Cadmium Exposure and Potential Health Risk from Foods in Contaminated Area, Thailand

Metal(oid) profiling of the common site of osteoporotic fractures with bone microarchitecture correlation analysis: a comparative study of hip fracture patients and healthy individuals

Increased urine and blood concentrations of heavy metals are linked to an elevated hip fracture risk, but studies dedicated to directly measuring metal(oid) concentrations in the femoral neck are limited. We investigated whether individuals with fractures exhibit a different pattern of metal(oid) bioaccumulation in the femoral neck and examined potential correlations between the concentrations of various metal(oid)s in the femoral neck and trabecular microarchitecture. To address these objectives, we collected femoral neck specimens from 23 individuals, namely 11 individuals with a positive history of contralateral hip fracture (9 women and 2 men, mean age 77.7 ± 8.1 years) and 12 individuals without fractures (10 women and 2 men, mean age 79.5 ± 5.6 years). All samples were subject to microcomputed tomography (micro-CT) to evaluate bone microarchitecture and inductively coupled plasma-mass spectrometry to determine tissue concentrations of metal(oid)s. In the fully adjusted model (adjusted for bone volume, age, and calcium tissue concentration), individuals with hip fractures exhibited higher aluminum levels (p = 0.047) and lower vanadium levels (p < 0.001). Individuals who sustained fragility fractures also showed lower BV/TV, Tb.Th, Tb.N, and higher Tb.Sp in the femoral neck trabeculae compared with the control group. Several different metal(oid)s were associated with altered patterns of trabecular microarchitecture. In summary, higher aluminum and lower vanadium concentrations in the trabeculae of the femoral neck provide a potential background for the gradual increase in fracture risk. Correlational analysis revealed an association between exposure to certain metals and deteriorated trabecular microarchitecture; however, larger studies are needed to determine the elements independently affecting bone microarchitecture.

Co-precipitating calcium phosphate as oral detoxification of cadmium

Bone-eating (also known as osteophagia), found in wild animals, is primarily recognized as a means to supplement phosphorus and calcium intake. Herein, we describe a novel function of bone-eating in detoxifying heavy metal ions through the dissolution and co-precipitation of bone minerals as they travel through the gastrointestinal (GI) tract. In this study, cadmium (Cd), a heavy metal ion, served as a toxic model. We demonstrated that hydroxyapatite (HAp), the major calcium phosphate (CaP) in bone, dissolves in the stomach and acts as a co-precipitant in the intestine for Cd detoxification. We compared HAp to a common antidote, activated charcoal (AC), which did not precipitate within the GI tract. In vitro experiments showed that HAp dissolves under acidic conditions and, upon return to a neutral environment, efficiently re-sequesters Cd. Similarly, oral administration of HAp effectively prevented Cd absorption and accumulation, resulting in enhanced Cd excretion in the feces when compared to AC. A co-precipitating CaP in the GI tract could serve as an excellent detoxification system, as it helps prevent the accumulation of toxic substances and aids in developing appropriate strategies to reduce tissue toxicity. Moreover, understanding this detoxification system would be a valuable indicator for designing efficient detoxification materials.

Investigating the role of food pollutants in autism spectrum disorder: a comprehensive analysis of heavy metals, pesticides, and mycotoxins

Food pollutants, including heavy metals, pesticides, and mycotoxins, have been proposed as potential risk factors for autism spectrum disorder (ASD) during pregnancy and early childhood. This paper examines the impact of food pollutants on ASD risk. A systematic search through PubMed, Google Scholar, and Sciverse yielded studies from 1990 to present. Research indicates elevated levels of heavy metals in children with ASD, linking pesticides and toxins to brain development disruptions. Mycotoxins, specifically, show a correlation with ASD and can contaminate food, posing a threat to neurodevelopment. Strategies like choosing organic foods and reducing exposure to toxins may benefit individuals with ASD and those vulnerable to the disorder. Further research is essential to comprehend the food pollutant-ASD relationship and devise effective exposure reduction strategies.

Polyphenolic Composition, Antioxidant Activity, and Cytotoxic Effect of Male Floral Buds from Three Populus Species Growing in the South of Romania

Three poplar species widely distributed in southern Romania were investigated for their chemical composition and bioactivity. Male buds from black poplar (Populus nigra L.), white poplar (Populus alba L.), and Euroamerican hybrid poplar (Populus × euramericana (Dode) Guinier.) were analyzed using HPTLC, HPLC, GC-MS, and spectrophotometric assays. The analysis revealed predominantly polyphenolic compounds, including phenolic acids and flavonoids, secondary metabolites recognized for their antioxidant properties, particularly valuable in alleviating oxidative stress disorders. Heavy metal content was measured using atomic absorption spectroscopy, and antioxidant capacity was assessed through DPPH and FRAP assays alongside a cytotoxicity evaluation. Polyphenolic content ranged from 19.26 to 33.37 mg GAE/g DW and flavonoid content from 2.15 to 4.45 mg RE/g DW. All three species demonstrated notable antioxidant capacity and cytotoxic activity. Hydroethanolic extracts of P. nigra and P. euramericana showed higher antioxidant activity than aqueous extracts, with P. nigra achieving the lowest IC50 value overall, highlighting the influence of solvent choice on antioxidant efficacy. Furthermore, poplar hydroethanolic extracts exhibited concentration-dependent cytotoxicity against fibroblast-like human osteosarcoma MG63 cell lines, with IC50 values of 42.55 µg/mL for P. nigra, 40.87 µg/mL for P. × euramericana, and 132.49 µg/mL for P. alba, underscoring significant interspecies variability in cytotoxic potency. These findings suggest that male floral buds from Romanian poplar species may serve as valuable sources of bioactive compounds with therapeutic potential.

Assessment of polycyclic aromatic hydrocarbons (PAHs) and heavy metal contamination in Shitalakshya River water: ecological and health risk implications

The Shitalakshya River, vital to the Dhaka district, faces severe pollution challenges due to industrial discharges, urban runoff, and other anthropogenic activities. This study investigated the concentration of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in the river water, utilizing GC-MS/MS and ICP-MS techniques. The results revealed a total PAH concentration ranging from 4.97 to 5.87 ng/mL, with 3-ring PAHs being the most prevalent. Heavy metals such as Fe, As, Ni, and Zn were found in significant concentrations, exceeding international standards for drinking water and aquatic life. The ecological risk assessment identified benzo(b)fluoranthene, benzo(k)fluoranthene, and indeno(1,2,3-cd)pyrene as the highest threats to aquatic organisms. Health risk assessments indicated substantial risks from dermal and ingestion exposures, particularly due to arsenic, highlighting potential long-term health implications for local residents. The study underscores the urgent need for comprehensive monitoring, pollution source identification, and stringent regulatory measures to mitigate these risks.

Detrimental effects of cadmium on male infertility: A review

Infertility has become a serious health and socio-economic-psychological problem globally. The harmful role of trace metals in male infertility is recognized but still not sufficiently explained. Herein, a comprehensive review was conducted to elucidate the detrimental role of cadmium (Cd) on male infertility, particularly on infertility with unknown (idiopathic) causes. Peer-reviewed studies from 2000 to 2024 dealing with seminal plasma and blood Cd levels of fertile and infertile men were retrieved were interrogated with regard to strict inclusion/exclusion criteria, and then were thoroughly reviewed and analyzed. Another aim of this review was to indicate the potential effects of Cd on changes in seminogram findings. A median range of seminal plasma Cd levels from 0.2 to 1.5 µg/L can be considered safe for men's fertility. This review strongly implies that Cd levels were notably higher in seminal plasma of infertile cases than controls. The review's data also indicate that exposure to tobacco smoke is a major source of elevated seminal and blood Cd levels in infertile men. Newer research points to the importance of Cd in lower levels from the environment on changes in seminogram findings, primarily count, motility of spermatozoa, and their morphology. Overall, this review implies that seminal plasma Cd levels could be a good indicator of semen quality. However, new, in-depth studies are needed to confirm or reject the causal relationship of Cd with male infertility.

Impact of Chocolate Cadmium on Vulnerable Populations in Serbia

Chocolate is one of the most popular and widely consumed confectionery products. However, elevated cadmium (Cd) content in this commodity threatens food safety and human health. It is crucial to monitor the presence of Cd in chocolate and to evaluate its associated health risks. This study assessed the Cd levels in milk and dark chocolates from the Serbian market (n = 155). Cadmium concentrations varied between 0.010 and 0.29 mg/kg. The obtained values were used to evaluate the hazard quotient (HQ) and cancer risk (CR). The estimated weekly intakes (EWIs) were below the tolerable limits for all samples. However, in some samples, the EWI reached 60.9% and 63.5% of the tolerable limit for toddlers and other children, respectively. No health risk was found based on the HQ. On the other hand, based on CR values, all chocolate products can be classified as posing a moderate risk. The Monte Carlo simulation indicated that toddlers and other children were more exposed to non-carcinogenic risk, whereas vegetarians, adults, pregnant women, and other children were more exposed to cancer risk. Sensitivity analysis indicates that body weight, exposure frequency, and ingestion rate are the most influential factors for non-cancer and cancer health risks.

