Cd In Tissues Research Articles

Heavy Metal Deposits in Toilet Tissues Sold in Markets within Enugu Metropolis, Enugu State

Studies were carried out to assess the deposits of selected heavy metals (Pb and Cd) in toilet tissues sold in markets within the Enugu metropolis, Enugu State using standard analytical procedures and instrumentation. The samples underwent digestion and were subsequently analyzed for heavy metals using an atomic absorption spectrophotometer. Toilet tissue samples A, B, C, and D had mean Pb values of 0.121±0.071, 0.258±0.040, 0.205±0.076, and 0.302±0.014 µg/g respectively. The mean Cd levels in the toilet tissue samples A, B, C, and D were 0.062±0.022, 0.037±0.008, 0.097±0.005, and 0.012±0.002µg/g respectively. The mean values of the investigated heavy metals were statistically significant in the studied toilet tissue samples. The toilet tissue samples, whether of high quality or low quality, poorly packaged or well packaged, had mean values of the studied metals within the recommended threshold limits.

Arbuscular Mycorrhizal Fungi-Assisted Phytoremediation: A Promising Strategy for Cadmium-Contaminated Soils

Arbuscular mycorrhizal fungi (AMF) have been shown to play a major role in regulating the accumulation, transport, and toxicity of cadmium (Cd) in plant tissues. This review aims to highlight the current understanding of the mechanisms by which AMF alleviate Cd toxicity in plants. Cd accumulation in agricultural soils has become an increasing global concern due to industrial activities and the use of phosphatic fertilizers. Cd toxicity disrupts various physiological processes in plants, adversely affecting growth, photosynthesis, oxidative stress responses, and secondary metabolism. AMF alleviate Cd stress in plants through multiple mechanisms, including reduced Cd transport into plant roots, improved plant nutritional status, modulation of organic acid and protein exudation, enhanced antioxidant capacity, and maintenance of ion homeostasis. AMF colonization also influences Cd speciation, bioavailability, and compartmentalization within plant tissues. The expression of metal transporter genes, as well as the synthesis of phytochelatins and metallothioneins, are modulated by AMF during Cd stress. However, the efficacy of AMF in mitigating Cd toxicity depends on several factors, such as soil properties, plant species, AMF taxa, and experimental duration. Further knowledge of the intricate plant–AMF–Cd interactions is crucial for optimizing AMF-assisted phytoremediation strategies and developing Cd-tolerant and high-yielding crop varieties for cultivation in contaminated soils.

Cadmium bioavailability in market nori and kelp: A comparison with rice and mechanisms underlying reduction in rice cadmium bioavailability with nori and kelp consumption

Seaweeds, despite being rich in beneficial substances, also contain toxic metals such as cadmium (Cd), leading to ongoing debates about their health impacts. This study assessed the risk of Cd exposure from consuming nori and kelp, as well as the potential benefits of these seaweeds in mitigating Cd exposure from rice, using mouse bioassays. The results indicated that all test nori samples (n = 35) had Cd concentration exceeding 1.2 μg g−1, while the majority of kelp samples (18 out of 24) contained <0.5 μg g−1. When mixed with Cd-free rice at a 5 % (w/w) ratio and administered to mice for 14 days, kelp samples with 0.36 and 0.50 μg g−1 Cd (Kelp-0.36 and Kelp-0.50) did not result in Cd accumulation in the liver or kidneys. Conversely, nori samples with 1.30 and 1.67 μg g−1 Cd (Nori-1.30 and Nori-1.67) led to significant Cd accumulation, highlighting the exposure risk associated with nori. This risk was further emphasized by a doubling of Cd accumulation in the tissues of mice fed sushi containing nori compared to those fed sushi without nori. However, the Cd accumulation from consuming Nori-1.30 and Nori-1.67 was comparable to that from rice with a lower Cd concentration (0.93 μg g−1), suggesting a lower bioavailability of Cd in nori than in rice. More promisingly, when consumed with Cd-containing rice at a 5 % (w/w) ratio, Kelp-0.36, Kelp-0.50, Nori-1.30, and Nori-1.67 reduced the accumulation of rice Cd in mouse tissues by 25.8 %–48.1 %, primarily by increasing the relative abundances of Bacteroides in the gut of mice and enhancing fecal output, which in turn increased the excretion of rice-derived Cd by 1.46–1.54 times. These findings suggest that kelp consumption may be relatively safe, while caution is advised for nori. Moreover, regular consumption of specific amounts of seaweeds, particularly kelp, could help to reduce Cd exposure from rice.

