The vadose zone acts as a natural buffer that prevents contaminants such as arsenic (As) from contaminating groundwater resources. Despite its capability to retain As, our previous studies revealed that a substantial amount of As could be remobilized from soil under repeated wet-dry conditions. Overlooking this might underestimate the potential risk of groundwater contamination. This study quantified the remobilization of As in the vadose zone and developed a prediction model based on soil properties. 22 unsaturated soil columns were used to simulate vadose zones with varying soil properties. Repeated wet-dry cycles were conducted upon the As-retaining soil columns. Consequently, 13.9-150.6 mg/kg of As was remobilized from the columns, which corresponds to 37.0-74.6 % of initially retained As. From the experimental results, a machine learning model using a random forest algorithm was established to predict the potential for As remobilization based on readily accessible soil properties, including organic matter (OM) content, iron (Fe) content, uniformity coefficient, D30, and bulk density. Shapley additive explanation analyses revealed the interrelated effects of multiple soil prop-erties. D30, which is inter-related with Fe content, exhibited the highest contribution to As remobilization, fol-lowed by OM content, which was partially mediated by bulk density.

Arsenic exposure has been implicated in various malignancies, including head and neck cancers (HNCs). However, the association between arsenic exposure and HNC development remains unclear. This systematic review aimed to assess the relationship between arsenic exposure and the risk of developing HNCs. This study adhered to PRISMA guidelines. A systematic search of PubMed, Embase, Scopus, and Web of Science was conducted from inception to January 2025 to identify relevant studies. Observational studies reporting the association between arsenic and HNCs were included. Two independent reviewers performed study selection, data extraction, and risk of bias assessment using the NIH criteria. A total of 24 studies met the eligibility criteria, including 35,641 cases and 4,631 controls. The mean age of cases was 50.3 years, while controls had a mean age of 57.7 years. Nineteen studies assessed nasopharyngeal/laryngeal cancers, and 13 investigated oral cancers. Environmental/occupational arsenic exposure was reported in 14 studies, while 11 studies measured arsenic levels in biological samples. Geographical differences in exposure outcomes were observed, with significant associations reported in studies from Tunisia, Chile, Brazil, and Taiwan, while studies from the UK, Finland, and a multicenter European study found no significant relationship. Blood, hair, soil, and drinking water arsenic concentrations varied across studies, with inconsistent findings. The findings suggest a potential link between arsenic exposure and HNCs, particularly in regions with high environmental contamination. However, heterogeneity in exposure assessment and study design limits definitive conclusions. Further well-controlled studies are needed to clarify the association and underlying mechanisms.

BackgroundSoybean (Glycine max L. Merrill), a vital source of edible oil and protein, ranks seventh in global agricultural production, yet its productivity is significantly hindered by potential toxic metal/liods (PTM) stress. Arsenic (As), a highly toxic soil contaminant, poses substantial risks to both plants and humans, even at trace concentrations, particularly in China.ResultsThis research endeavor delves into the combined effect of arsenate (AsV), a common form of As in soil, and nano-selenium (nSe), on the transcriptional regulation of key genes and the modulation of signaling and metabolic cascades in young soybean seedlings. Our findings indicate that nSe mitigates AsV toxicity by modulating hormonal signaling cascades, particularly the phenylalanine and salicylic acid pathways, thereby augmenting antioxidant defenses and mitigating the damaging effects of reactive oxygen species (ROS) on soybean roots.ConclusionThis study offers valuable insights into the molecular mechanisms underlying metalloid tolerance in soybean, opening avenues for the development of strategies to bolster As resistance in contaminated soils. Nevertheless, further investigation is imperative to elucidate the intricate interplay of hormonal signaling in soybean roots during nSe supplementation under As stress conditions.

Soil contamination with arsenic (As) is becoming a serious concern for living organisms. Arsenic is a nonessential metalloid for plants, humans, and other living organisms. Biochar (BC) is a very effective amendment to remediate polluted soils and it received great attention owing to its appreciable results. Arsenic toxicity negatively affects plant morph-physiological and biochemical functioning and upsurges the generation of reactive oxygen species (ROS), which negatively affect cellular structures. Arsenic toxicity also reduces seed germination and impedes plant growth by decreasing nutrient uptake, causing oxidative damage and disrupting the photosynthetic efficiency. Plants use different strategies like antioxidant defense and increased osmolyte synthesis to counteract As toxicity; nevertheless, this is not enough to counter the toxic impacts of As. Thus, applying BC has shown tremendous potential to counteract the As toxicity. Biochar application to As-polluted soils improves water uptake, maintains membrane stability and nutrient homeostasis, and increases osmolyte synthesis, gene expression, and antioxidant activities, leading to better plant performance. Additionally, BC modulates soil pH, increases nutrient availability, causes As immobilization, decreases its uptake and accumulation in plant tissues, and ensures safer production. The present review describes the sources, toxic impacts of As, and ways to lower As in the environment to decrease its toxic impacts on humans, the ecosystem, and the food chain. It concentrates on different mechanisms mediated by BC to alleviate As toxicity and remediate As-polluted soils and different research gaps that must be fulfilled in the future. Therefore, the current review will help to develop innovative strategies to minimize As uptake and accumulation and remediate As-polluted soils to reduce their impacts on humans and the environment.