Foliar application of zinc and selenium regulates cell wall fixation, physiological and gene expression to reduce cadmium accumulation in rice grains

Zinc (Zn) and selenium (Se) are beneficial elements for crops, enhancing crop quality and alleviating heavy metal toxicity. However, there is limited research on the role of foliar Zn and Se in the mechanism of reducing cadmium (Cd) uptake in crops. A field experiment was conducted to investigate the effect on subcellular distribution, leaf antioxidant enzyme activities, and the transcriptional regulation in the process of Cd accumulation of rice grains after foliar applications of Zn, Se, and their mixed solutions (ZnSe). The results show that Zn and ZnSe reduced Cd content in the grains of three different rice (13.9 %-21.8 %/11.9 %-29.5 %) by enhancing the fixation capacity of Cd in the flag leaf by improving the binding efficiency between pectin and Cd in the cell wall. Increased flag leaf antioxidant enzyme activities further mitigated the toxic effects of Cd on rice, while Zn and ZnSe treatments upregulated genes related to metal-binding proteins and antioxidant enzymes and downregulated metal transport genes. This study systematically elucidates the mechanisms by which foliar application of ZnSe alleviates Cd toxicity through the regulation of gene expression and physiological functions, providing a theoretical basis for reducing Cd accumulation in rice and ensuring the safe production of food.

Dietary Risk Assessment of Cadmium Exposure Through Commonly Consumed Foodstuffs in Mexico

Cadmium (Cd) is a toxic heavy metal widely distributed in foodstuffs. In Mexico, few studies have evaluated Cd content in foods. This study aimed to determine Cd concentrations in foodstuffs that are highly consumed and bought in Mexico City to identify foods exceeding the Maximum Level (ML) and to assess the health risks of theoretical Cd intake from a diet following the Mexican Dietary Guidelines. A total of 143 foodstuffs were analyzed by atomic absorption spectrophotometry. Theoretical Cd intake was estimated in portions per week and compared with the Cd Tolerable Weekly Intake (TWI = 2.5 μg/kg per body weight). A total of 68.5% of the foodstuffs had detectable Cd concentrations. Higher concentrations were found in oyster mushrooms (0.575 mg/kg), romaine lettuce (0.335 mg/kg), and cocoa powder (0.289 mg/kg). Food groups with higher mean concentrations were vegetables (0.084 mg/kg) and snacks, sweets, and desserts (0.049 mg/kg). Ancho chili and romaine lettuce exceed the ML. The theoretical Cd intake estimation was 1.80, 2.05, and 3.82 μg/kg per body weight for adults, adolescents, and school-age children, respectively. This theoretical Cd intake represents a health risk only for school children exceeding the TWI by 53.2%. Our study confirms the presence and risk of Cd in Mexican foodstuffs and highlights the importance of monitoring programs.

Metabolomic Analysis and Biochemical Profiling of Cadmium-Induced Metabolic Impairment and Its Amelioration by Resveratrol

Exposure to heavy metals, particularly cadmium (Cd), poses significant health risks because of their toxic effects and potential for bioaccumulation in living organisms. This study examined the biochemical and metabolomic changes induced by Cd exposure in an animal model via advanced liquid chromatography with tandem mass spectrometry (LC-MS/MS) and biochemical assays to reveal significant disruptions in lipid and amino acid metabolism as well as alterations in key metabolic pathways. Cd exposure led to significant weight loss, hyperglycemia, and insulin resistance, indicating its role in metabolic disorders such as diabetes. The accumulation of Cd in the liver and kidneys, identified via ICP-OES, corresponded with elevated levels of liver (ALT, AST) and kidney (BUN, creatinine) biomarkers, suggesting organ-specific toxicity. At the metabolic level, Cd exposure caused the accumulation of lipid metabolites such as ceramides and sphingolipids, which are associated with insulin resistance and broader metabolic impairments. Amino acid metabolism was also significantly disrupted, with increased concentrations of key amino acids such as phenylalanine, tryptophan, and arginine affecting pathways such as the urea cycle and Krebs cycle. These metabolic disturbances are linked to oxidative stress, systemic inflammation, and impaired glucose regulation, as evidenced by elevated CRP and IL-6 levels. The protective effects of resveratrol (RSV) were clearly demonstrated in this study. RSV treatment ameliorated Cd-induced biochemical and metabolic alterations, as shown by improved glycemic control, restored lipid profiles, and normalized amino acid concentrations. Additionally, RSV significantly reduced inflammatory markers and improved liver and kidney function, highlighting its antioxidant properties and potential as a therapeutic agent against Cd toxicity. However, RSV did not significantly reduce Cd accumulation in organs, indicating that its protective effects are related to mitigating oxidative damage and metabolic disruption rather than promoting Cd excretion. This study enhances our understanding of the molecular mechanisms underlying Cd-induced metabolic impairments and highlights the therapeutic potential of RSV in combating Cd toxicity. These findings underscore the need for further research into heavy metal exposure and its mitigation to protect human health, particularly in areas of environmental contamination.

A critical review on heavy metal contamination in aquatic food webs by edible fish species: a special case concerning Bangladesh

Heavy metals (HMs) are ubiquitous in terrestrial and aquatic environments due to unplanned industrial waste discharge, the release of untreated wastewater, and improper mining activities. In particular, the concentrations of HMs are found to be higher in aquatic environments. As a result, the aquatic biota was heavily affected by HM contamination. This critical review aims to understand the sources and toxicity of HMs in commercial fish species, explore their ecological exchange, and examine the related human health challenges in Bangladesh. A modified PRISMA review technique is used in this paper to analyze the current status and research limitations of HM studies in Bangladesh fish species and their toxicity within aquatic food webs. Briefly, we searched several keywords to explore the research trend of HM concentrations and toxicity in fish species. Furthermore, potential toxicity and risk assessment of HMs through the aquatic food chain in Bangladesh were explored. On the other hand, a cross-tabulation approach was used to process the toxicity findings of HMs. Previous studies indicate that fish species can possess comparatively higher HMs than river water due to ecological exchange factors, including bioaccumulation and biotransformation. This review focuses on Bangladesh, highlighting areas for improvements and the need for further study to achieve a transparent understanding of HM deposition in fish species and the sustainable management of aquatic food chain toxicity.

Assessment of heavy metal contamination in groundwater and its implications for dental and public health

Groundwater contamination with heavy metals is a critical environmental issue, especially in regions heavily reliant on groundwater for drinking purpose. These metals can seep into groundwater from soil and rock weathering or through improper disposal of industrial waste and effluents. Access to safe drinking water is essential for maintaining public health. This study aimed to assess heavy metal contamination in groundwater and its implications for dental and public health. The objective of the study was to measure the concentration of the heavy metals in the dentine of extracted tooth of the study population. The study concurrently measured heavy metal concentrations in groundwater and tooth dentine samples, analyzing demographic profiles, heavy metal correlations, and underlying structures using Principal Component Analysis (PCA). The average level of heavy metals in the groundwater samples varied from 9.763 ± 3.362 μg/L for Cd to 3426.204 ± 875.264 μg/L for Fe. The mean concentrations (μg/g) in teeth dentine showed significant variations, with iron (Fe) ranging from 0.149 ± 0.03 μg/g in water purifiers to 4.62 ± 0.578 μg/g in local water sources. Similar variations were observed for other heavy metals across different water sources. Principal component analysis (PCA) revealed seven principal components, with the first two components explaining 96.1% of the total variance. The findings revealed varied concentrations of heavy metals across all water sources. Statistical analyses underscored the complex relationship between water sources and heavy metal contamination levels, highlighting the need for targeted interventions to improve water quality and mitigate health risks. The study highlights the urgent need for monitoring and mitigation efforts to ensure safe drinking water and mitigate health risks associated with heavy metal contamination.

Cadmium exposure and its association with oxidative stress, MT1A methylation, and idiopathic male infertility in Egypt: A case-control study

Idiopathic male infertility, a significant health concern, lacks a clear etiology. Cadmium (Cd), a widespread environmental pollutant known to impact male reproductive health negatively, can accumulate in mussels, a common food source in Egypt. This study investigated the link between ecological Cd exposure, oxidative stress, MT1A methylation, and idiopathic male infertility in two regions of Alexandria. Thirty-three infertile men and 33 fertile controls were included. Cd levels were measured in mussels from the study sites and in participants' blood and semen. Biomarkers reflecting Cd exposure and its effects were assessed. Mussel Cd levels exceeded regulatory limits. Infertile men revealed significantly higher blood and semen Cd levels, reduced semen quality, increased oxidative stress, and elevated MT1A methylation compared to controls. MT1A methylation was inversely correlated with sperm count and is the strongest predictor of idiopathic male infertility, demonstrating the lowest p-value and considerable effect size. This study suggests that environmental Cd exposure, potentially through mussel consumption, may contribute to idiopathic male infertility in Egypt by increasing oxidative stress, inducing epigenetic modifications, and impairing semen quality. These findings underscore the need for further research into the mechanisms underlying Cd-induced male infertility and the development of preventative strategies.

