Journal Description
Toxics
Toxics
is an international, peer-reviewed, open access journal on all aspects of the toxic chemicals and materials, published monthly online by MDPI.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), PubMed, PMC, Embase, CAPlus / SciFinder, AGRIS, and other databases.
- Journal Rank: JCR - Q1 (Toxicology) / CiteScore - Q2 (Chemical Health and Safety)
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 14.7 days after submission; acceptance to publication is undertaken in 2.7 days (median values for papers published in this journal in the second half of 2023).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
Impact Factor:
4.6 (2022);
5-Year Impact Factor:
4.8 (2022)
Latest Articles
Innovation of BiOBr/BiOI@Bi5O7I Ternary Heterojunction for Catalytic Degradation of Sodium P-Perfluorous Nonenoxybenzenesulfonate
Toxics 2024, 12(4), 298; https://doi.org/10.3390/toxics12040298 - 17 Apr 2024
Abstract
As an alternative for perfluorooctane sulfonic acid (PFOS), sodium p-perfluorononyloxybenzene sulfonate (OBS) has been widely used in petroleum, fire-fighting materials, and other industries. In order to efficiently and economically remove OBS contaminations from water bodies, in this study, a ternary heterojunction was constructed
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As an alternative for perfluorooctane sulfonic acid (PFOS), sodium p-perfluorononyloxybenzene sulfonate (OBS) has been widely used in petroleum, fire-fighting materials, and other industries. In order to efficiently and economically remove OBS contaminations from water bodies, in this study, a ternary heterojunction was constructed by coupling BiOBr and BiOI@Bi5O7I for improving the redox capacity and carrier separation ability of the material and investigating the effect of the doping ratios of BiOBr and BiOI@ Bi5O7I on the performance of the catalysts. Furthermore, the effects on the degradation of OBS were also explored by adjusting different catalyst doping ratios, OBS concentrations, catalyst amounts, and pH values. It was observed that when the concentration of OBS was 50 mg/L, the amount of catalyst used was 0.5 g/L, and the pH was not changed. The application of BiOBr/BiOI@ Bi5O7I consisting of 25% BiOBr and 75% BiOI@ Bi5O7I showed excellent stability and adsorption degradation performance for OBS, and almost all of the OBS in the aqueous solution could be removed. The removal rate of OBS by BiOBr/BiOI@ Bi5O7I was more than 20% higher than that of OBS by BiOI@Bi5O7I and BiOBr when the OBS concentration was 100 mg/L. In addition, the reaction rate constants of BiOBr/BiOI@ Bi5O7I were 2.4 and 10.8 times higher than those of BiOI@ Bi5O7I and BiOBr, respectively. Therefore, the BiOBr/BiOI@ Bi5O7I ternary heterojunction can be a novel type of heterojunction for the efficient degradation of OBS in water bodies.
Full article
(This article belongs to the Special Issue Human Exposure to per- and Polyfluoroalkyl Substances (PFASs): Toxicity, Health Effects, and Mitigation)
Open AccessCommunication
Low Doses of Deoxynivalenol and Zearalenone Alone or in Combination with a Mycotoxin Binder Affect ABCB1 mRNA and ABCC2 mRNA Expression in the Intestines of Pigs
by
Nikolay Nikolov, Tsvetelina Petkova, Rumen Binev and Aneliya Milanova
Toxics 2024, 12(4), 297; https://doi.org/10.3390/toxics12040297 - 17 Apr 2024
Abstract
Mycotoxin binders, in combination with enzymes degrading some mycotoxins, contribute to feed detoxification. Their use reduces economic losses and the negative impacts of mycotoxins on animal health and productivity in farm animals. The aim of this study was to evaluate the efficacy of
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Mycotoxin binders, in combination with enzymes degrading some mycotoxins, contribute to feed detoxification. Their use reduces economic losses and the negative impacts of mycotoxins on animal health and productivity in farm animals. The aim of this study was to evaluate the efficacy of a mycotoxin detoxifier on the expression of the ATP-binding cassette efflux transporters ABCB1 mRNA and ABCC2 mRNA, which transport xenobiotics and thus have a barrier function, in the tissues of pigs exposed to low doses of deoxynivalenol (DON, 1 mg/kg feed) and zearalenone (ZEN, 0.4 mg/kg feed) for 37 days. The levels of expression were determined by an RT-PCR, and the effect of the mycotoxin detoxifier (Mycofix Plus3.E) was evaluated by a comparison of results between healthy pigs (n = 6), animals treated with DON and ZEN (n = 6), and a group that received both mycotoxins and the detoxifier (n = 6). A significant downregulation of ABCB1 mRNA and ABCC2 mRNA was observed in the jejunum (p < 0.05). A tendencies toward the downregulation of ABCB1 mRNA and ABCC2 mRNA were found in the ileum and duodenum, respectively. The mycotoxin detoxifier restored the expression of ABCB1 mRNA to the level found in healthy animals but did not restore that of ABCC2 mRNA to the level of healthy animals in the jejunum.