Arsenic (As) in soil, such as mining waste, is a concern for communities with legacy contamination. While the chronic health effects of As exposure through drinking water are well documented, the association between As in soil and population-wide health impacts is complex, involving factors like soil accessibility, soil properties, and exposure modes. This review summarizes evidence of associations between As in soil and human health, as well as biomarker and bioaccessibility evidence of exposure pathways. Fourteen studies were included in the final analysis. Reviewed studies reported associations between As in soil and birth outcomes, neurological effects, DNA damage, and cancer. Some of these health outcomes are not known to be linked to As in drinking water and were reported over a range of soil concentrations, indicating inconsistencies. Higher soil As concentrations are associated with higher As in human biospecimens, suggesting direct and indirect soil ingestion as primary exposure pathways. The subpopulations more likely to be exposed include younger children and those involved in soil-based activities. Future research should focus on standardized epidemiological studies, longitudinal studies, soil exposure and mitigating factors, combined exposure biomarker studies, the behavior of the different As species, soil dose related to bioavailability/bioaccessibility, and effects with other elements.

Regulations on chemicals aim to protect public health and the environment. However, owing to the nature of this chemical, it is difficult to determine its impact pathway. Thus, it is difficult to investigate the damage caused by chemicals. However, it is essential to evaluate the costs and benefits of chemicals to establish reasonable chemical regulations. Therefore, this study analyzes the benefits of strengthening the regulation of chemical substances in Korea using the conditional valuation method. In particular, this study evaluated the public benefit of the chemical regulation of arsenic, which is a carcinogen. Data were collected from 1000 households in Korea, and a one-and-one-half-bound dichotomous choice spike model was used. The results show that the average annual willingness to pay for additional income tax payments over 10 years to reduce the incidence of arsenic-related diseases is 4314 Korean won (3.67 USD), with 57.5% of households refusing to pay. Additional analysis indicates that females are more willing to pay, and a higher education level, knowledge of arsenic, and experience in using arsenic-free products and hand sanitizers lead to a higher willingness to pay. The results of this study can be used to establish an efficient level of arsenic regulations and determine their effect on the related market.

This study investigates the role of 24-epibrassinolide (BR, 10- 2 mu M) in mitigating arsenic (As)-induced stress in maize (Zea mays L. cv. 704). Seedlings were exposed to As at concentrations of 0, 5, 10, 25, 50, 100, and 250 mu M, with or without BR application. Arsenic exposure increased oxidative damage markers such as MDA and H2O2 while BR treatment significantly enhanced antioxidant enzymes activities including ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), glutathione reductase (GR) and glutathione Stransferase (GST), reducing reactive oxygen species (ROS) levels, and minimizing oxidative damage. Additionally, BR significantly increased proline, phenolic compounds, flavonoids, and soluble sugars, contributing to osmoprotection and stress tolerance, as well as enhancing FRAP and DPPH antioxidant activities. Furthermore, BR increased amino acids (AAs) such as proline (Pro), cysteine (Cys), glutamine (Gln), and glutamate (Glu). Gene expression analysis revealed significant upregulation of detoxification-related genes including cytochrome P450 monooxygenases (CYPs), GT1, GST27 and multidrug resistance-associated proteins (MRPs) under BR treatment. These findings suggest that BR enhances maize tolerance to As toxicity by activating detoxification pathways, improving antioxidant defense, and stabilizing metabolic processes. The results underscore the potential application of BR in sustainable agriculture to improve crop resilience in As-contaminated soils.

Contamination of vegetables with heavy metals and microplastics is a major environmental and human health concern. This study investigated the role of taurine (TAE) in alleviating arsenic (As) and polyvinyl chloride microplastic (MP) toxicity in broccoli plants. The experiment followed a completely randomized design with four replicates per treatment. Plants were grown in soil spiked with MP (200 mg kg-1), As (42.8 mg kg-1), and their combination (As + MP) with or without taurine (TAE; 100 mg L-1) foliar supplementation. Results demonstrated that MP, As, and As + MP toxicity markedly decreased growth, chlorophyll content, photosynthesis, and nutrient uptake in broccoli plants. Exposure to individual or combined MP and As increased oxidative damage, indicated by elevated methylglyoxal (MG), superoxide radical (O2 & sdot;-), hydrogen peroxide (H2O2), hydroxyl radical (& sdot;OH), and malondialdehyde (MDA) levels alongside intensified lipoxygenase (LOX) activity and leaf relative membrane permeability (RMP). Histochemical analyses revealed higher lipid peroxidation, membrane damage as well as increased H2O2 and O2 center dot- levels in the leaves of stressed plants. Micropalstic and As toxicity deteriorated anatomical structures, with diminished leaf and root epidermal thickness, cortex thickness, and vascular bundle area. However, TAE improved the antioxidant enzyme activities, endogenous ascorbate-glutathione pools, hydrogen sulfide and nitric oxide levels that reduced H2O2, O2 & sdot;-, & sdot;OH, RMP, MDA, and activity of LOX. Taurine elevated osmolyte accumulation that protected membrane integrity, resulting in increased leaf relative water content and plant biomass. Plants supplemented with TAE demonstrated improved anatomical structures, resulting in diminished As uptake and its associated phytotoxicity. These findings highlight that TAE improved redox balance, osmoregulation, ion homeostasis, and anatomical structures, augmenting tolerance to As and MP toxicity in broccoli.