Pollution assessment, ecological risk and source identification of heavy metals in paddy soils and rice grains from Salem, South India

The present study investigated concentrations of metals (Cu, Zn, Fe, Mn, Ni, Pb, and Cd) in paddy soils and rice tissues of nine different widely used indica rice varieties in Salem district, India. The order of DTPA soil available metal contents (mg kg-1) were Fe (33.50) > Mn (8.86) > Cu (2.58) > Pb (1.99) > Zn (1.67) > Ni (1.48) > Cd (0.13). Pollution load index (PLI) levels for Cd (1.28) were ‘moderately polluted’, contamination factor (CF) and enrichment factor (EF) values for all metals showed ‘medium contamination’ and ‘less enrichment’ except for Cu and Pb. Ecological risk factor (ERF) and potential ecological risk index (PRI) values of Cd (31.94 and 287.50) showed ‘moderate risk’ and ‘strong ecological risk’. Bio-accumulation factor (BAF) levels of Cd (48.12) and Pb (27.89) are classified as ‘high concentrators’. Translocation factor (TF) values of Pb (2.9), Cd (2.5) and Ni (1.7) were greater than one for roots to plants. Children had higher target hazard quotient (THQ) and hazard index (HI) values for Cd, Pb and Ni than adults. Principal component analysis (PCA) revealed with all parameters that they fell within the two primary factors 1 and 2, with an eigenvalue of 4.69 (33.52% variation) and 3.73 (26.66% variation), respectively. However, cluster analysis (CA) revealed three distinct groups between the metals studied. Although the soil metal contents were within the permissible levels, the grain Cd (6.07 mg kg-1), Pb (56.20 mg kg-1), and Fe (116.11 mg kg-1) contents in all the rice varieties exceeded the prescribed limits of 0.4, 0.2, and 15 mg kg-1, respectively. Our findings will provide important data for metal enrichment in soils to implement more effective measures to reduce the contamination of metals in paddy fields.

Multiple-Integrated Biomarker Indexes to Assess the Responses of the Flatfish Achirus lineatus during Exposure to Light Crude Oil Water Accommodated Fraction.

In the present study, we evaluated the biological response of Achirus lineatus to water accommodated fraction (WAF) of light crude oil (American Petroleum Institute gravity 35°) during a sub-chronic bioassay (14 and 28 days) at two different concentrations: 5% v/v (1.20µg∙L- 1 expressed as total polycyclic aromatic hydrocarbons [∑25 PAH]) and 10% v/v (6.61µg∙L- 1 [∑25 PAH]). The responses were evaluated through the biomarker response index (BRI), the integrated biomarker response (IBRv2) and the bioconcentration factor (BCF). The results showed an increase in biological response in relation to WAF concentration and exposure time, which resulted in a slight and moderate disturbance in the basal condition and bioconcentration level of metals (Pb > Ni > V > Cd) in fish tissue. Results in the present study denote that flatfish such as A. lineatus may be negatively influenced by spilled light crude oil.

Engineered biochars for simultaneous immobilization of as and Cd in soil: Field evidence

