the acceptable range of 1.00E-6 and 1.00E-4. Thus, the probable risk of a cancerous effect is high, and necessary remedial actions are recommended.

Exposure Assessment of Essential and Potentially Toxic Metals in Wheat-Based Sweets for Human Consumption: Multivariate Analysis and Risk Evaluation Studies.

In recent years, there has been a growing concern about the negative impact of unforeseen contaminants such as metals in commonly consumed food items, which pose a threat to human well-being. Therefore, it is of utmost importance to evaluate the levels of these contaminants to guarantee the safe consumption of these food items. The goal of the current research is to determine the levels of essential (EMs: Mg, Ca, Mn, Fe, Co, Cu, and Zn) and potentially toxic metals (PTMs: Al, Cr, Ni, As, Cd, and Pb) in various brands of wheat-based sweets. One hundred samples were collected and analysed via flame atomic absorption spectrometry (FAAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). Also, the current study was to investigate the distribution, correlation, and multivariate analysis of 13 metals (Mg, Ca, Mn, Fe, Co, Cu, Zn, Al, Cr, Ni, As, Cd, and Pb). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used to interpret the metals' association. The concentration (mg/kg) ranges of EMs were, in order, Mg (12.70-65.67), Ca (24.02-209.12), Mn (1.32-9.61), Fe (4.55-111.23), Co (0.32-8.94), Cu (2.12-8.61), and Zn (2.60-19.36), while the concentration (mg/kg) ranges of PTMs were, in order, Al (0.32-0.87), Cr (0.17-5.74), Ni (0.36-1.54), Cd (0.16-0.56), and Pb (0.14-0.92), and As was not detected in any sample under investigation. The HCA data revealed that Co, Al, and Ni form clusters with other metals. Sweets are prepared at high temperatures, and the elevated temperatures can increase the likelihood of Ni and Al leaching from stainless steel. Tolerable dietary intake (TDI) values for Ni were higher than the values established by the European Food Safety Authority (EFSA). The CR value found for the Ni and Cr was at the threshold level of cancer risk, if an amount of 25 g were to be used over a lifetime. In a nutshell, this study highlights the monitoring of EM and PTM levels in wheat-based sweets, and from a food safety perspective, the study is important for consumers of wheat-based sweets.

Evaluating Manganese, Zinc, and Copper Metal Toxicity on SH-SY5Y Cells in Establishing an Idiopathic Parkinson's Disease Model.

Parkinson's disease (PD) is a neurodegenerative condition marked by loss of motor coordination and cognitive impairment. According to global estimates, the worldwide prevalence of PD will likely exceed 12 million cases by 2040. PD is primarily associated with genetic factors, while clinically, cases are attributed to idiopathic factors such as environmental or occupational exposure. The heavy metals linked to PD and other neurodegenerative disorders include copper, manganese, and zinc. Chronic exposure to metals induces elevated oxidative stress and disrupts homeostasis, resulting in neuronal death. These metals are suggested to induce idiopathic PD in the literature. This study measures the effects of lethal concentration at 10% cell death (LC10) and lethal concentration at 50% cell death (LC50) concentrations of copper, manganese, and zinc chlorides on SH-SY5Y cells via markers for dopamine, reactive oxygen species (ROS) generation, DNA damage, and mitochondrial dysfunction after a 24 h exposure. These measurements were compared to a known neurotoxin to induce PD, 100 µM 6-hydroxydopamine (6-ODHA). Between the three metal chlorides, zinc was statistically different in all parameters from all other treatments and induced significant dopaminergic loss, DNA damage, and mitochondrial dysfunction. The LC50 of manganese and copper had the most similar response to 6-ODHA in all parameters, while LC10 of manganese and copper responded most like untreated cells. This study suggests that these metal chlorides respond differently from 6-ODHA and each other, suggesting that idiopathic PD utilizes a different mechanism from the classic PD model.

A metal ion-coordinated DNA probe for sensitive fluorescence detection of metallothionein via a dual nucleic acid amplification strategy.

Sensitively monitoring metallothionein (MT), a heavy metal-binding protein with substantial cysteine content, is of significance for evaluating heavy metal poisoning in both humans and animals. Based on a new metal ion-coordinated DNA probe and the heavy metal ion binding capability of MT, as well as the substantial signal enhancement of the hybridization chain reaction (HCR) and rolling circle amplification (RCA), we demonstrate a highly sensitive fluorescence MT detection assay. MT binds the metal ions in the hairpin structured, metal ion-coordinated DNA probe to switch its hairpin structure into ssDNA, which triggers subsequent RCA reactions and HCRs to open plenty of fluorescently quenched signal hairpins to exhibit drastically amplified fluorescence recovery for assaying MT down to 0.58 nM within a dynamic range of 1-320 nM. In addition, the investigation of low contents of MT in diluted human serum by such an assay has also been verified, indicating its promising application potential for diagnosing heavy metal poisoning.