Full article
(This article belongs to the Special Issue Research on Veterinary Toxicology)
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Open AccessArticle
Decreased Ubiquitination and Acetylation of Histones 3 and 4 Are Associated with Obesity-Induced Disorders of Spermatogenesis in Mice
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Mahamadou Fofana, Zhenyang Li, Han Li, Wenqi Li, Lu Wu, Lu Lu and Qizhan Liu
Toxics 2024, 12(4), 296; https://doi.org/10.3390/toxics12040296 - 17 Apr 2024
Abstract
Background: Obesity, a chronic metabolic disorder, is related to cardiovascular diseases, diabetes, cancer, and reproductive disorders. The relationship between obesity and male infertility is now well recognized, but the mechanisms involved are unclear. We aimed to observe the effect of obesity on spermatogenesis
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Background: Obesity, a chronic metabolic disorder, is related to cardiovascular diseases, diabetes, cancer, and reproductive disorders. The relationship between obesity and male infertility is now well recognized, but the mechanisms involved are unclear. We aimed to observe the effect of obesity on spermatogenesis and to investigate the role of histone ubiquitination and acetylation modifications in obesity-induced spermatogenesis disorders. Methods: Thirty male C57BL/6J mice were randomly divided into two groups. The control group was fed with a general maintenance diet (12% fat), while a high-fat diet (HFD) group was fed with 40% fat for 10 weeks; then, they were mated with normal females. The fertility of male mice was calculated, testicular and sperm morphology were observed, and the expression levels of key genes and the levels of histone acetylation and ubiquitination modification during spermatogenesis were detected. Results: The number of sperm was decreased, as well as the sperm motility, while the number of sperm with malformations was increased. In the testes, the mRNA and protein expression levels of gonadotropin-regulated testicular RNA helicase (GRTH/DDX25), chromosome region maintenance-1 protein (CRM1), high-mobility group B2 (HMGB2), phosphoglycerate kinase 2 (PGK2), and testicular angiotensin-converting enzyme (tACE) were decreased. Furthermore, obesity led to a decrease in ubiquitinated H2A (ubH2A) and reduced levels of histone H3 acetylation K18 (H3AcK18) and histone H4 acetylation K5, K8, K12, and K16 (H4tetraAck), which disrupted protamine 1 (Prm1) deposition in testis tissue. Conclusion: These results suggest that low levels of histone ubiquitination and acetylation are linked with obesity-induced disorders during spermatogenesis, contributing to a better understanding of obesity-induced damage to male reproduction.