Agricultural soil contamination by potentially toxic elements (PTEs) such as arsenic (As) and cadmium (Cd) poses a serious threat to food security. Immobilization serves as a widely used approach for the remediation of PTEs contaminated soils, nevertheless, the long-term effectiveness for the simultaneous immobilization of both cations and oxyanions remains a challenge. In order to effectively enhance the synergistic immobilization effect of soil As and Cd contaminated by multiple elements and improve the ecological environment of farmland. In this study, a typical polluted tailings area farmland was selected for situ immobilization experiments, and biochar was prepared from cow manure (CMB), rice straw (RSB), and pine wood (PWB) as raw materials. On this basis, the pristine biochar was modified with ferric chloride (F), potassium permanganate (K), magnesium chloride (M), and aluminum chloride (A), respectively. Furthermore, the immobilization effect of modified biochar on As-Cd and the stress effect on soil respiration were investigated. The results showed that CMB and RSB reduced the bioavailability of heavy metals, potassium permanganate has strong oxidizing properties, and the strong oxidability of potassium permanganate stimulated the generation of more oxygen-containing functional groups on the surface of biochar, thereby enhancing the adsorption and complexation effect of modified materials on As and Cd. Among them, the extracted Cd concentration of Diethylenetriamine pentaacetic acid (DTPA) in KCMB and KRSB in 2020 decreased by 8.23–43.12% and 9.67–35.29% compared to other treatments, respectively. Meanwhile, the KCMB and KRSB treatments also reduced the enrichment of As and Cd in plant tissues. In addition, the dissolved organic carbon (DOC) content in KCMB treatment was relatively high, and the carbon stability of the material was weakened. Simultaneously, the soil respiration emission of KCMB treatment was increased by 5.63% and 11.93% compared to KRSB and KPWB treatments, respectively. In addition, the structural equation also shows that DOC has a large positive effect on soil respiration. In summary, the KRSB treatment effectively achieve synergistic immobilization of As-Cd and provide important guiding significance for green and low-carbon remediation of polluted farmland.

A comparative study between the efficacy of fertigation and spraying procedures in terms of the content of Cadmium (Cd) and Arsenic (As) in greenhouse cucumber.

A comparative study between fertigation and spraying procedures in terms of the status of Cadmium (Cd) and Arsenic (As) in greenhouse cucumber was conducted as a two-factor split plot based on a randomized complete block design with three replications at the Soil and Water Research Institute, Karaj, Iran in 2023. The main and sub-factors were respectively fertigation and spraying that were used in two levels [the maximum permissible concentration of Cd and As in granular triple super phosphate fertilizer (25ppm Cd and 50ppm As) and the minimum permissible concentration of these metals in granular triple super phosphate fertilizer (5ppm Cd and 5ppm As)]. Spraying was done in three modes (spraying of leaves, leaves and fruit, and fruit). On average, the results showed that the order of the concentration of Cd in plant tissues (DW) was as leaf (0.284mg/kg) > fruit peel (0.102mg/kg) > fruit peel + flesh (0.054mg/kg) > fruit flesh (0.044mg/kg). This order for As was as leaf (0.608mg/kg) > fruit flesh (0.127mg/kg) > fruit peel + flesh (0.109mg/kg) > fruit peel (0.072mg/kg). Based on the measurements, the spraying procedure accumulated more amounts of Cd and As in the fruit (i.e., peel + flesh) than the fertigation procedure. In general, it is concluded that under soilless culture, the status of heavy metals in plant tissues of greenhouse cucumber is related to the nature of the metal, the organ exposed to the metal, and the fertilization procedure. Because there is the risk of contamination of vegetables grown in the areas fertigated and sprayed with poor-quality nutrient solutions in terms of the content of heavy metals, the frequency of fertigation and spraying needs to be monitored continuously for the quality of the vegetables cultivated in greenhouses.

Using optimized monochromatic energy dispersive X-ray fluorescence to determine the cadmium concentration in cacao and soil samples

Following the implementation of food safety limits on cadmium (Cd) in cacao products, there has been a growing demand for monitoring Cd in cacao tissues and soils. Traditional methods like acid digestion followed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are time-consuming and costly. X-ray Fluorescence is an alternative technique that offers advantages in terms of speed, cost, ease of use and less environmental impact. However, to date, relatively high detection limits have impeded its application for food safety limits. This study examines a Monochromatic Energy Dispersive X-ray Fluorescence (MEDXRF) method optimized for Cd analysis as an alternative to ICP-MS. Using a measurement time of 200 s, the average limit of quantification (LOQ) was 0.178 mg Cd kg−1 for biological samples and 0.205 mg Cd kg−1 for soil samples. A strong correlation (y = 1.013 x + 0.003, R2 = 0.984) with ICP-MS results was found for 95 bean, 16 cacao liquor, 75 leaf, and 91 soil samples. The coefficient of variation (CV) among three replicates was below the threshold value of 15 % for most samples with Cd concentrations above the reported LOQ values. Additionally, a significant difference in CV was obtained between soils sieved over 500 μm (median 8.2 %) or 2 mm (median 9.8 %). However, no significant difference in CV was observed between 500 μm unpeeled beans and cocoa liquor with particle size of 20 μm. Based on our data, the proposed procedure is to analyze three replicates for 200 s with a sample size of 500 μm. The optimized MEDXRF technique offers important advantages in terms of cost-effectiveness and efficiency of routine Cd monitoring in the cacao supply chain, large-scale screening, and scientific research, and could be extended to other crops and heavy metals that are subject to food safety regulation at low concentrations.