Pretreatment with aqueous Moringa oleifera Lam. leaf extract prevents cadmium-induced hepatotoxicity by improving cellular antioxidant machinery and reducing cadmium accumulation

Cadmium (Cd) is a highly harmful pollutant that poses a serious threat to human health. The liver is the primary organ for Cd accumulation, and Cd-induced hepatotoxicity has been shown to be strongly correlated with an oxidative imbalance in hepatocytes. Our previous studies in the eukaryotic model organism Saccharomyces cerevisiae revealed that not only co-treatment but also pretreatment with aqueous Moringa oleifera Lam. leaf extract (AMOLE) effectively mitigated Cd toxicity by reducing intracellular Cd accumulation and Cd-mediated oxidative stress. In this study, we therefore investigated the preventive effect of AMOLE against Cd toxicity in human HepG2 hepatocytes. The results showed that, similar to the case of the yeast model, pretreatment with AMOLE prior to Cd exposure also significantly inhibited Cd-induced oxidative stress in HepG2 cells. Untargeted LC-MS/MS-based metabolomic analysis of AMOLE revealed that its major phytochemical constituents were organic acids, particularly phenolic acids and carboxylic acids. Additionally, DPPH-HPTLC fingerprints suggested that quercetin and other flavonoids possibly contribute to the antioxidant activities of AMOLE. Based on our findings, it appears that pretreatment with AMOLE prevented Cd-induced hepatotoxicity via three possible mechanisms: i) direct elimination of free radicals by AMOLE antioxidant compounds; ii) upregulation of antioxidant defensive machinery (GPx1, and HO-1) via Nrf2 signaling cascade to improve cellular antioxidant capacity; and iii) reduction of intracellular Cd accumulation, probably by suppressing Cd uptake. These data strongly suggest the high potential of AMOLE for clinical utility in the prevention of Cd toxicity.

A Comparative Study to Explore the Variability of Heavy Metal Concentration in the Teeth of Residents of Non-gated Versus Gated Societies

Human populations face increasing exposure to heavy metals, which pose significant health risks. Dental tissues, such as dentin and enamel, provide a reliable biomarker for assessing long-term heavy metal exposure due to their stable nature. This study aims to explore the variability of heavy metal concentrations in the teeth dentine of residents living in gated versus non-gated societies near the Yamuna River around the Jamia Millia Islamia, New Delhi, India. Sixty-nine participants were enrolled, 27 from gated societies and 42 from non-gated societies. Participants underwent elective dental extraction, following which heavy metal concentrations were measured in extracted tooth dentine using atomic absorption spectrophotometry. Demographic data including age, gender, tooth types, and drinking water sources were recorded. Statistical analysis included Mann-Whitney's test, Spearman correlation heatmap, and principal component analysis (PCA). Residents of non-gated societies exhibited significantly (p < 0.005) higher mean concentrations of heavy metals compared to gated societies except for cadmium (p = 0.495). Subgroup analysis based on drinking water sources revealed significant (p < 0.001) variations in heavy metal concentrations, suggesting the influence of water quality on environmental exposure. PCA provided insights into underlying trends and correlations among heavy metal variables. This study provides valuable insights into heavy metal contamination among residents living near the Yamuna River, highlighting disparities in exposure based on residential environment and drinking water sources. Participants from non-gated societies exhibited higher mean concentrations of heavy metals compared to those from gated societies, emphasizing the influence of socio-economic factors, urban infrastructure and environmental management practices on heavy metal accumulation. The study's findings underscore the need for targeted interventions to address heavy metal exposure across diverse population groups, improve water quality standards, and enhance access to safe drinking water.

Phytoavailability, translocation, and accompanying isotopic fractionation of cadmium in soil and rice plants in paddy fields

Rice consumption is a major pathway for human cadmium (Cd) exposure. Understanding Cd behavior in the soil-rice system, especially under field conditions, is pivotal for controlling Cd accumulation. This study analyzed Cd concentrations and isotope compositions (δ114/110Cd) in rice plants and surface soil sampled at different times, along with urinary Cd of residents from typical Cd-contaminated paddy fields in Youxian, Hunan, China. Soil water-soluble Cd concentrations varied across sampling times, with δ114/110Cdwater lighter under drained than flooded conditions, suggesting supplementation of water-soluble Cd by isotopically lighter Cd pools, increasing Cd phytoavailability. Both water-soluble Cd and atmospheric deposition contributed to rice Cd accumulation. Water-soluble Cd's contribution increased from 28-52% under flooded to 58-87% under drained conditions due to increased soil Cd phytoavailability. Atmospheric deposition's contribution (12-72%) increased with potential atmospheric deposition flux among sampling areas. The enrichment of heavy Cd isotopes occurred from root-stem-grain to prevent rice Cd accumulation. The different extent of enrichment of heavy isotopes in urine indicated different Cd exposure sources. These findings provide valuable insights into the speciation and phytoavailability changes of Cd in the soil-rice system and highlight the potential application of Cd isotopic fingerprinting in understanding the environmental fate of Cd.

Permanent and decidua dentition as chronological biomarkers of heavy metal contamination: A review of the forensic literature

STATEMENT OF PROBLEM

Contamination with heavy metals (HM) has great environmental consequences in the environment due to lack of biodegradation, in addition, accumulation in living beings causes defects in tissues and organs, deteriorating their function and inducing a wide spectrum of diseases. Human biomonitoring consists of the periodic measurement of a certain chemical substance or metabolite in a particular population, using matrices that can be acute or chronic. Teeth are chronic matrices that have great characteristics of resistance and chronological storage of information. This review aims to identify the mechanisms, spatial location, and affinity of HM within teeth, along with understanding its applicability as a chronological record matrix in the face of HM contamination.

MATERIAL AND METHODS

A systematic search review was performed using the PubMed/Medline, Web of Science, and Scopus metasearch engines, and the terms "teeth" OR "dental" OR "tooth" AND "heavy metals" were intersected. Complete articles are included in Spanish, English and Portuguese without time restrictions, involving studies in humans or in vitro; Letters to the editor, editorials and those that did not refer to information on the incorporation and relationship of HM with the teeth were excluded.

RESULTS

837 published articles were detected, 91 were adjusted to the search objective, and 6 were manually included. Teeth are structures with a great capacity for information retention in the face of HM contamination due to low physiological turnover and their long processes of marked formations by developmental biorhythm milestones such as the neonatal line (temporal reference indicator). The contamination mechanisms inside the tooth are linked to the affinity of hydroxyapatite for HM; this incorporation can be in the soft matrix during the apposition phase or as part of the chemical exchanges between hydroxyapatite and the elements of the environment.

CONCLUSION

The teeth present unique characteristics of great resistance and affinity for HM, as well as a chronological biomarker for human biomonitoring, so they can be used as means of expertise or evidence to confirm or rule out a fact of environmental characteristics in the legal field.

The effects of cadmium on selected oxidative stress parameters and the content of photosynthetic pigments in cucumber Cucumis sativus L

BACKGROUND

Environmental pollution by cadmium (Cd) is currently a common problem in many countries, especially in highly industrialised areas. Cd present in the soil can be absorbed by plants through the root system.

AIM

The aim of the present study was to investigate the effects of cadmium on the metabolic activity of cucumber plants (Cucumis sativus L.) and the accumulation and distribution of Cd in the organs of the plants.

METHODS

Cucumber seeds (3 g) were exposed to 0.76, 1.58 or 4.17 mg Cd/L (applied as CdCl2 solutions). The activity of selected antioxidant enzymes - glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT), lipid peroxidation and the content of photosynthetic pigments were determined in 6-week-old cucumber plants. In addition, intake of Cd has been determined by flame atomic absorption spectrometry (F-AAS).

RESULTS

The results show that the applied cadmium concentrations affected the activity of antioxidant enzymes. An increase in CAT activity and a decrease in SOD activity were observed in all cucumber organs analysed. GSH-Px activity increased in the roots and stems. Surprisingly, GSH-Px activity decreased in the leaves. The level of lipid peroxidation was usually unchanged (the only one statistically significant change was a decrease in the concentration of malondialdehyde in the leaves which was observed after exposure to the highest Cd concentration). The applied Cd concentrations had no effect on the content of photosynthetic pigments. The highest cadmium content was found in the roots of cucumber plants. Cd tends to accumulate in the roots and a small amount was translocated to the stems and leaves, which was confirmed with the translocation factor (TF).

CONCLUSIONS

The results indicate that the range of cadmium concentrations used, corresponding to the level of environmental pollution recorded in Europe, effectively activates the antioxidant enzyme system, without intensifying lipid peroxidation or reducing the content of photosynthetic pigments.