Full article
(This article belongs to the Section Reproductive and Developmental Toxicity)
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Open AccessArticle
Critical Environmental Injustice: A Case Study Approach to Understanding Disproportionate Exposure to Toxic Emissions
by
Clare E. B. Cannon
Toxics 2024, 12(4), 295; https://doi.org/10.3390/toxics12040295 - 17 Apr 2024
Abstract
Environmental justice research has focused on the distribution of environmental inequalities, such as proximity to landfills, across the U.S. and globally. Background: Public health research and environmental health research, specifically, have focused on toxic exposure—encompassing individuals or communities that are disproportionately exposed to
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Environmental justice research has focused on the distribution of environmental inequalities, such as proximity to landfills, across the U.S. and globally. Background: Public health research and environmental health research, specifically, have focused on toxic exposure—encompassing individuals or communities that are disproportionately exposed to contaminants that are harmful or potentially harmful to them. Yet, little research has applied critical environmental justice theory—characterized by the idea that marginalized communities need to be treated as indispensable rather than disposable—to the study of toxic exposure. To fill this gap, the current paper offers a case study approach applying critical environmental justice theory to the study of disproportionate and unequal exposure to toxic contaminants. Methods: This case study is of Kettleman City, a rural, unincorporated community in the heart of California’s Central Valley (USA). This community experiences the co-location of environmental hazards, including residing at the intersection of two major highways and hosting a class I hazardous-waste landfill, which is one of the few licensed to accept PCBs. PCBs are a contaminant that has been linked with several adverse health outcomes, including cancers and low birthweight. Residents may also experience poor air quality from proximity to the highways. Results: This case highlights the uneven distribution of pollution and environmental degradation that may be shouldered by the community, along with their experiences of adverse health and social impacts. This analysis reveals the importance of incorporating a critical environmental justice perspective to unpack experiences of not only disproportionate exposure but also disproportionate procedural and recognitional inequality. Conclusions: This research highlights the untapped potential of environmental justice to catalyze exposure science in challenging the unequal distribution of contaminants.
Full article
(This article belongs to the Special Issue Environmental Justice: Disproportionate Exposures to Toxic Contaminants)
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Open AccessReview
Bisphenol A Exposure Interferes with Reproductive Hormones and Decreases Sperm Counts: A Systematic Review and Meta-Analysis of Epidemiological Studies
by
Lei Lü, Yuan Liu, Yuhong Yang, Jinxing He, Lulu Luo, Shanbin Chen and Hanzhu Xing
Toxics 2024, 12(4), 294; https://doi.org/10.3390/toxics12040294 - 17 Apr 2024
Abstract
Bisphenol A (BPA), an acknowledged endocrine disrupter, is easily exposed to humans via food packaging and container. However, a consensus has not been reached on the extent to which BPA exposure affects the reproductive system. We therefore conducted this systematic review and meta-analysis
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Bisphenol A (BPA), an acknowledged endocrine disrupter, is easily exposed to humans via food packaging and container. However, a consensus has not been reached on the extent to which BPA exposure affects the reproductive system. We therefore conducted this systematic review and meta-analysis to elucidate the relationship between BPA exposure and male reproduction-related indicators. Up to October 2023, a comprehensive search was carried out in the PubMed, Embase, Cochrane and Web of Science, and 18 studies were ultimately included. β coefficients from multivariate linear regression analyses were pooled using a random effects model. The results showed that the urinary BPA concentration was negatively correlated with the sperm concentration (β coefficient = −0.03; 95% CI: −0.06 to −0.01; I2 = 0.0%, p = 0.003) and total sperm count (β coefficient = −0.05; 95% CI: −0.08 to −0.02; I2 = 0.0%, p < 0.001). In addition, BPA concentrations were associated with increased sex hormone-binding globulin (SHBG) levels, increased estradiol (E2) levels, and reduced biologically active androgen levels. However, the relationship between an increased risk of below-reference sperm quality and BPA exposure was not robust. This systematic review revealed that BPA exposure disrupts reproductive hormones, reduces sperm counts and may ultimately adversely affect male reproduction.