Bladder cancer associated with elevated heavy metals: Investigation of probable carcinogenic pathways through mitochondrial dysfunction, oxidative stress and mitogen-activated protein kinase

ObjectiveCarcinogenic mechanisms of heavy metals/ trace elements (HMTE) in bladder cancer (BC) are exactly unknown. Mitochondrial dysfunction (MD), oxidative stress (OS), and mitogen-activated protein kinases (MAPK) are probable carcinogenic mechanisms. The purpose is to investigate probable carcinogenic pathways of HMTE in BC using six MD genes, seven OS markers, and p38-MAPK. MethodsStudy included 125 BC/radical cystectomy (RC) patients between October 2020 and October 2022, and 72 controls. Exclusion criteria included previous neoplasm, chemo- or radiotherapy. Two samples (cancer/noncancer) were taken from RC specimens. Tissues/plasma/urine cadmium (Cd), lead (Pb), cobalt (Co), nickel (Ni), strontium (Sr), aluminium (Al), zinc (Zn), boron (B) were measured by ICP-OES. Tissue MD genes (mt-CO3, mt-CYB, mt-ATP 6, mt-ATP8, mt-CO1, mt-ND1), and serum OS markers (8-OHdG, MDA, 3-NT, AGEs, AOPP, ROS, SOD2), p38-MAPK were assessed by RT-PCR, and ELISA, respectively. ResultsBC and adjacent tissue showed higher (Al, Co, Pb, Ni, Zn, Cd,Sr), lower B concentrations, compared to controls. High tissue concentrations (Cd, Co, Pb, Ni, Sr) were associated with higher MD genes, OS, MAPK and lower SOD2 levels. The same differences were greater in 41 patients with concomitant elevation of two or more HMTE. Noninclusion of BC-related oncogenes (e.g. RAS) is a limitation. ConclusionsEvidence suggests that high BC tissue (Cd, Co, Pb, Ni, Si) concentrations are associated with over-expressed MD genes, OS, p38-MAPK and low SOD2. These findings provide important understanding keys of probable carcinogenic pathways in BC associated with HMTE. So, efforts should be performed to minimize and counteract exposure to toxic HMTE.

Different stoichiometric ratios of Ca and Cd affect the Cd tolerance of Capsicum annuum L. by regulating the subcellular distribution and chemical forms of Cd

The effect of calcium (Ca)–cadmium (Cd) interactions on the plant Cd bioaccumulation process may be closely related to the ecological Ca/Cd stoichiometry in the substrate. However, owing to the complexity of plant absorption, accumulation mechanisms and influencing factors, the mechanism of Ca-mediated Cd bioaccumulation and Cd tolerance in Capsicum is still unclear. In this study, the bioaccumulation, subcellular distribution and chemical forms of Cd in Capsicum were analysed via pot experiments to reveal the Ca-mediated Cd bioaccumulation process and its detoxification mechanism under different Ca/Cd stoichiometric ratios. The results revealed that an increase in the substrate Ca/Cd ratio promoted the accumulation of Cd in the roots; restricted the transport of Cd to the stems, leaves and peppers; and promoted the accumulation of Cd in the aboveground leaves but decreased its accumulation in edible parts. Cd was enriched mainly in the cell wall and cell-soluble fraction in each tissue and was enriched in only 1 %–13 % of the organelles. The accumulation of Cd in the cell wall and cell-soluble fractions of roots treated with different Ca concentrations increased by 56.57 %–236.98 % and 64.41 %–442.14 %, respectively. The carboxyl, hydroxyl and amino groups on the root cell wall play important roles in binding and fixing Cd2+. Moreover, the increase in the Ca content also increased the proportion of pectin and protein-bound Cd (F-NaCl), insoluble phosphate-bound Cd (F-C) and insoluble oxalate-bound Cd (F-HCl) in the roots, stems and leaves and reduced the proportion of highly active chemical forms such as inorganic acid salt-bound Cd (F-E) and water-soluble phosphate-bound Cd (F-W). Our study revealed that the bioaccumulation of Cd in Capsicum was influenced by the Ca/Cd ratio and that Ca could alleviate Cd stress by regulating the subcellular distribution and chemical form ratio of Cd in different tissues where the cell wall plays an important role in Cd tolerance and detoxification.