Revealing the Sources of Cadmium in Rice Plants under Pot and Field Conditions from Its Isotopic Fractionation

The highly excessive uptake of cadmium (Cd) by rice plants is well known, but the transfer pathway and mechanism of Cd in the paddy system remain poorly understood. Herein, pot experiments and field investigation were systematically carried out for the first time to assess the phytoavailability of Cd and fingerprint its transfer pathway in the paddy system under different treatments (slaked lime and biochar amendments), with the aid of a pioneering Cd isotopic technique. Results unveiled that no obvious differences were displayed in the δ114/110Cd of Ca(NO3)2-extractable and acid-soluble fractions among different treatments in pot experiments, while the δ114/110Cd of the water-soluble fraction varied considerably from -0.88 to -0.27%, similar to those observed in whole rice plant [Δ114/110Cdplant-water ≈ 0 (-0.06 to -0.03%)]. It indicates that the water-soluble fraction is likely the main source of phytoavailable Cd, which further contributes to its bioaccumulation in paddy systems. However, Δ114/110Cdplant-water found in field conditions (-0.39 ± 0.05%) was quite different from those observed in pot experiments, mostly owing to additional contribution derived from atmospheric deposition. All these findings demonstrate that the precise Cd isotopic compositions can provide robust and reliable evidence to reveal different transfer pathways of Cd and its phytoavailability in paddy systems.

Investigation of elemental composition in red teff grains using inductively coupled plasma optical emission spectroscopy (ICP OES), Sire District, Arsi zone, Ethiopia

BACKGROUND

Minerals are important not only for better plant growth and development but also for human and animal nutrition. It is known that east and west Gojam in the Amhara region and east and west Shoa areas in the Oromia region Ethiopia's most teff growing areas. However, there is no information on the mineral content and nutritional worth of Teff Sire district, Arsi zone, Ethiopia. Since ICP OES is a powerful technique to examine elemental compositions even in lower concentration, it is used in this work to investigate the elemental composition of red teff samples.

METHODS

The elemental compositions of red Teff grain samples were determined using ICP-OES from three sites: S1, S2, and S3 of Sire district, Arsi zone, Ethiopia. Wet digestion of the teff samples was carried out by weighing 0.5 g red teff sample and digested with 8 ml HNO3 and 2 ml H2O2 (30%) for 3:00 h at a temperature of 100℃ on hot plate. The investigations of method validation, limit of detection and limit of quantification were also carried out.

RESULTS

The average amount of elements in red teff sample obtained as 172-280 mg/kg Fe, 13-76 mg/kg Mn, 8.2-8.5 mg/kg Cu, 24-26 mg/kg Zn, and toxic trace elements 0.12-0.29 mg/kg Pb and 0.15-0.22 mg/kg Cd. The limit of detection found in ranges from 0.21 mg Kg-1 to 10.44 mg Kg-1 whereas quantification limit resulted in 0.7 mg Kg-1 to 34.8 mg Kg-1 for the metals under consideration. The method was validated by its linear range in the concentration range of 0.028-1.4 ppm or 0.056-2.8 ppm and excellent recovery result was achieved in the range of 90-120%.

CONCLUSION

This study aimed to investigate the mineral content in red teff cultivated in Ethiopia specifically Arsi zone by using ICP OES. From the obtained results, Iron was the first abundant essential element in red teff compared to Mn, Cu and Zn. The level of trace elements: Cd and Pb in the samples slightly above the acceptable limit, possibly due to agricultural practices like usage of fertilizers, pesticides, and other industrial products. Overall, this red teff elemental composition information contributes to the nutrition database and food safety in Ethiopia and beyond.

Experimental study for inorganic and organic profiling of toy makeup products: Estimating the potential threat to child health

Inorganic elements are added to toys as impurities to give desired stability, brightness, flexibility, and color; however, these elements may cause numerous health issues after acute or chronic exposure. In this study, the inorganic profile of 14 elements (Al, As, Ba, Cd, Co, Cr, Cu, Hg, Mn, Ni, Se, Sb, Pb, and Zn) in 63 toy makeup products was identified by inductively coupled plasma-mass spectrometry after microwave acid digestion method. Additionally, organic allergen fragrance was investigated by gas chromatography-mass spectrometry. The systemic exposure dosage (SED), margin of safety (MoS), lifetime cancer risk (LCR), hazard quotient (HQ), and hazard indices were used to assess the safety evaluation. Then, 57 out of 63 samples (90.48%) exceeded the limits at least for one toxic element with descending order Ni > Cr > Co > Pb > Sb > Cd > As > Hg. The SED values were compared with tolerable daily intake values and remarkably differences were found for Al and Pb. The MoS values for 57.15% of samples exceeded the limit value for Al, As, Cd, Co, Hg, Mn, Sb, and Zn elements. The LCR values were observed at 100% (n = 63), 79.37% (n = 50), 85.71% (n = 54), 77.78% (n = 49), and 18.87% (n = 10) for Cr, Ni, As, Pb, and Cd, respectively. Also, the skin sensitization risks were obtained for Cr and Ni at 26.980% (n = 17) and 9.52% (n = 6), respectively. The HQ values for 80% of samples were found to be ≥ 1 at least for one parameter. The investigation of fragrance allergens in samples did not show any significant ingredients. As a result, toy makeup products marketed in local stores were found to be predominantly unsafe. Children should be protected from harmful chemicals by regular monitoring and strict measures.

Influence of soil amendments on phytostabilization, localization and distribution of zinc and cadmium by marigold varieties

Marigolds (Tagetes erecta L.) were evaluated for phytoremediation potential of cadmium (Cd) and zinc (Zn) as a function of amendment application to soil. Vermicompost (V), biodigestate (Bi), and combined V + Bi (VBi) were used as soil amendments in Zn and Cd co-contaminated soils. Application of soil amendments can alter physicochemical properties of soils, particularly pH, EC, CEC and nutrient concentrations. The VBi treatment resulted in highest percentage growth rate in biomass (52 %) for the Twenty yellow variety of marigold. Also, in the VBi treatment, leaves of Dragon yellow variety exhibited maximal accumulation of Zn and Cd. Flower extracts of Twenty yellow in the V treatment had substantial carotenoid content (71.7 mg L-1) and lowest IC50 value (43.7 mg L-1), thus indicating it had highest DPPH free radical scavenging activity. Dragon yellow exhibited highest values of ferric reducing antioxidant power (FRAP; 2066 mg L-1), total flavonoids content (TFC; 64.1 mg L-1), and total phenolics content (TPC; 50.9 mg L-1). Using X-ray fluorescence (XRF) spectroscopy, the atomic percentages of Zn and Cd in all marigold varieties and treatments showed similar patterns over flower surfaces, seeds, and flower petals in descending order. Prime yellow in the V treatment resulted in higher Zn accumulation in roots (bioconcentration factor of root value) > 1 and translocation factor value < 1, indicating an enhanced ability of the plant for phytostabilization. Application of V altered antioxidant activities and production of bioactive compounds as well as enhanced the excluder potential of Cd and Zn, particularly in the Prime yellow variety. Application of Bi contributed to increased flower numbers, suggesting that floriculturists cultivating marigolds for ornamental purposes may be able to generate revenue in terms of productivity and quality of flowers when marigolds are grown on contaminated land.

Pollutants to pathogens: The role of heavy metals in modulating TGF-β signaling and lung cancer risk

Lung cancer is a malignant tumor that develops in the lungs due to the uncontrolled growth of aberrant cells. Heavy metals, such as arsenic, cadmium, mercury, and lead, are metallic elements characterized by their high atomic weights and densities. Anthropogenic activities, such as industrial operations and pollution, have the potential to discharge heavy metals into the environment, hence presenting hazards to ecosystems and human well-being. The TGF-β signalling pathways have a crucial function in controlling several cellular processes, with the ability to both prevent and promote tumor growth. TGF-β regulates cellular responses by interacting in both canonical and non-canonical signalling pathways. Research employing both in vitro and in vivo models has shown that heavy metals may trigger TGF-β signalling via complex molecular pathways. Experiments conducted in a controlled laboratory environment show that heavy metals like cadmium and arsenic may directly bind to TGF-β receptors, leading to alterations in their structure that enable the receptor to be phosphorylated. Activation of this route sets in motion subsequent signalling cascades, most notably the canonical Smad pathway. The development of lung cancer has been linked to heavy metals, which are ubiquitous environmental pollutants. To grasp the underlying processes, it is necessary to comprehend their molecular effect on TGF-β pathways. With a particular emphasis on its consequences for lung cancer, this abstract delves into the complex connection between exposure to heavy metals and the stimulation of TGF-β signalling.