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(This article belongs to the Section Human Toxicology and Epidemiology)
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Open AccessArticle
Spatiotemporal Gradients of PAH Concentrations in Greek Cities and Associated Exposure Impacts
by
Irini Tsiodra, Kalliopi Tavernaraki, Georgios Grivas, Constantine Parinos, Kyriaki Papoutsidaki, Despina Paraskevopoulou, Eleni Liakakou, Alexandra Gogou, Aikaterini Bougiatioti, Evangelos Gerasopoulos, Maria Kanakidou and Nikolaos Mihalopoulos
Toxics 2024, 12(4), 293; https://doi.org/10.3390/toxics12040293 - 16 Apr 2024
Abstract
To study the spatiotemporal variability of particle-bound polycyclic aromatic hydrocarbons (PAHs) and assess their carcinogenic potential in six contrasting urban environments in Greece, a total of 305 filter samples were collected and analyzed. Sampling sites included a variety of urban background, traffic (Athens,
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To study the spatiotemporal variability of particle-bound polycyclic aromatic hydrocarbons (PAHs) and assess their carcinogenic potential in six contrasting urban environments in Greece, a total of 305 filter samples were collected and analyzed. Sampling sites included a variety of urban background, traffic (Athens, Ioannina and Heraklion), rural (Xanthi) and near-port locations (Piraeus and Volos). When considering the sum of 16 U.S. EPA priority PAHs, as well as that of the six EU-proposed members, average concentrations observed across locations during summer varied moderately (0.4–2.2 ng m−3) and independently of the population of each site, with the highest values observed in the areas of Piraeus and Volos that are affected by port and industrial activities. Winter levels were significantly higher and more spatially variable compared to summer, with the seasonal enhancement ranging from 7 times in Piraeus to 98 times in Ioannina, indicating the large impact of PAH emissions from residential wood burning. Regarding benzo(a)pyrene (BaP), an IARC Group 1 carcinogen and the only EU-regulated PAH, the winter/summer ratios were 24–33 in Athens, Volos, Heraklion and Xanthi; 60 in Piraeus; and 480 in Ioannina, which is afflicted by severe wood-burning pollution events. An excellent correlation was observed between organic carbon (OC) and benzo(a)pyrene (BaP) during the cold period at all urban sites (r2 > 0.8) with stable BaP/OC slopes (0.09–0.14 × 10−3), highlighting the potential use of OC as a proxy for the estimation of BaP in winter conditions. The identified spatiotemporal contrasts, which were explored for the first time for PAHs at such a scale in the Eastern Mediterranean, provide important insights into sources and controlling atmospheric conditions and reveal large deviations in exposure risks among cities that raise the issue of environmental injustice on a national level.
Full article
(This article belongs to the Special Issue Selected Papers from the 1st International Electronic Conference on Toxics)
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Open AccessArticle
PM2.5 Extracts Induce INFγ-Independent Activation of CIITA, MHCII, and Increases Inflammation in Human Bronchial Epithelium
by
Héctor Jirau-Colón and Braulio D. Jiménez-Vélez
Toxics 2024, 12(4), 292; https://doi.org/10.3390/toxics12040292 - 16 Apr 2024
Abstract
The capacity of particulate matter (PM) to enhance and stimulate the expression of pro-inflammatory mediators has been previously demonstrated in non-antigen-presenting cells (human bronchial epithelia). Nonetheless, many proposed mechanisms for this are extrapolated from known canonical molecular pathways. This work evaluates a possible
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The capacity of particulate matter (PM) to enhance and stimulate the expression of pro-inflammatory mediators has been previously demonstrated in non-antigen-presenting cells (human bronchial epithelia). Nonetheless, many proposed mechanisms for this are extrapolated from known canonical molecular pathways. This work evaluates a possible mechanism for inflammatory exacerbation after exposure to PM2.5 (from Puerto Rico) and CuSO4, using human bronchial epithelial cells (BEAS-2B) as a model. The induction of CIITA, MHCII genes, and various pro-inflammatory mediators was investigated. Among these, the phosphorylation of STAT1 Y701 was significantly induced after 4 h of PM2.5 exposure, concurrent with a slight increase in CIITA and HLA-DRα mRNA levels. INFγ mRNA levels remained low amidst exposure time, while IL-6 levels significantly increased at earlier times. IL-8 remained low, as expected from attenuation by IL-6 in the known INFγ-independent inflammation pathway. The effects of CuSO4 showed an increase in HLA-DRα expression after 8 h, an increase in STAT1 at 1 h, and RF1 at 8 h We hypothesize and show evidence that an inflammatory response due to PM2.5 extract exposure in human bronchial epithelia can be induced early via an alternate non-canonical pathway in the absence of INFγ.