Bangladeş'in Chattogram ve Cox's Bazar bölgesindeki çamur yengeci (Scylla serrata) ve ortam çamurundaki ağır metal konsantrasyonu

Heavy metal levels have increased due to increased industrialization, which has a negative impact on crab, an essential source of protein. This study aimed to measure the level of certain heavy metals (Pb, Cd, and Hg) in edible tissue from mud crab (Scylla serrata) and related soil collected from Chattogram and Cox's Bazar in Bangladesh. The concentration of heavy metals in mud crab and the soil were determined using an Atomic Absorption Spectrophotometer (AAS) (Model ICE 3300). While the mean values of heavy metals in crab tissue samples from Chattogram were 0.06 mg/kg for Cd and 0.45 mg/kg for Pb, in the related soil samples these values were determined as 0.52 mg/kg for Cd and 7.24 mg/kg for Pb. In Cox's Bazar, the mean Pb content was 4.1 mg/kg in related soil, but the levels of Cd and Hg were below the detection limit. In S. serrata tissues, all heavy metal concentrations were below the detection limit. The heavy metal values obtained in the study were compared with the Food and Agriculture Organization (FAO), World Health Organization (WHO), European Union (EU) and Food and Drug Administration (FDA). Results concluded that metal concentrations were within permissible limits and did not pose an immediate risk to public health or human consumption. Specifically, the measured concentration levels are considered poor when compared to national and international requirements.

Screening potential plants in the gold mining area for phytoremediation approach

Abstract Heavy metal waste can be caused by anthropogenic activity. This waste can pollute soil and water far from the source. One of the ways to immobilize the heavy metals is using a plant that can accumulate them. This research aimed to screen potential plants that can be used as remediation agents due to ASGM activity in the post-mining area. This study was conducted at PT Napal Umbar Picung (NUP), Tanggamus Regency, Lampung. The study collected the potential hyperaccumulator plant from contaminated areas. Plant samples were dried at 80°C for three days in a ventilated oven. The dried samples were powdered using the Philips Blender 5000 series into fine-grained sizes. The powder samples were analyzed using X-ray fluorescence (XRF). The highest concentrations of As, Cd, Fe, Hg, Ni, Pb, and Zn in the shoot tissues of ASGM at PT NUP were 285.8 mg/kg, 11.7 mg/kg, 258,320 mg/kg, 501.6 mg/kg, 57.4 mg/kg, 806.2 mg/kg, and 4,520 mg/kg. The results showed that the hyperaccumulator plant of Hg was Alpinia galanga. Christella sp. Chromolaena odorata, Clidemia hirta, Melastoma malabathricum, and Nephrolepis cordifolia. This study can conclude that the plants can be used as a phytoremediation approach to heavy metals contamination such as As, Cd, Fe, Ni, Pb, Zn, and especially Hg.

Bioassessment of Cd and Pb at Multiple Growth Stages of Wheat Grown in Texturally Different Soils Using Diffusive Gradients in Thin Films and Traditional Extractants: A Comparative Study.