Pollutant bioaccumulation in sentinel fish chronically exposed in Iguaçu river reservoirs (Southern Brazil) and human health risk of fish consumption

Bioaccumulation studies in fish mark the initial phase of assessing the risk of chemical exposure to biota and human populations. The Iguaçu River boasting a diverse endemic ichthyofauna, is grappling with the repercussions of human activities. This study delved into the bioaccumulation of micropollutants, the early-warning effects on Rhamdia quelen and Oreochomis niloticus in the Segredo Reservoir (HRS) and the potential risk of human exposure. Two groups of caged fish in three sites of the reservoir were exposed during the autumn-winter and spring-summer, while a third group (O. niloticus) underwent a twelve-month exposure, and inorganic and organic chemicals analysis in water, sediment, and biota. Additionally, metallothionein expression and genotoxicity were employed as biomarkers. PAHs, PCBs, Al, Cu, Fe, and As in water and DDTs, Cu, Zn, and As in sediment surpassed the thresholds set by Brazilian regulations, where DDT exhibited bioaccumulation in muscle, alongside metals in liver, kidney, gills, and muscle tissues. R. quelen showed metallothionein expression whereas DNA damage and NMA frequencies were elevated in target organs and in brain and erythrocytes of O. niloticus during summer. In this species the DNA damage in liver was remarkable after twelve months. Target Hazard Quotients and Cancer Risk values shedding light on the vulnerability of both children and adults. The reservoir's conditions led to heightened sensitivity to micropollutants for R. quelen species. The data presented herein provides decision-makers with pertinent insights to facilitate effective management and conservation initiatives within the Iguaçu Basin.

Evidence for the accumulation of toxic metal(loid)s in agricultural soils impacted from long-term application of phosphate fertilizer

Phosphate fertilizers may contain elevated concentrations of toxic metals and metalloids and therefore, their excessive application can result in the accumulation of both phosphorus (P) and metal(loid)s in agricultural soils. This study aims to investigate the occurrence, distribution, and potential plant-availability of metal(loid)s originating from phosphate fertilizer in a long-term experimental field at the Tidewater Research Station in North Carolina, where topsoil (10-20 cm deep) and subsoil (up to 150 cm deep) samples were collected from five plots with consistent and individually different application rates of P-fertilizer since 1966. We conducted systematic analyses of P and metal(loid)s in bulk soils, in the plant available fraction, and in four sequentially extracted soil fractions (exchangeable, reducible, oxidizable, and residual). The results show that P content in topsoils were directly associated with the rate of P-fertilizer application (ρ = 1, p < 0.05). Furthermore, P concentrations were highly correlated with concentrations of Cd, U, Cr, V, and As in the bulk topsoil (ρ > 0.58, p < 0.05), as well as the potential plant-available fraction (ρ > 0.67, p < 0.01), indicating the accumulation of the fertilizer-derived toxic metal(loid)s in the topsoil. Significant correlations (p < 0.001) of metal(loid)s concentrations between the bulk soil and the potential plant-available fraction raises the possibility that P-fertilizer application could increase the accumulation of toxic metal(loid)s in plants, which could increase human exposure. Results from sequential leaching experiments revealed that large portions of the trace elements, in particular Cd, occur in the soluble (exchangeable and reducing) fractions of topsoil with higher P-fertilizer input, whereas the levels of redox-sensitive elements (As, V, U, Cr) were higher in the reducible and oxidizable fractions of the soils. Overall, the data presented in this study demonstrate the effect of long-term P-fertilizer application on the occurrence and accumulation of a wide range of toxic metal(loid)s in agricultural topsoil.

Enhancing cadmium phytoremediation of Chlorophytum comosum (Thunb.) Jacques by applying cadmium-resistant bacterial tablet

This study aims to formulate bacterial tablets of cadmium (Cd)-resistant Micrococcus sp. MU1, an indole-3-acetic acid-producer, for soil inoculation to improve Cd phytoremediation by Chlorophytum comosum (Thunb.) Jacques. The viability of Micrococcus sp. MU1 in tablets after storage at room temperature and 4 °C was determined. The ability of Micrococcus sp. tablets and cell suspensions on stimulating growth and Cd accumulation in C. comosum was compared. The results found that the viability of Micrococcus sp. tablets stored at room temperature and 4 °C for 2 months were 29.2 and 97.9%, respectively. After 2 months of growth in pots, the dry biomass weights of C. comosum amended with Micrococcus sp. tablet and cell suspension were greater than that of uninoculated control by 1.4- and 1.3-fold, respectively. Cd concentrations in the roots and shoots of C. comosum inoculated with bacterial tablet and bacterial suspension were not significantly different (p < 0.05) and were greater than that of the uninoculated plants. In addition, plants inoculated with Micrococcus sp. tablet and cell suspension exhibited superior phytoextraction performance, bioaccumulation factor, and translocation factor, indicating equal performance of both bacterial forms on boosting Cd phytoremediation efficiency in C. comosum. These findings suggest that soil inoculation with Micrococcus sp. tablet as a ready-to-use inoculum is a novel approach to promote phytoremediation of C. comosum in Cd-contaminated agricultural soil.

Involvement of the heat shock response (HSR) regulatory pathway in cadmium-elicited cerebral damage

The heat shock response (HSR) is a cellular protective mechanism that is characterized by the induction of heat shock transcription factors (HSFs) and heat shock proteins (HSPs) in response to diverse cellular and environmental stressors, including cadmium (Cd). However, little is known about the relationship between the damaging effects of Cd and the HSR pathway in the chicken cerebrum following Cd exposure. To explore whether Cd exposure elicits cerebral damage and triggers the HSR pathway, chicks were exposed to Cd in the daily diet at different concentrations (35, 70, or 140 mg/kg feed) for 90 days, while a control group was fed the standard diet without Cd. Histopathological examination of cerebral tissue from Cd-exposed chickens showed neuronal damage, as evidenced by swelling and degeneration of neurons, loss of neurons, and capillary damage. Cd exposure significantly increased mRNA expression of HSF1, HSF2, and HSF3, and mRNA and protein expression of three major stress-inducible HSPs (HSP60, HSP70, and HSP90). Moreover, Cd exposure differentially modulated mRNA expression of small HSP (sHSPs), most notably reducing expression of HSP27 (HSPB1). Furthermore, Cd exposure increased TUNEL-positive neuronal apoptotic cells and up-regulated protein expression of caspase-1, caspase-8, caspase-3, and p53, leading to apoptosis. Taken together, these data demonstrate that activation of the HSR and apoptotic pathways by Cd exposure is involved in Cd-elicited cerebral damage in the chicken. Synopsis for the graphical abstract Cadmium (Cd)-induced neuronal damage triggers the heat shock response (HSR) by activating heat shock transcription factors (HSFs) and subsequent induction of major heat shock proteins (notably, HSP60, HSP70, and HSP90). Moreover, Cd exposure activates caspase-1, caspase-8, caspase-3, and p53 protein, thereby resulting in neuronal apoptosis in the chicken brain.

Mapping the metabolic characteristics of probiotic-fermented Ganoderma lucidum and its protective mechanism against Cd-induced nephrotoxicity

An animal model of Cd-induced kidney damage was designed to investigate the nephroprotective potential of the probiotic-fermented Ganoderma lucidum (FGL) via metabonomic analysis. The results showed that FGL enhanced sugar and amino acid metabolism. The interaction of Ganoderma lucidum (GL) and probiotics efficiently elevated short-chain fatty acid production following gut microbiota fermentation. The current data revealed that the FGL intervention alleviated Cd-induced nephrotoxicity via elevating the activity of antioxidant enzymes and decreasing the levels of pro-inflammatory and apoptotic factors. Based on transcriptome analysis, FGL intervention mediated renal dysfunction via decreasing the expressions of Nos2, Tnfsf14, S100a9, Map3k6 and Hk3, which were involved in oxidative stress, inflammatory response and the apoptosis process. The current study highlights a new approach for achieving positive nephroprotection via natural product intervention.

Gallic Acid Ameliorates Cadmium Effect on Osteogenesis by Activation of Alkaline Phosphatase and Collagen Synthesis

OBJECTIVE

We previously reported that cadmium (Cd) inhibits osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). In addition, gallic acid (GA) improves BMSC differentiation. Here, we aim to study the ability of GA to prevent osteogenic inhibition induced by Cd.

MATERIALS AND METHODS

In this experimental study, BMSCs were extracted and purified from Wistar rats and their viability was determined in the presence of Cd and GA. The results indicated that 1.5 μM Cd and 0.25 μM of GA were appropriate for further investigation. After 20 days in osteogenic medium, matrix production was analysed by alizarin red, calcium content, and alkaline phosphatase (ALP) activity. Osteogenic-related genes and collagen 1A1 (COL1A1) protein expressions were investigated. The preventive effect of GA on oxidative stress and metabolic change induced by Cd was estimated.

RESULTS

GA counteracted the inhibitory effect of Cd on matrix production and significantly (P=0.0001) improved the osteogenic differentiation ability of BMSCs. Also, GA prevented the toxic effect of Cd on osteogenic-related gene expressions and nullified the reducing effect of Cd on COL1Al and ALP activity. A significant reduction (P=0.0001) in malondialdehyde and lactic acid concentration showed that GA counteracted both oxidative stress and metabolic changes caused by Cd.

CONCLUSION

GA prevented the toxic effect of Cd, an environmental pollutant and a factor in osteoporosis.