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(This article belongs to the Special Issue Molecular Mechanisms of Toxicity from Air Pollutant Exposure)
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Improving Lead Phytoremediation Using Endophytic Bacteria Isolated from the Pioneer Plant Ageratina adenophora (Spreng.) from a Mining Area
by
Qiqian Li, Siyu Yao, Hua Wen, Wenqi Li, Ling Jin and Xiuxiang Huang
Toxics 2024, 12(4), 291; https://doi.org/10.3390/toxics12040291 - 16 Apr 2024
Abstract
This study aimed to isolate and characterise endophytic bacteria from the pioneer plant Ageratina adenophora in a mining area. Seven strains of metal-resistant endophytic bacteria that belong to five genera were isolated from the roots of A. adenophora. These strains exhibited various
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This study aimed to isolate and characterise endophytic bacteria from the pioneer plant Ageratina adenophora in a mining area. Seven strains of metal-resistant endophytic bacteria that belong to five genera were isolated from the roots of A. adenophora. These strains exhibited various plant growth-promoting (PGP) capabilities. Sphingomonas sp. ZYG-4, which exhibited the ability to secrete indoleacetic acid (IAA; 53.2 ± 8.3 mg·L−1), solubilize insoluble inorganic phosphates (Phosphate solubilization; 11.2 ± 2.9 mg·L−1), and regulate root ethylene levels (1-aminocyclopropane-1-carboxylic acid deaminase activity; 2.87 ± 0.19 µM α-KB·mg−1·h−1), had the highest PGP potential. Therefore, Sphingomonas sp. ZYG-4 was used in a pot experiment to study its effect on the biomass and Pb uptake of both host (Ageratina adenophora) and non-host (Dysphania ambrosioides) plants. Compared to the uninoculated control, Sphingomonas sp. ZYG-4 inoculation increased the biomass of shoots and roots by 59.4% and 144.4% for A. adenophora and by 56.2% and 57.1% for D. ambrosioides, respectively. In addition, Sphingomonas sp. ZYG-4 inoculation enhanced Pb accumulation in the shoot and root by 268.9% and 1187.3% for A. adenophora, and by 163.1% and 343.8% for D. ambrosioides, respectively, compared to plants without bacterial inoculation. Our research indicates that endophytic bacteria are promising candidates for enhancing plant growth and facilitating microbe-assisted phytoremediation in heavy metal-contaminated soil.
Full article
(This article belongs to the Special Issue Editorial Board Members’ Collection Series: Phytoremediation of Soil Polluted with Heavy Metals and Metalloids)
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Open AccessArticle
Concordance between In Vitro and In Vivo Relative Toxic Potencies of Diesel Exhaust Particles from Different Biodiesel Blends
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Subramanian Karthikeyan, Dalibor Breznan, Errol M. Thomson, Erica Blais, Renaud Vincent and Premkumari Kumarathasan
Toxics 2024, 12(4), 290; https://doi.org/10.3390/toxics12040290 - 16 Apr 2024
Abstract
Diesel exhaust particles (DEPs) contribute to air pollution exposure-related adverse health impacts. Here, we examined in vitro, and in vivo toxicities of DEPs from a Caterpillar C11 heavy-duty diesel engine emissions using ultra-low-sulfur diesel (ULSD) and biodiesel blends (20% v/v)
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Diesel exhaust particles (DEPs) contribute to air pollution exposure-related adverse health impacts. Here, we examined in vitro, and in vivo toxicities of DEPs from a Caterpillar C11 heavy-duty diesel engine emissions using ultra-low-sulfur diesel (ULSD) and biodiesel blends (20% v/v) of canola (B20C), soy (B20S), or tallow–waste fry oil (B20T) in ULSD. The in vitro effects of DEPs (DEPULSD, DEPB20C, DEPB20S, and DEPB20T) in exposed mouse monocyte/macrophage cells (J774A.1) were examined by analyzing the cellular cytotoxicity endpoints (CTB, LDH, and ATP) and secreted proteins. The in vivo effects were assessed in BALB/c mice (n = 6/group) exposed to DEPs (250 µg), carbon black (CB), or saline via intratracheal instillation 24 h post-exposure. Bronchoalveolar lavage fluid (BALF) cell counts, cytokines, lung/heart mRNA, and plasma markers were examined. In vitro cytotoxic potencies (e.g., ATP) and secreted TNF-α were positively correlated (p < 0.05) with in vivo inflammatory potency (BALF cytokines, lung/heart mRNA, and plasma markers). Overall, DEPULSD and DEPB20C appeared to be more potent compared to DEPB20S and DEPB20T. These findings suggested that biodiesel blend-derived DEP potencies can be influenced by biodiesel sources, and inflammatory process- was one of the potential underlying toxicity mechanisms. These observations were consistent across in vitro and in vivo exposures, and this work adds value to the health risk analysis of cleaner fuel alternatives.