The bioavailability of heavy metals in soil is a crucial factor in determining their potential uptake by plants and their subsequent entry into the food chain. Various methods, including traditional chemical extractants and the diffusive gradients in thin films (DGT) technique, are employed to assess this bioavailability. The bioavailability of heavy metals, particularly cadmium (Cd) and lead (Pb), is also influenced by soil texture and their concentrations in the soil solution. The primary objectives of this experiment were to compare and correlate the assessment of the Cd and Pb bioavailability using the DGT technique and traditional extractants across two soil textural classes: sandy clay loam (SCL) and clay loam (CL) at two contamination levels: aged contaminated (NC) and artificially contaminated (AC). The specific objectives included assessing the bioavailability of Cd and Pb at different growth stages of the wheat plant and correlating the DGT-based bioassessments of Cd and Pb with their concentrations in various plant parts at different growth stages. This study also compared the effectiveness of the DGT method and traditional extraction techniques in assessing the bioavailable fractions of Cd and Pb in soil. The regression analysis demonstrated strong positive correlations between the DGT method and various extraction methods. The results showed that the wheat plants grown in the AC soils exhibited lower root, shoot, and grain weights compared to those grown in the NC soils, indicating that metal contamination negatively impacts plant performance. The concentrations of Cd and Pb in the wheat tissues varied across different growth stages, with the highest levels observed during the grain filling (S3) and maturity (S4) stages. It is concluded that the in situ assessment of Cd and Pb though DGT was strongly and positively correlated with the Cd and Pb concentration in wheat plant parts at the maturity stage. A correlation and regression analysis of the DGT assessment and traditional extractants showed that the DGT method provides a reliable tool for assessing the bioavailability of Cd and Pb in soils and helped in developing sustainable soil management strategies to ensure the safety of agricultural products for human consumption.

The MYC2 and MYB43 transcription factors cooperate to repress HMA2 and HMA4 expression, altering cadmium tolerance in Arabidopsis thaliana

Cadmium (Cd) represents a hazardous heavy metal, prevalent in agricultural soil due to industrial and agricultural expansion. Its propensity for being absorbed by edible plants, even at minimal concentrations, and subsequently transferred along the food chain poses significant risks to human health. Accordingly, it is imperative to investigate novel genes and mechanisms that govern Cd tolerance and detoxification in plants. Here, we discovered that the transcription factor MYC2 directly binds to the promoters of HMA2 and HMA4 to repress their expression, thereby altering the distribution of Cd in plant tissues and negatively regulating Cd stress tolerance. Additionally, molecular, biochemical, and genetic analyses revealed that MYC2 interacts and cooperates with MYB43 to negatively regulate the expression of HMA2 and HMA4 and Cd stress tolerance. Notably, under Cd stress conditions, MYC2 undergoes degradation, thereby alleviating its inhibitory effect on HMA2 and HMA4 expression and plant tolerance to Cd stress. Thus, our study highlights the dynamic regulatory role of MYC2, in concert with MYB43, in regulating the expression of HMA2 and HMA4 under both normal and Cd stress conditions. These findings present MYC2 as a promising target for directed breeding efforts aimed at mitigating Cd accumulation in edible plant roots.

Adding mineral-enriched biochar to the rhizosphere reduces heavy metal toxicity on plants and soil microbes

In this study, a mineral-enriched (Ca and P) bagasse biochar was synthesized and characterized. The formulation of Ca and P-enriched bagasse biochar (CPB) was examined for immobilizing arsenic (As), cadmium (Cd), and lead (Pb) in rhizospheric soil. The potential of CPB to alleviate heavy metal stress on plants and soil microbial communities was also investigated. The Ca and P-enriched bagasse biochar demonstrated loading of 88 % Ca and 86 % P with improved pore volume, cation exchange capacity, and water-holding capacity. The FTIR and morphology studies demonstrated an increase in surface functionalities on biochar surface and porous morphology. CPB had 1089±21 µm particle size, 1.1 µm pore size, 0.35±0.01 mv PDI, and 20.8±0.2 mv zeta potential, and displayed no phytotoxicity. The application of the CPB in the soil significantly reduced the availability of As, Cd, and Pb in the soil and their uptake in A. paniculata. CPB application altered the subcellular distribution of As, Cd, and Pb in plant tissues. The CPB spray significantly enhanced the biomass (16–27 %), protein (8–44 %), and chlorophyll (15–61 %) contents of A. paniculata. The application of CPB in metal-contaminated soil resulted in an increased relative abundance of the phylum Proteobacteria and the genera Bacillus, Gemmata, and Sphingobium in the microbial community structure of the rhizospheric soil. The study suggested that CPB formulation can be used as a potential solution to alleviate different metal uptake and toxicity of crops planted in contaminated soil, improve rhizospheric soil quality, and reconstruct the microbial community structure.