Mitigation strategies for excessive cadmium in rice

Cadmium (Cd)-contaminated rice is a human food safety problem that lacks a clear solution. A large amount of rice having an excessive Cd content is processed yearly, but it cannot be discarded and placed in landfills because it will cause secondary pollution. How do we best cope with this toxic rice? From the perspectives of food safety, food waste prevention, and human hunger eradication, the use of contemporary physical, chemical, and biological techniques to lower the Cd content in postharvest Cd-contaminated rice so that it can be used safely is the best course of action. In this review, the contamination, chemical speciation, and distribution of Cd in rice are analyzed and discussed, as are the methods of Cd removal from rice, including a comparison of the advantages and disadvantages of various techniques. Owing to the limitations of current technology, research and technological development recommendations for removing Cd from rice grain are presented. The chemical and biological methods produce higher Cd-removal rates than physical methods. However, they are limited to small-scale laboratory applications and cannot be applied on a large industrial scale. For the efficient safe removal of Cd from food, mixed fermentation with lactic acid bacteria and yeast has good application prospects. However, limited strains having high Cd-removal rates have been screened. In addition, modern biotechnology has rarely been applied to reduce rice Cd levels. Therefore, applying genetic engineering techniques to rapidly obtain microorganisms with high Cd-removal rates in rice should be the focus of future research.

Pollution of the Niger Delta with total petroleum hydrocarbons, heavy metals and nutrients in relation to seasonal dynamics

The African Niger Delta is among the world's most important wetlands in which the ecological effects of intensive oil exploitation and global change are not well documented. We characterized the seasonal dynamics and pollution with total-petroleum-hydrocarbons (TPHs), heavy-metals (HMs) and nutrient-loads in relation to climate-driven variables. High TPH concentrations up to 889 mg/L and HMs up to 13.119 mg/L were found in water samples, with pronounced spatio-temporal variation throughout the year. HM pollution index and contamination factor indicate serious ecological and human health hazards, especially for Cd, Cu, Hg, and Ni. Significant differences in TPHs/HMs were observed between sites and seasons, with correlations between TPHs-HMs, and climate-variables and TPHs-HMs. Nutrient levels, turbidity, salinity, temperature, and SO42- were high and interlinked with the variability of TPHs/HMs being greatest during wet season. These findings suggest an urgent need for improved pollution control in the Niger Delta taking into account the observed spatio-temporal variation and the exacerbation of effects in light of climate change. Given the high levels of contamination, further assessments of exposure effects and bioaccumulation in biota should include future climate change scenarios and effects on humans who intensively depend on the system for drinking water, food supply and livelihood.

Vitamin D Alleviates Cadmium-Induced Inhibition of Chicken Bone Marrow Stromal Cells' Osteogenic Differentiation In Vitro

Vitamin D is a lipid soluble vitamin that is mostly used to treat bone metabolism-related diseases. In this study, the effect of Cd toxicity in vitro on osteogenic differentiation derived from BMSCs and the alleviating effect of lα, 25-(OH)2D3 were investigated. Cell index in real time was monitored using a Real-time cell analyzer (RTCA) system. The activity of alkaline phosphatase (ALP), and the calcified nodules and the distribution of Runx2 protein were detected using ALP staining, alizarin red staining, and immunofluorescence, respectively. Furthermore, the mitochondrial membrane potential and the apoptotic rate of BMSCs, the mRNA levels of RUNX2 and type Ⅰ collagen alpha2 (COL1A2) genes, and the protein expression of Col1 and Runx2 were detected using flow cytometry, qRT-PCR and western blot, respectively. The proliferation of BMSCs and osteogenic differentiation were enhanced after treatment with different concentrations of lα, 25-(OH)2D3 compared with the control group. However, 5 μmol/L Cd inhibited the proliferation of BMSCs. In addition, 10 nmol/L lα,25-(OH)2D3 attenuated the toxicity and the apoptosis of BMSCs treated by Cd, and also promoted the osteogenic differentiation including the activity of ALP, and the protein expression of Col1 and Runx2. lα, 25-(OH)2D3 can alleviate cadmium-induced osteogenic toxicity in White Leghorn chickens in vitro.

Heavy metals in vegetables: a review of status, human health concerns, and management options

For sustainable global growth, food security is a prime concern issue, both quantitatively and qualitatively. Adverse effects on crop quality from contaminants like heavy metals have affected food security and human health. Vegetables comprise the essential and nutritious part of the human diet as they contain a lot of health-promoting minerals and vitamins. However, the inadvertent excess accumulation of heavy metals (As, Cd, Hg, and Pb) in vegetables and their subsequent intake by humans may affect their physiology and metabolomics and has been associated with diseases like cancer, mental retardation, and immunosuppression. Many known sources of hazardous metals are volcano eruptions, soil erosion, use of chemical fertilizers in agriculture, the use of pesticides and herbicides, and irrigation with wastewater, industrial effluents, etc. that contaminate the vegetables through the soil, air and water. In this review, the problem of heavy metal contamination in vegetables is discussed along with the prospective management strategies like soil amendments, application of bioadsorbents, membrane filtration, bioremediation, and nanoremediation.

Cadmium dietary exposure assessment in the adult population and pre-school children in the Republic of Serbia

Cadmium (Cd) is a toxic metal, present in all matrices of the environment and a common food contaminant. Human exposure to it may elicit many diverse health impairments. The aim of this study was to assess the dietary exposure to Cd for the adult population and preschool children in Serbia using probabilistic methodology. We measured Cd in 11,227 food samples belonging to 50 food items on the Serbian market. Cd was detected in 90% of the tested food items, and in 30.8% of the overall tested samples. The food item that contributed the most to total dietary Cd intake was potatoes (median Cd concentration of 7 ng/g) in adults, and fruit and vegetable juices in children (median Cd concentration of 19 ng/g). Weekly Cd intake shown as 50th and 95th percentiles were 2.54 and 4.74 µg/kg bw in the adult population, and 3.29 and 4.93 µg/kg bw in children. The results of this study are rather preliminary and should be considered as an indication of the need for further, more refined research, which would contribute to a more realistic risk assessment as a high-priority approach, especially in the case of vulnerable subpopulations such as children. Abbreviations: AT SDR: Agency for Toxic Substances and Disease Registry; EEA: European Environment Agency; EFSA: European Food Safety Authority; FAO/WHO: Food and Agriculture Organization/World Health Organization; HI: hazard index; IARC: International Agency for Research on Cancer; JECFA: Joint FAO/WHO Expert Committee on Food Additives; LOD: limit of detection; Cd: cadmium; TWI: tolerable weekly intake; UNEP: United Nations Environment Program; WI: weekly intake.

Clue of zinc oxide and copper oxide nanoparticles in the remediation of cadmium toxicity in Phaseolus vulgaris L. via the modulation of antioxidant and redox systems

The present study represents new evidence of the successful use of metal oxide nanoparticles in the remediation of heavy metals. Zinc oxide nanoparticles (ZnO NP) and copper oxide nanoparticles (CuO NP) were assessed to alleviate cadmium (Cd) toxicity in Phaseolus vulgaris L. seedlings and plants. Monitoring physiological and metabolic parameters allowed to elucidate Cd mechanism and process whereby it exerts phytotoxic effects on bean. The response of P. vulgaris seedlings is NP dose-dependent (10 mg/L, 50 mg/L, 100 mg/L, and 200 mg/L). Similarly, applied concentrations triggered a differential response of growing plants in terms of length and biomass. Our physiological data allowed to select 100 mg/L as the most appropriate concentration to apply, in order to avoid any risk of phytotoxicity. The regulatory mechanisms by which ZnO NP and CuO NP act are for the first time compared in the embryonic axes of bean seedlings under Cd stress. Both NP were able to reduce the hypergeneration of hydrogen peroxide (H₂O₂). They also acted via enhancing ROS scavenging enzymatic capacity, and activity of antioxidant enzymes CAT, APX, GPOX, GPX, and GR, and inhibited the activity of ROS producing enzymes such as GOX and NOX. Another mechanistic effect of NP consisted of the modulation of redox enzymes Trx, NTR, Fd, and FNR evolved in cellular homeostasis and maintaining reduced status in cells. Taken together, ZnO NP triggered more significant metabolic regulations allowing to mitigate the oxidative damage caused by Cd.

Milk vetch returning reduces rice grain Cd concentration in paddy fields: Roles of iron plaque and soil reducing-bacteria

Milk vetch (MV, Astragalus sinicus L.) is used in agricultural production as a green manure; however, its impact on accumulation levels of heavy metals (e.g., Cd) in rice remains poorly understood. This study investigated the effects of MV on Cd accumulation in rice, iron plaque formation, soil properties, and the soil microbial community structure through field experiments. The results showed that MV reduced Cd concentration in the roots, stem, leaves, and grains by 33%, 60%, 71%, and 49%, respectively. Chemical fertilizer and MV treatment promoted iron plaque formation, and MV considerably increased the Fe/Mn ratio in the iron plaque. More importantly, MV inhibited Cd transportation from the root iron plaque to the root by 74%. The concentrations of CaCl₂-extractable Cd, available phosphorus, and available potassium, as well as the cation exchange capacity and urease activity, were significantly reduced in the MV treatment. Furthermore, 16 S rDNA high-throughput sequencing results of the soil microbial community structure showed that compared with the control, MV increased the soil microbial richness, increased the relative abundance of anaerobic microorganisms, and significantly increased the relative abundance of Thermodesulfovibrio and Geobacter at the genus level. The increase in anaerobic microbial abundance was closely related to the decrease in CaCl₂-extractable Cd concentration. The application of MV promoted the formation of iron plaque, inhibited the transport of Cd, increased the abundance of anaerobic microorganisms, decreased the CaCl₂-extractable Cd concentration, and reduced the Cd concentration in rice grain.