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(This article belongs to the Section Air Pollution and Health)
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Open AccessArticle
Urinary Volatile Organic Compound Metabolites Are Associated with Reduced Lung Function in U.S. Children and Adolescents
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Angelico Mendy, Sara Burcham, Ashley L. Merianos, Tesfaye B. Mersha, Kimberly Yolton, Aimin Chen and E. Melinda Mahabee-Gittens
Toxics 2024, 12(4), 289; https://doi.org/10.3390/toxics12040289 - 16 Apr 2024
Abstract
(1) Background: Volatile organic compounds (VOCs) are indoor pollutants absorbed by inhalation. The association of several VOCs with lung function in children and adolescents is unknown. (2) Methods: We analyzed 505 participants, 6–17-year-olds from the 2011–2012 National Health and Nutrition Examination Survey. Multiple
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(1) Background: Volatile organic compounds (VOCs) are indoor pollutants absorbed by inhalation. The association of several VOCs with lung function in children and adolescents is unknown. (2) Methods: We analyzed 505 participants, 6–17-year-olds from the 2011–2012 National Health and Nutrition Examination Survey. Multiple linear regression models were fitted to estimate the associations of VOC metabolites with spirometry outcomes adjusting for covariates. (3) Results: Urinary metabolites of xylene, acrylamide, acrolein, 1,3-butadiene, cyanide, toluene, 1-bromopropane, acrylonitrile, propylene oxide, styrene, ethylbenzene, and crotonaldehyde were all detected in ≥64.5% of participants. Forced expiratory volume in 1 s (FEV1) % predicted was lower in participants with higher levels of metabolites of acrylamide (β: −7.95, 95% CI: −13.69, −2.21) and styrene (β: −6.33, 95% CI: −11.60, −1.07), whereas the FEV1 to forced vital capacity (FVC) ratio % was lower in children with higher propylene oxide metabolite levels (β: −2.05, 95% CI: −3.49, −0.61). FEV1 % predicted was lower with higher crotonaldehyde metabolite levels only in overweight/obese participants (β: −15.42, 95% CI: −26.76, −4.08) (Pinteraction < 0.001) and with higher 1-bromopropane metabolite levels only in those with serum cotinine > 1 ng/mL (β: −6.26, 95% CI: −9.69, −2.82) (Pinteraction < 0.001). (4) Conclusions: We found novel associations of metabolites for acrylamide, propylene oxide, styrene, 1-bromopropane and crotonaldehyde with lower lung function in children and adolescents.