The effects of temperature on nickel bioaccumulation and toxicity in the freshwater snail Lymnaea stagnalis.

It is well known that temperature can have important effects on the toxicity of metals (and other contaminants) to aquatic organisms. To date, research has mostly focused on thermal effects on acute metal toxicity, and there is a data gap on thermal effects on chronic metal toxicity to sensitive organisms that are particularly relevant to environmental risk assessment. This latter research is especially needed in the context of increased global temperature and heat waves frequency associated with climate change. We investigated temperature effects on chronic nickel (Ni) bioaccumulation and toxicity to the metal-sensitive freshwater snail Lymnaea stagnalis. In the laboratory, we conducted a series of experiments with juvenile snails that were pre-acclimated to different temperatures since their embryonic stage. We found that temperature and nickel separately had strong effects on juvenile growth rate and survival. Rising temperature from 18 to 26 °C had no noticeable effect on Ni-induced growth inhibition and Ni bioaccumulation in juvenile L. stagnalis exposed over 40 days to 0, 30 and 60 µg L-1 of dissolved Ni. These results agreed with estimates of Ni uptake and elimination rates (ku and ke), which were either unaffected by temperature or increased by similar factors from 18 to 26 °C. On the other hand, a temperature increase from 18 to 26 °C appeared to exacerbate Ni lethality to juvenile snails in the 40-day toxicity test. This exacerbation might have been due to a combination of factors, including detrimental changes in metabolically available Ni pools and/or to sensitization of the organism under sub-optimal temperatures. Overall, our study shows that thermal effects on metal chronic toxicity are complex, with effects that can be response-specific and not directly related to metal toxicokinetic.

Monitoring the spatial distribution pattern according to urban land use and health risk assessment on potential toxic metal contamination via street dust in Ankara, Türkiye.

The urbanization processes with growing vehicle numbers cause heavy metal pollution in street dust, and high populations in metropolitan cities are exposed to pollutants. This paper aims to monitor the spatial distribution of heavy metals and evaluate the concentrations via health risk assessment of HMs (Cu, Ni, Cd, Co, Pb, and Zn) that expose the inhabitants to health hazards. According to the results of the current study, sixty street dust samples were applied to the acid digestion technique and quantification by inductively coupled plasma-mass spectrometry (ICP-MS). The spatial distribution of the selected heavy metals in the street dust was investigated using the spatial analysis tool in ArcGIS 10.0 according to population density and land use. In the present study, we used hazard index and cancer risk methods to estimate the public health risk of the pollutants exposed to street dust in Ankara. The concentrations range of the elements in street dust over the study area ranged from 3.34-4.50, 31.69-42.87, 16.09-21.54, 42.85-57.55, 0.00-3.51, and 23.03-30.79, respectively. The overall decreasing order of mean concentration of metals was observed as follows: Pb > Cu > Ni > Co > Cd > Zn. Vehicle traffic and industrial activities seem to be the most critical anthropogenic sources responsible for dust pollution in the study area. The risk assessment of Pb and Ni exposure was the highest, and the hazard index values were 2.42E + 00 and 2.28E + 00 mg/kg/day for children. However, the effect on adults was 2.62E-01 and 2.37E-02 mg/kg/day, followed by inhalation and dermal contact with street dust was almost negligible. The decreasing concentration is modeled spatially along the western development corridor of the city. The risk to public health is high in areas with high densities close to the city center and the main artery.

The role of chemical fractionation in risk assessment of toxic metals: a review.

The identification of highly toxic metals like Cd, Ni, Pb, Cr, Co or Cu in ambient particulate matter (PM) has garnered a lot of interest recently. Exposure to toxic metals, including carcinogenic ones, at levels above recommended limits, can significantly affect human health. Prolonged exposure to even trace amounts of toxic or essential metals can also have negative health impacts. In order to assess significant risks, it is crucial to govern the concentrations of bioavailable/bio-accessible metals that are available in PM. Estimating the total metal concentrations in PM is only an approximation of metal toxicity. This review provides an overview of various procedures for extracting soluble toxic metals from PM and the importance of chemical fractionation in risk assessment. It is observed that the environmental risk indices such as bioavailability index (BI), contamination factor (CF) and risk assessment code (RAC) are specifically influenced by the concentration of these metals in a particular fraction. Additionally, there is compelling evidence that health risks assessed using total metal concentrations may be overestimated, therefore, the metal toxicity assessment is more accurate and more sensitive to the concentration of the bioavailable/bio-accessible fraction than the total metal concentrations. Hence, chemical fractionation of toxic metals can serve as an effective tool for developing environmental protection laws and improving air quality monitoring programs for public health.