Efficacy of Fe-Mg-bimetallic biochar in stabilization of multiple heavy metals-contaminated soil and attenuation of toxicity in spinach (Spinacia oleracea L.)

Globally, soil contamination with heavy metals (HMs) pose serious threats to soil health, crop productivity, and human health. The present investigation involved synthesis and analysis of biochar with bimetallic combination of iron and magnesium (Fe-Mg-BC). Our study evaluated how Fe-Mg-BC affects the absorption of cadmium (Cd), lead (Pb), and copper (Cu) in spinach (Spinacia oleracea L.) and remediation of soil contaminated with multiple HMs. Results demonstrated the successful loading of iron (Fe) and magnesium (Mg) onto pristine biochar (BC) derived from peanut shells. The addition of Fe-Mg-BC (3%) notably increased spinach biomass, enhancing photosynthesis, transpiration, stomatal conductance, and intercellular CO2 levels by 22%, 21%, 103%, and 15.3%, respectively. Compared to control, Fe-Mg-BC (3%) suppressed metal-induced oxidative stress by boosting levels of superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) in roots by 40.9%, 57%, 54.8 %, and in shoots by 55.5%, 65.5%, and 37.4% in shoots, respectively. The Fe-Mg-BC effectively reduced the uptake of Cd, Pb, and Cu in spinach tissues by transforming their bioavailable fractions to non-bioavailable forms. The Fe-Mg-BC (3%) significantly reduced the mobility of Cd, Pb and Cu in soil and limited the concentration of Cd, Pb, and Cu in plant roots by 34.1%, 79.2%, 47%, and shoots by 56.3%, 43.3%, and 54.1%, respectively, compared to control. These findings underscore the potential of Fe-Mg-BC as a promising amendment for reclaiming soils contaminated with variety of HMs, thereby making a significant contribution to the promotion of safer food production.

Accumulation of Heavy Metals in Blueberry (Vaccinium myrtillus L.) and Dominant Mosses (Pleurozium schreberi (Willd. ex Brid.) Mitt.) as Bioindicators of the Expressway Influence on Forest Ecosystems

The intensive use, development, and expansion of the road network is expanding the zones of direct impact of road transport on forest ecosystems. Issues related to the mobility of trace elements in forest ecosystems along motorways are very important due to the numerous environmental risks associated with the excessive accumulation of metals, the ability to migrate and accumulate in plants and animals, and the risk of transferring these elements to higher trophic levels. The aim of this article was therefore to determine the impact of road traffic on the basis of contents of trace metals Cd, Cr, Cu, Ni, Pb, and Zn and to describe the relationship of these contents in moss gametophytes and blueberry leaves taken in the vicinity of an existing and variously expanded expressway (S7, Poland, Europe). Analyses of transport impacts included the effects of distance and time of pollutant deposition and road transport on habitat and stand conditions. The highest contents of Cd, Cr, Cu, Ni, Pb, and Zn in moss tissues were found in fir stands and the contents were, respectively, 0.36 mg·kg−1, 5.91 mg·kg−1, 12.5 mg·kg−1, 3.26 mg·kg−1, 8.82 mg·kg−1, and 55.28 mg·kg−1. Mosses showed the best bioindication capacity of all of the studied ecosystem elements. The Pb, Zn, Cr, Cu, and Ni contents were particularly markedly elevated in moss tissues relative to non-anthropopressured areas and dependent on distance from the emitter (road). Blueberry proved to be a less useful bioindicator, as the contents of Cd, Cr, Cu, Ni, Pb, and Zn found were similar to the data from non-anthropopressured areas and were, respectively, 0.09 mg·kg−1, 0.98 mg·kg−1, 7.12 mg·kg−1, 2.49 mg·kg−1, 1.18 mg·kg−1, and 15.91 mg·kg−1 in fir stands and 0.04 mg·kg−1, 0.47 mg·kg−1, 6.63 mg·kg−1, 1.65 mg·kg−1, 0.72 mg·kg−1, and 17.44 mg·kg−1 in pine stands.