Arbuscular mycorrhizal fungi affecting the growth, nutrient uptake and phytoremediation potential of different plants in a cadmium-polluted soil

Heavy metals stress is of great concern as it contaminates the environment affecting human health and the growth and quality of different plants including the medicinal ones. The use of soil microbes is among the most efficient methods for treating heavy-metal polluted soils. The objective was to investigate the effects of arbuscular mycorrhizal (AM) fungi (Glomus mosseae) on the nutrient uptake (N, P, K, Fe, and Mn,) and Cd removal of different plants including rosemary (Salvia rosmarinus), amaranth (Amaranthus sp.), and ornamental cabbage (Brassica oleracea) in a Cd-polluted soil. The experiment was a three-way factorial on the basis of a randomized complete block design with three replicates. The experimental soil was sprayed with Cd (0, 10, 25, 50, 75 and 100 mg kg^-1), and after 2 months it was inoculated with 100 g of mycorrhizal inoculums, and was planted in 4-kg pots. Plant growth (root and aerial part) and nutrient uptake as well as Cd removal from the contaminated soil were significantly affected by the experimental treatments. AM fungi significantly increased plant P uptake (35%) compared with N (24%), K (4%), Fe (24%) and Mn (13%). According to the results, rosemary was the most effective plant for the bioremediation of the soil. There were significant differences between plant roots and aerial part in terms of plant nutrient uptake and phytoremediation potential. Although increasing Cd concentration decreased plant growth and nutrient uptake, mycorrhizal fungi was able to alleviate the stress by significantly increasing plant growth, nutrient uptake and phytoremediation potential.

Cadmium-resistant Streptomyces stimulates phytoextraction potential of Crotalaria juncea L. in cadmium-polluted soil

This work evaluated the competence of two strains of cadmium (Cd)-resistant Streptomyces, namely Streptomyces rapamycinicus K5PN1, an indole-3-acetic acid (IAA) producer, and Streptomyces cyaneus 11-10SHTh, a siderophore producer on promoting Cd phytoextraction by sunn hemp. The results showed that S. rapamycinicus improved root elongation of sunn hemp seedlings under Cd stress conditions. S. rapamycinicus and S. cyaneus were colonized on the root surface of sunn hemp at concentrations of 2.3 × 10⁴ and 6.4 × 10³ CFU g^-1 root fresh weight, respectively. The results of pot-culture experiments showed that S. rapamycinicus increased the root and shoot lengths, and dry biomass of sunn hemp planted in high Cd-contaminated soil. The Cd concentration in the leaves of sunn hemp inoculated with S. cyaneus (73.82 ± 2.20 mg kg^-1 plant dry wt) was higher than that of plants with S. rapamycinicus inoculation and the uninoculated control. The phytoextraction of Cd by sunn hemp was significantly increased with Cd-resistant Streptomyces inoculation. In conclusion, both strains of Cd-resistant Streptomyces had potential on enhancing Cd phytoextraction efficiency of sunn hemp. Our study suggests the application of Cd-resistant Streptomyces can improve Cd phytoextraction by sunn hemp for restoration of Cd-polluted sites.

Hazards related to the presence of cadmium in food - Studies on the European soil centipede, Lithobius forficatus

The soil is an environment rich in numerous potentially toxic substances/elements when present at elevated concentrations. They can be transported through the successive levels of the trophic chain. Animals living in a contaminated environment or eating contaminated food can accumulate potentially toxic elements in their bodies. One of the potentially toxic metals is cadmium, which accumulates significantly in soils. The aim of our research was to evaluate the changes caused by cadmium supplied with the food administered to invertebrates living in uncontaminated soil. The results were compared with those obtained for animals raised in contaminated soil, where cadmium entered the body via the epidermis. As the material for studies, we chose a common European soil centipede, Lithobius forficatus. Adult specimens were divided into the following experimental groups: C - control animals, Cd12 and Cd45 - animals fed with Chironomus larvae maintained in water containing 80 mg/l CdCl₂, for 12 and 45 days, respectively. The material was analyzed using qualitative and quantitative analysis (transmission electron microscopy, confocal microscopy, flow cytometry, atomic absorption spectrometry). Eventually, we can conclude that the digestive system is an effective barrier against the effects of toxic metals on the entire organism, but among the gonads, ovaries are more protected than testes, however, this protection is not sufficient. Accumulation of spherites and mitochondrial alterations are probably involved in survival mechanisms of tissues after Cd intoxication.

Association of gut microbiota characteristics and metabolites reveals the regulation mechanisms under cadmium consumption circumstance

BACKGROUND

Cadmium is a non-biodegradable heavy metal with a long biological half-life. Although its negative impact on human health has been previously reported, the association of cadmium consumption overdose with changes in the gut microbiota and its corresponding metabolites has not been fully elucidated so far.

RESULTS

Cadmium consumption overdose led to a reduced body weight gain accompanied by an enhanced level of the proinflammatory cytokine tumor necrosis factor-α, interleukin-6, and histamine in the serum of the rats in comparison with normal rats. Furthermore, hepatotoxicity was also observed to be induced by cadmium, which was consistent with abnormal hepatic activities of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase and oxidative stress. In contrast, Lactobacillus rhamnosus-fermented Ganoderma lucidum (FGL) slice supplementation improved the aforementioned physiological properties. More importantly, microbiome and metabolites analysis indicated cadmium exposure significantly reduced the generation of short-chain fatty acids in the gut, particularly butyrate. However, rats in the FGL group had the highest level of butyrate in the feces, characterized with significantly enriched probiotics (Lactobacillus, Bifidobacterium) and butyrate-producing bacteria (Roseburia).

CONCLUSION

The targeted regulation of the gut microbial community and its metabolites might be the essential association for attenuating body dysfunction induced by cadmium. The supplementation of FGL, as evidenced in this study, might highlight a novel approach to this field. © 2022 Society of Chemical Industry.

Interactions of Ingested Polystyrene Microplastics with Heavy Metals (Cadmium or Silver) as Environmental Pollutants: A Comprehensive In Vivo Study Using Drosophila melanogaster

Living organisms are now constantly exposed to microplastics and nanoplastics (MNPLs), and besides their toxic potential, they can also act as carriers of various hazardous elements such as heavy metals. Therefore, this study explored possible interactions between polystyrene microplastics (PSMPLs) and two metal pollutants: cadmium chloride (CdCl2) and silver nitrate (AgNO3). To better understand the extent of biological effects caused by different sizes of PSMPLs, we conducted in vivo experiments with five doses (from 0.01 to 10 mM) that contained polystyrene particles measuring 4, 10, and 20 µm in size on Drosophila larvae. Additional experiments were performed by exposing larvae to two individual metals, CdCl2 (0.5 mM) and AgNO3 (0.5 mM), as well as combined exposure to PSMPLs (0.01 and 10 mM) and these metals, in an attempt to gain new insight into health risks of such co-exposure. Using transmission electron microscopy imaging, we managed to visualize the biodistribution of ingested PSMPLs throughout the fly's body, observing the interactions of such plastics with Drosophila intestinal lumen, cellular uptake by gut enterocytes, the passage of plastic particles through the intestinal barrier to leak into the hemolymph, and cellular uptake by hemocytes. Observations detected size and shape changes in the ingested PSMPLs. Egg-to-adult viability screening revealed no significant toxicity upon exposure to individual doses of tested materials; however, the combined exposure to plastic and metal particles induced aggravated genotoxic effects, including intestinal damage, genetic damage, and intracellular oxidative stress (ROS generation), with smaller sized plastic particles + metals (cadmium and silver) causing greater damage.

White adipose tissue as a target for cadmium toxicity

Cadmium (Cd) is a widespread heavy metal known as a toxic environmental pollutant. Cd exposure is threatening due to its bioaccumulation trait in living systems that exceeds 35 years without a beneficial biological role. Acute exposure to high Cd doses was reported to impact adipose tissue (AT) function adversely. The main aim of this study is to investigate the effect of low-dose chronic Cd exposure on the genes involved in adipose tissue (AT) functions. Adult male Sprague-Dawley rats were exposed to a low Cd dose (15 mg/kg B.W./day) for 10 weeks. Then, three AT depots-subcutaneous AT (SUB-AT), abdominal AT (AB-AT), and retroperitoneal AT (REtrop-AT) were excised for Cd accumulation measures and gene expression analysis. Adiponectin and leptin gene expression levels were investigated as markers for adipocytes function and homeostasis. Our results showed that Cd accumulated in all the tested adipose depots, but SUB-AT was found to be the depot to most accumulate Cd. Also, it was exhibited that chronic exposure to low Cd doses altered the gene expression of adipocytokines. The levels of adiponectin and leptin mRNA expression were downregulated in all tested AT-depots after Cd exposure. The significant adverse effect on SUB-AT compared to other depots indicates different responses based on AT depots location toward Cd exposure. Collectively, these results suggest a toxic effect of Cd that influenced adipocyte function.