Monte Carlo simulation and delayed geochemical hazard revealed the contamination and risk of arsenic in natural water sources.

Due to its ubiquity and carcinogenicity, the geochemical behavior and health risks of arsenic (As) have been a research focus worldwide. A comprehensive investigation was conducted on the contamination and ecological and health risks of As in the Zijiang River (ZR)-a natural water source. The concentration ranges of As were separately 1.36-6.23 µg/L, 11.42-74.53 mg/kg, and 1.26-130.68 µg/L in surface waters (dissolved), sediments, and pore waters. The concentrations of As in the midstream pore waters and sediments were relatively high, which was related to mining, dam interception, and sediment resuspension. The Monte Carlo simulation results showed that the occurrence probability of As contamination and static risk in sediments was low, however, in the midstream, the secondary risk caused by the release of As should be given more consideration. In the sediments, the transformation paths and the dynamic risk of As were explored based on the delayed geochemical hazard model, showing that there was a probability of a potential burst of 26.47% - 55.88% in the sediments of the ZR. Although at the detected surface waters, the total risk of the noncarcinogenicity and carcinogenicity of As were low, overall adults have lower health risks than children, and As exposure in children should be of concern. This study complements the further understanding of the geochemical behavior of arsenic, which can be extended to other toxic metal(loid)s.

Metal(loid) Analysis of Commercial Rice from Malaysia using ICP-MS: Potential Health Risk Evaluation.

Rice is a predominant staple food in many countries. It is a great source of energy but can also accumulate toxic and trace metal(loid)s from the environment and pose serious health hazards to consumers if overdosed. This study aims to determine the concentration of toxic metal(loid)s [arsenic (As), cadmium (Cd), nickel (Ni)] and essential metal(loid)s [iron (Fe), selenium (Se), copper (Cu), chromium (Cr), cobalt (Co)] in various types of commercially available rice (basmati, glutinous, brown, local whites, and fragrant rice) in Malaysia, and to assess the potential human health risk. Rice samples were digested following the USEPA 3050B acid digestion method and the concentrations of metal(loid)s were analyzed using an inductively coupled plasma mass spectrometry (ICP-MS). Mean concentrations (mg/kg as dry weight) of metal(loid)s (n=45) across all rice types were found in the order of Fe (41.37)>Cu (6.51)>Cr (1.91)>Ni (0.38)>As (0.35)>Se (0.07)>Cd (0.03)>Co (0.02). Thirty-three percent and none of the rice samples surpassed, respectively, the FAO/WHO recommended limits of As and Cd. This study revealed that rice could be a primary exposure pathway to toxic metal(loid)s, leading to either noncarcinogenic or carcinogenic health problems. The non-carcinogenic health risk was mainly associated with As which contributed 63% to the hazard index followed by Cr (34%), Cd (2%), and Ni (1%). The carcinogenic risk to adults was high (>10-4) for As, Cr, Cd, and Ni. The cancer risk (CR) for each element was 5 to 8 times higher than the upper limit of cancer risk for an environmental carcinogen (<10-4). The findings from this study could provide the metal(loid)s pollution status of various types of rice which are beneficial to relevant authorities in addressing food safety and security-related issues.

Arbuscular mycorrhizal fungi and nitric oxide alleviate cadmium phytotoxicity by improving internal detoxification mechanisms of corn plants.