Arsenic (As) contamination in soil represents a major challenge to global agriculture, threatening crop productivity and food security, making the development of effective mitigation strategies essential for sustainable farming. Synthetic bacterial communities (SynCom) improve host plants ability to withstand As stress by several mechanisms. It is well known that polyamines (PAs) strengthen the antioxidant defence system, prevent ethylene formation, preserve cell pH, and shield plant cells from the damaging effects of As, and so forth; nevertheless, it is still unknown how SynCom modify PA metabolism to improve plant resistance to As. Pot experiment was carried out to evaluate how SynCom affects root PA homeostasis, hydrogen peroxide (metabolite associated with PA), genes encoding antioxidant system and expression and activities of PA- associated degrading and synthesizing enzymes in rice subjected to As. SynCom inoculated plants exhibited maximum growth attributes, gene expression of two plasma membrane intrinsic protein, leaf water potential, and chlorophyll contents than non-inoculated plants exposed to As stress. With increased activity of PA catabolic enzymes (copper-containing diamine oxidase, CuAO; polyamine oxidase, PAO) and putrescine synthases (ornithine decarboxylase; arginine decarboxylase, ADC), SynCom inoculated plants resulted in higher putrescine and cadaverine concentrations but lower spermidine and spermine contents. Under As stress, the SynCom inoculated plants resulted in up-regulation of spermine synthase gene, OsSPMS, and down-regulation of PA catabolic enzyme genes (OsCuAO6, OsCuAO8, OsCuAO1 and OsCuAO2) and PA synthase genes (OsADC2 and OsADC1). As stressed plants inoculated with SynCom had higher level of expression in OsPAO1, OsPAO2, OsPAO3 as compared to non-inoculated plants, stimulating reactive oxygen species-associated stress responsiveness signaling through low H2O2 levels by enhancing the genes encoding antioxidant defence system (OsCu/Zn-SOD, OsCAT1 and OsMn-SOD). The results of this study showed that SynCom can alter PA metabolism to improve plants' resistance to heavy metals like As. The inoculation of SynCom emerges as a promising strategy to enhance plant resilience against As toxicity by promoting positive interactions and regulatory stress-responsive pathways. Furthermore, the inoculation of SynCom is a viable approach capable of ameliorating heavy metal stress and improving the productivity of crops in the contaminated soil by fostering positive interactions and stress responsive regulatory mechanisms. (c) 2025 SAAB. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Arsenic (As) is a toxic metal that can harm plants by causing oxidative stress, stunting growth, and disrupting metabolism. This study investigates the potential effect of gamma-aminobutyric acid (GABA) and salicylic acid (SA) in mitigating the toxic effects of As on sunflower plants. The aim is to enhance growth, improve metabolite accumulation, strengthen antioxidant defenses, reduce oxidative stress, enhance nutrient status, and minimize As uptake in sunflower plants. To investigate the effect of GABA and SA on arsenic toxicity, two sunflower genotypes (FH-779 and FH-773) were exposed to arsenic at a concentration of 60 mg kg(-)(1) in the soil. The experimental design followed a completely randomized design with three replications of each treatment arranged in a factorial manner. The sunflower plants were treated with foliar sprays of GABA (200 mg L--(1)), SA (100 mg L--(1)), and a combination of both GABA + SA (200 + 100 mg L--(1)). Both FH-779 and FH-773 genotypes exhibited significant accumulation of As + 5 and As+ 3 in roots and leaves, resulting in reduced nutrient uptake. GABA, SA, and GABA + SA treatments alleviated As-induced oxidative stress by reducing hydrogen peroxide (H2O2) production and malondialdehyde (MDA) levels in both genotypes. These treatments also enhanced osmolyte accumulation, improving osmotic adjustment under As stress. Additionally, GABA and SA spray enhanced the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), aiding in scavenging reactive oxygen species (ROS) and preventing oxidative damage. The combination of GABA and SA had a more pronounced effect on the translocation and remediation of As compared to GABA and SA alone. Arsenic removal efficiency reached maximum in the GABA + SA treatment in both FH-779 and FH-773 genotypes, greater than control group, respectively. The findings of this study highlight the beneficial roles of gamma-aminobutyric acid and salicylic acid in mitigating the negative effects of arsenic on growth of sunflower plants. These compounds regulate photosynthetic pigments, osmotic pressure, and antioxidant defense systems, improve nutrient status, and reduce arsenic uptake. Salicylic acid and gamma-aminobutyric acid show potential for alleviating stress in other crops facing abiotic stress. This study highlights the impact of these compounds on plant defense mechanisms in stress conditions, providing a promising approach to reduce arsenic toxicity in crops, thereby improving agricultural productivity in contaminated environments.