The adsorption and fixation of Cd and Pb by the microbial consortium weakened the toxic effect of heavy metal-contaminated soil on rice

With the rapid development of industry and agriculture, the toxicity and pollution of Cd and Pb in soil and plants are becoming increasingly severe. Microbial remediation is considered an economical and sustainable method for addressing heavy metal ion pollution. This experiment established a microbial consortium capable of efficiently adsorbing and fixing Cd and Pb. The consortium consisted of two isolated strains: the straw-degrading bacterium ZJW-6 (Cellulomonas iranensis) and the phosphate-solubilizing bacterium wj1 (Pseudomonas brassicacearum). The microbial consortium exhibited high resistance to Cd and Pb, resulting in a significant reduction in heavy metal toxicity. The minimum inhibitory concentrations of Cd and Pb for the mixed microbial consortium were 900 mg/L and 2500 mg/L, respectively. Results indicated that within seven days, the microbial consortium’s removal rates of Cd and Pb reached 94.25 % and 74 %, respectively, surpassing the removal abilities of the individual member bacteria. It also enriched the soil organic matter and produced larger aggregates to adsorb more heavy metals (Cd: 3.35 mg/kg, Pb: 86.57 mg/kg). By the 60th day, 91.2 % of Cd and 97.89 % of Pb in the soil rhizosphere had been removed, and the free Cd and Pb in plant tissues were significantly reduced. Soil aggregates, which are the basic units of soil and an important index for measuring soil structure, were improved. The microbial consortium also played a significant role in restoring the soil microbial community, mobilizing the combined action of microorganisms represented by Ramlibacter and Sphingomonas to repair heavy metal pollution and promote plant growth. This provides a new method to bioremediate metal-contaminated soil and enhance the plant growth environment.

Toxicokinetics and Mussel Watch: Addressing Interspecies Differences for Coastal Cadmium Contamination Assessment.

Bivalves are often employed for biomonitoring contaminants in marine environments; however, in these large-scale programs, unavoidably, using multiple species presents a significant challenge. Interspecies differences in contaminant bioaccumulation can complicate data interpretation, and direct comparisons among species may result in misleading conclusions. Here, we propose a robust framework based on toxicokinetic measurements that accounts for interspecies differences in bioaccumulation. Specifically, via a recently developed double stable isotope tracer technique, we determined the toxicokinetics of cadmium (Cd)─a metal known for its high concentrations in bivalves and significant interspecies bioaccumulation variability─in six widespread bivalve species including mussels (Perna viridis, Mytilus unguiculatus, Mytilus galloprovincialis) and oysters (Magallana gigas, Magallana hongkongensis, Magallana angulata). Results show that oysters generally have higher Cd uptake rate constants (ku: 1.18-3.09 L g-1 d-1) and lower elimination rate constants (ke: 0.008-0.017 d-1) than mussels (ku: 0.21-0.64 L g-1 d-1; ke: 0.018-0.037 d-1). The interspecies differences in tissue Cd concentrations are predominantly due to Cd uptake rather than elimination. Utilizing toxicokinetic parameters to back-calculate Cd concentrations in seawater, we found that the ranking of Cd contamination levels at the six sites markedly differs from those based on tissue Cd concentrations. We propose that this approach will be useful for interpreting data from past and future biomonitoring programs.

Copper, lead, and cadmium monitoring via the small-spotted catshark (Scyliorhinus canicula; Linnaeus, 1758): space-time driven variability in Western Mediterranean populations.

The philopatric and sedentary nature of female S. canicula, its high abundance as a bycatch and resilience to regular exploitation by bottom trawl fisheries and its widespread distribution, makes it a potentially good candidate as a biomonitor species. To evaluate this potential, microwave-assisted extraction (MAE) and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS) were used to analyse Pb, Cd, and Cu in muscle tissue of individuals captured in the Western Mediterranean (Alicante, Spain). A monthly assessment of the concentration of these three analytes was conducted from November 2019 to November 2020 with 300 individuals. Results showed the existence of slightly higher mean concentrations during warmer seasons for Pb and Cd with mean concentrations for Pb and Cu peaking in Autumn 2019 and during Spring 2020 in the case of Cd. Significant differences in analyte concentrations found between non-consecutive months suggested gradual variability in time. Although space-wise, time-persistent concentration hotspots were observed throughout the sample area, the magnitude of these appeared to be variable in time and should be evaluated in future studies.