Plants develop several external and internal mechanisms to increase their tolerance to heavy metals (HMs) toxicity including cadmium (Cd). Symbiosis with arbuscular mycorrhizae fungi (AMF) is one of the plants' strategies to tolerate HMs toxicity. Nitric oxide (NO), as a signaling molecule, is also involved in physiological responses of plants to various stresses. The present work was conducted as a factorial completely randomized design with three replications to study the effects of Funneliformis mosseae fungi and Sodium nitroprusside (SNP, 100 mM) as a donor of NO alone, in combination (AMF + SNP) on corn plant growth, and internal detoxification mechanisms of Cd toxicity in a Cd-contaminated calcareous soil (0, 25, 50, and 100 mg Cd kg-1). The results showed that under Cd stress, AMF inoculation and/or foliar application of SNP significantly increased plant growth (32% to 103% for shoot and 44% to 84% for root) by decreasing Cd concentration in corn plant tissues (23% to 46% for shoot and 19% to 40% for root). Cd-induced oxidative stress was mitigated by AMF and/or SNP by enhancing the activities of antioxidant enzymes, including superoxide dismutase (SOD) and catalase (CAT), and concentration of non-enzymatic antioxidants such as glutathione (GSH) and phytochelatin (PC). Increasing the tolerance index (TI) and decreasing the transfer factor (TF) in the corn plants treated with AMF and/or SNP, confirm the efficient role of SNP and AMF in stimulating the detoxification mechanisms of Cd within the plant cells, which was more pronounced at the lowest Cd level (25 mg Cd kg-1). In conclusion, symbiotic associations of corn plants with AMF alone or in combination with SNP mitigated the detrimental effect of Cd toxicity in corn grown in Cd-contaminated calcareous soil. The corn's internal detoxification mechanisms lowered the Cd concentration in plant tissue which resulted in the improvement of the corn's growth parameters.

Assessment of lead, cadmium, and mercury levels in the breast milk in Pakistani women.

The concentrations of potentially toxic metals like lead (Pb), cadmium (Cd), and mercury (Hg) in healthy lactating mothers of Lahore city were estimated during 2020-2021 with the help of a flame atomic absorption spectrometer (FAAS). Seventy samples of breast milk were collected from two different age groups, namely, G-1 (25-30 years) and G-2 (31-40 years). The results showed that Cd contents were below the detection limit of the measuring instrument; however, the Pb and Hg contents were detected with great ease. The mean concentrations of Pb and Hg in the G-1 corresponding to the age between 25 and 30 years were observed to be 1.914 ± 0.493 µg/L and 10.432 ± 3.249 µg/L, respectively. For the G-2 with an age limit between 31 and 40 years, the concentrations of Pb and Hg were estimated to be 2.045 ± 0.502 µg/L and 11.527 ± 3.231 µg/L, respectively. The T-test analysis of concentrations of these toxic metals indicated a significant correlation between the content levels of Pb and Hg (p < 0.05). The observed values of toxic metals were significantly more frequent than those suggested by WHO (World Health Organization). An increase in the concentrations of Pb and Hg is directly associated with the location of the target population. As a result, it is turned out that the majority of the lactating woman with significantly high levels of Pb and Hg belongs to industrial areas of Lahore. To avoid such conditions, residential areas must be at larger distances, in addition, to strictly abiding by the environmental policies of the government.

Potentially toxic metals contamination, health risk, and source apportionment in the agricultural soils around industrial areas, Firozabad, Uttar Pradesh, India: a multivariate statistical approach.

Potentially toxic metals (PTMs) contamination in the soil poses a serious danger to people's health by direct or indirect exposure, and generally it occurs by consuming food grown in these soils. The present study assessed the pollution levels and risk to human health upon sustained exposure to PTM concentrations in the area's centuries-old glass industry clusters of the city of Firozabad, Uttar Pradesh, India. Soil sampling (0-15 cm) was done in farmers' fields within a 1 km radius of six industrial clusters. Various environmental (geo-accumulation index, contamination factor, pollution load index, enrichment factor, and ecological risk index) and health risk indices (hazard quotient, carcinogenic risk) were computed to assess the extent of damage caused to the environment and the threat to human health. Results show that the mean concentrations of Cu (33 mg kg-1), Zn (82.5 mg kg-1), and Cr (15.3 mg kg-1) were at safe levels, whereas the levels of Pb, Ni, and Cd exceeded their respective threshold limits. A majority of samples (88%) showed considerable ecological risk due to the co-contamination of these six PTMs. Health risk assessment indicated tolerable cancer and non-cancer risk in both adults and children for all PTMs, except Ni, where adults were exposed to potential threat of cancer. Pearson's correlation study revealed a significant positive correlation between all six metal pairs and conducting principal component analysis (PCA) confirmed the common source of metal pollution. The PC score ranked different sites from highest to lowest according to PTM loads that help to establish the location of the source. Hierarchical cluster analysis grouped different sites into the same cluster based on similarity in PTMs load, i.e., low, medium, and high.

Cadmium induced bioaccumulation, histopathology, gene regulation in fish and its amelioration - A review.