Rice Plants (Oryza sativa L.) under Cd Stress in Fe Deficiency Conditions

Due to the environment pollution by cadmium (Cd) near industrial metallurgic factories and the widespread use of phosphorus fertilizers, the problem of toxic Cd effect on plants is well discussed by many authors, but the phytotoxicity of Cd under iron (Fe) deficiency stress has not been sufficiently studied. The aim of the work was to study comprehensively the effect of Cd under Fe deficiency conditions on physiological, biochemical, and anatomical parameters of rice varieties, to identify varietal differences in plant response to the effect of double stress. Relative resistance and sensitivity to the joint effect of Cd and Fe deficiency stress rice varieties have been identified. Double stress decreased a linear growth and biomass accumulation of roots and shoots (by 36-50% and 33-46% and 32-56% and 32-48%, accordingly), content of photosynthetic pigments (Chla, Chlb, and carotenoids by 36-51%, 32-47%, and 64-78%, accordingly), and relative water content (by 18-26%). Proline content increased by 28-103% in all rice varieties, but to a lesser extent in sensitive varieties. The thickness of the lower and upper epidermis and the diameter of vascular bundles of leaves decreased by 18-50%, 46-60%, and 13-48%, accordingly. The thickness of the root endodermis and exodermis and diameter of the central cylinder mainly decreased. The thickness of the exodermis increased slightly by 7%, and the diameter of the central cylinder remained at the control level in resistant Madina variety while in sensitive Chapsari variety, these indicators decreased significantly by 50 and 45%, accordingly. Thus, the aggravation of adverse effect of Cd under Fe deficiency conditions and the varietal specificity of plants' response to double stress were shown. It creates the need for further study of these rice varieties using Fe to identify mechanisms for reducing the toxic effect of Cd on plants as well as the study of Fe and Cd transporter genes at the molecular level.

Probabilistic Risk Assessment of Dietary Exposure to Cadmium in Residents of Guangzhou, China-Young Children Potentially at a Health Risk

Cadmium (Cd) and its compounds are hazardous environmental pollutants with renal toxicity and human carcinogenicity, with ingestion of contaminated foods representing the major mode of exposure. There have been a number of reports evaluating the Cd content in various foods; however, regarding the actual risk posed by dietary cadmium exposure, only a few reports are available in which single point evaluation (less accurate than multiple point evaluation) was employed. In this study, we used a margin of exposure (MOE) model and @RISK software (for multiple evaluation) to evaluate Cd-related health risk in the local Guangzhou residents at varying ages, through a comparison between the estimated monthly exposures and the provisional tolerable monthly intake (0.025 mg/kg body weight (b.w.)), based on the Cd contents in various food categories available locally (a total of 3964 food samples were collected from each of the 13 districts of Guangzhou between 2015 and 2019), which were determined by using inductively coupled plasma mass spectrometry. In this study, Cd was detected in 69.6% of the samples (averaged 0.120 mg/kg), and rice and its products, leafy vegetables, bivalves, and shrimp and crabs contributed most to Cd exposure (8.63, 3.18, 2.79, and 1.48 ng/kg b.w./day, respectively). The MOE values demonstrated the following tendency: the younger age group, the lower MOE, and its 95% confidence range for the (youngest) 3~6 year old group started from 0.92, indicating a health risk of young children, while that for the other age groups were all above 1.0. Our preliminary findings warrant further clarification using biomarker assays in the relevant population.

The Response of Thiols to Cadmium Stress in Spinach (Spinacia Oleracea L.)

The aim of this study is to examine the thiol species for the high cadmium (Cd) tolerance of spinach and provide information for the improvement of soil utilization. The spinach was cultured in aqueous solution with concentrations of Cd ranging from 1 to 9 mg/L. The time responses of glutathione (GSH) and phytochelatins (PCs, PC2-PC4) in the tissues of spinach were monitored via HPLC−MS/MS, and the concentrations of Cd in the roots, shoots and leaves were detected by ICP−OES. Data were analyzed via one-way ANOVA and Spearman correlation to assess the relationships among the types of thiols and the changes between types of thiols and Cd. As Cd stress increased, Cd concentrations in tissues also increased. The total thiol contents responded to Cd stresses with correlations r ranging from 0.394 (root), 0.520 (shoot) to 0.771 (leaf) (p < 0.01). GSH and PC3 were dominant on most of the days under Cd stress. The correlation r between improvements in GSH and increments of Cd concentration in roots was −0.808 (p < 0.01), and r between changes in PC3 and changes in Cd concentrations in leaves was −0.503 (p < 0.01). No correlation can be found between GSH and the subtypes of PCs in shoots, but strong positive correlations within the subtypes of PCs. Thiols can be produced in different tissues of spinach, while the shoots are only a transport tissue for GSH.

Applications of Smartphone-Based Aptasensor for Diverse Targets Detection

Aptamers are a particular class of functional recognition ligands with high specificity and affinity to their targets. As the candidate recognition layer of biosensors, aptamers can be used to sense biomolecules. Aptasensors, aptamer-based biosensors, have been demonstrated to be specific, sensitive, and cost-effective. Furthermore, smartphone-based devices have shown their advantages in binding to aptasensors for point-of-care testing (POCT), which offers an immediate or spontaneous responding time for biological testing. This review describes smartphone-based aptasensors to detect various targets such as metal ions, nucleic acids, proteins, and cells. Additionally, the focus is also on aptasensors-related technologies and configurations.

Response of glutathione pools to cadmium stress and the strategy to translocate cadmium from roots to leaves (Daucus carota L.)

Carrots are one of the most highly consumed vegetables in the world. Due to the large area of cadmium (Cd) contaminated farmland, to abate the impact of Cd contamination on carrot quality and safety, a novel strategy is required to drive Cd translocation from the soil to the overground leafy tissues of carrots to protect the edible roots and thus ensure food security. To this end, this article presents an experimental study with mathematical models to assess the tolerance and accumulation capacity of Cd in inedible carrot leaves, as well as the regulatory factors affecting Cd distribution in carrots. The glutathione (GSH) pools were examined in carrot leaves in response to the oxidation stress induced by Cd exposures, and it was found that under low Cd stress (1 and 3 mg/L) the changes of GSH pools were dominated by the variation of GSH, showing higher GSH content and low levels of oxidized GSH content (GSSG). In contrast, both of these two indicator variables as well as the GSH/GSSG ratio all decreased under high Cd stress (5 and 9 mg/L). Combining this information with Cd concentrations in leaves, a model was established to predict the Cd accumulation capacity of leaves. The data showed that the potential Cd accumulation in carrot leaves could be as high as 514 μg/kg dry weight. Furthermore, the factors and primary physiological indicators affecting and regulating GSH pools by multiple stepwise regression were analyzed. The results showed that increasing chlorophyll a/b ratio and γ-glutamylcyclotransferase activity while inhibiting phytochelatin synthase activity could expand the tolerance of carrot leaves to Cd. These findings suggest a possible strategy for regulating the distribution of toxic metals in plants through a molecular-based approach and provide some important information that could be conducive to achieving food safety and phytoremediation of contaminated soils.

Cadmium Body Burden and Inflammatory Arthritis: A Pilot Study in Patients from Lower Silesia, Poland

The purpose of this study was to determine the relationship between cadmium exposure and the likelihood of developing or exacerbating symptoms of inflammatory arthritis (IA). The study included 51 IA patients and 46 control subjects. Demographic and lifestyle data were collected. Haematological and biochemical parameters and blood cadmium levels (Cd-B) were determined. Cd-B correlated positively with age, smoking, living in a high-traffic area, and serum levels of inflammatory markers and negatively with mean corpuscular haemoglobin concentration (MCHC). The binary logistic regression model implied that high Cd-B (≥0.65 μg/L) is linked with an increased risk of IA in the studied population (odds ratio: 4.4). High levels of DNA oxidative damage marker (8-hydroxy-2'-deoxyguanosine) (≥7.66 ng/mL) and cyclooxygenase-2 (≥22.9 ng/mL) and frequent consumption of offal was also associated with increased risk of IA. High Cd-B was related to increased risk of disease symptoms onset in the group of IA patients, decreased the level of interleukin 10, and positively correlated with the disease activity. Increased Cd-B is associated with intensified inflammatory processes and decreased haemoglobin levels; in IA patients with decreased anti-inflammatory interleukin 10. These changes partly explain why cadmium exposure and a high cadmium body burden may raise the risk of IA and of disease symptoms exacerbation.