Different anthropogenic activities as well as natural sources contribute enormously towards various heavy metal contaminations in aquatic habitats. Cadmium (Cd) is one of most prevalent and toxic heavy metals with a long half life. Unlike terrestrial animals, exposure of Cd in fishes may happen not only through feeds but also from its habitat water. Bioaccumulation of Cd in fishes occurs in many tissues, but mainly in gill, liver, kidney, skin, and muscle. The concentrations of Cd in fish tissues depend upon the extent and duration of Cd exposure, species and age of fishes, dietary minerals and antioxidant concentrations, and habitat water quality. Specific histopathological observations in liver, kidney, and gill are useful to understand the effects of Cd, which could help to determine the ameliorating methods to be adopted. Exposure of Cd exerts several adverse effects on general growth and development, reproductive processes, osmoregulation, morphological and histological structures, stress tolerance, and endocrine system, mainly due to changes in biological functions induced by differential expressions of several genes related to oxidative stress, apoptosis, inflammation, immunosuppressions, genotoxicity, Cd chelation and carbohydrate metabolism. Chronic biomagnifications of Cd exceeding the permitted level may be harmful not only to the fishes itself but also to humans through food chains. Amelioration of such toxic heavy metal that has been categorized as a potent carcinogenic in humans is of utmost importance. Main modes of amelioration encompas reducing oxidative damages by promoting the antioxidative defenses, decreasing Cd absorption, increasing excretion through excretory system and improving the tolerance of fishes to Cd toxicity. Many amelioration measures such as use of minerals (for example, zinc, calcium, and iron), vitamins (vitamin C, A, and E), different herbs, probiotics and other agents (taurine, bentonite, chitosan, zeolite, and metallothionein) have been explored for their effective roles to reduce Cd bioaccumulation and toxicity symptoms in fishes. The present review discusses bioaccumulation of Cd, histopathological alterations, oxidative stress, synergism-antagonism, and gene regulation in different tissues, and its amelioration measures in fishes.

Toxicogenomic analysis of physiologically important metals: An integrated in silico approach.

Biologically important metals regulate cellular homeostasis in living systems. Anthropogenic exposure to these metals can cause adverse effects, including an increased incidence of diseases in humans such as cancer, lung, and cardiovascular defects. However, the effects of metals and the common genes/signaling pathways involved in metal toxicity have not been elucidated. Hence, the present study used toxicogenomic data mining with the comparative toxicogenomics database to explore the impact of these metals. The metals were categorized into transition, alkali, and alkaline earth. The common genes were identified and subjected to functional enrichment analysis. Further, gene-gene and protein-protein interactions were assessed. Also, the top ten transcription factors and miRNAs that regulate the genes were identified. The phenotypes and diseases that have increased incidence upon alterations of these genes were detected. Overall, we were able to identify IL1B and SOD2 as the common genes, along with the AGE-RAGE signaling pathway in diabetic complications as the common pathway altered. Enriched genes and pathways specific to each metal category were also found. Further, we identified heart failure as the major disease that could have increase in the incidence upon these metals' exposure. In conclusion, exposure to essential metals might cause adverse effects via inflammation and oxidative stress.

Pattern and predictors of death from aluminum and zinc phosphide poisoning using multi-kernel optimized relevance vector machine.

The use of metal phosphides, particularly aluminum phosphide, poses a significant threat to human safety and results in high mortality rates. This study aimed to determine mortality patterns and predictive factors for acute zinc and aluminum phosphide poisoning cases that were admitted to Menoufia University Poison and Dependence Control Center from 2017 to 2021. Statistical analysis revealed that poisoning was more common among females (59.7%), aged between 10 and 20 years, and from rural regions. Most cases were students, and most poisonings were the result of suicidal intentions (78.6%). A new hybrid model named Bayesian Optimization-Relevance Vector Machine (BO-RVM) was proposed to forecast fatal poisoning. The model achieved an overall accuracy of 97%, with high positive predictive value (PPV) and negative predictive value (NPV) values of 100% and 96%, respectively. The sensitivity was 89.3%, while the specificity was 100%. The F1 score was 94.3%, indicating a good balance between precision and recall. These results suggest that the model performs well in identifying both positive and negative cases. Additionally, the BO-RVM model has a fast and accurate processing time of 379.9595 s, making it a promising tool for various applications. The study underscores the need for public health policies to restrict the availability and use of phosphides in Egypt and adopt effective treatment methods for phosphide-poisoned patients. Clinical suspicion, positive silver nitrate test for phosphine, and analysis of cholinesterase levels are useful in diagnosing metal phosphide poisoning, which can cause various symptoms.