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(This article belongs to the Section Human Toxicology and Epidemiology)
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Exposure to Molybdate Results in Metabolic Disorder: An Integrated Study of the Urine Elementome and Serum Metabolome in Mice
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Kun Zhou, Miaomiao Tang, Wei Zhang, Yanling Chen, Yusheng Guan, Rui Huang, Jiawei Duan, Zibo Liu, Xiaoming Ji, Yingtong Jiang, Yanhui Hu, Xiaoling Zhang, Jingjing Zhou and Minjian Chen
Toxics 2024, 12(4), 288; https://doi.org/10.3390/toxics12040288 - 14 Apr 2024
Abstract
The increasing use of molybdate has raised concerns about its potential toxicity in humans. However, the potential toxicity of molybdate under the current level of human exposure remains largely unknown. Endogenous metabolic alterations that are caused in humans by environmental exposure to pollutants
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The increasing use of molybdate has raised concerns about its potential toxicity in humans. However, the potential toxicity of molybdate under the current level of human exposure remains largely unknown. Endogenous metabolic alterations that are caused in humans by environmental exposure to pollutants are associated with the occurrence and progression of many diseases. This study exposed eight-week-old male C57 mice to sodium molybdate at doses relevant to humans (0.01 and 1 mg/kg/day) for eight weeks. Inductively coupled plasma mass spectrometry (ICP-MS) and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS) were utilized to assess changes in urine element levels and serum metabolites in mice, respectively. A total of 838 subjects from the NHANES 2017–2018 population database were also included in our study to verify the associations between molybdenum and cadmium found in mice. Analysis of the metabolome in mice revealed that four metabolites in blood serum exhibited significant changes, including 5-aminolevulinic acid, glycolic acid, l-acetylcarnitine, and 2,3-dihydroxypropyl octanoate. Analysis of the elementome revealed a significant increase in urine levels of cadmium after molybdate exposure in mice. Notably, molybdenum also showed a positive correlation with cadmium in humans from the NHANES database. Further analysis identified a positive correlation between cadmium and 2,3-dihydroxypropyl octanoate in mice. In conclusion, these findings suggest that molybdate exposure disrupted amino acid and lipid metabolism, which may be partially mediated by molybdate-altered cadmium levels. The integration of elementome and metabolome data provides sensitive information on molybdate-induced metabolic disorders and associated toxicities at levels relevant to human exposure.
Full article
(This article belongs to the Special Issue State-of-the-Art Environmental Chemicals Exposomics and Metabolomics)
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Dimethylcyclosiloxanes in Mobile Smart Terminal Devices: Concentrations, Distributions, Profiles, and Environmental Emissions
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Yuanna Xing, Yiming Ge, Shaoyou Lu, Tao Yang and Xianzhi Peng
Toxics 2024, 12(4), 287; https://doi.org/10.3390/toxics12040287 - 13 Apr 2024
Abstract
Dimethylcyclosiloxanes (DMCs) are utilized as vital monomers in the synthesis of organosilicon compounds, integral to the manufacture of mobile smart terminal devices. Toxicological studies have revealed potential endocrine-disrupting activity, reproductive toxicity, neurotoxicity, and other toxicities of the DMCs. This study investigated the concentrations
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Dimethylcyclosiloxanes (DMCs) are utilized as vital monomers in the synthesis of organosilicon compounds, integral to the manufacture of mobile smart terminal devices. Toxicological studies have revealed potential endocrine-disrupting activity, reproductive toxicity, neurotoxicity, and other toxicities of the DMCs. This study investigated the concentrations and composition profiles of seven DMCs, including hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and tetradecamethylcycloheptasiloxane (D7), hexadecamethylcyclooctasiloxane (D8), and octadecamethylcyclononasiloxane (D9) in three types of mobile smart terminal device components (silicone rubber, adhesive, and plastics). Environmental emissions of DMCs from silicone rubber materials were also estimated to improve the recognition of their potential fate within the environment. D5–D9 were widely present in silicone rubber and adhesives with detection rates ranging from 91–95.5% and 50–100%, respectively, while D3 and D4 were more frequently detected in plastics, both showing a detection rate of 61.1%. Silicone rubber had the highest total DMCs (∑7DMCs) and a concentration of 802.2 mg/kg, which were dominated by D7, D8, and D9. DMCs detected in adhesives were dominated by D4, D5, and D6. The estimated emission of ∑DMCs released into the environment in China from silicone rubber used in mobile smart terminal devices exceeds 5000 tons per year. Further studies are needed on the presence of DMCs in various commodities and environmental media to assess their ecological and human health impacts, as well as the toxicological effects of D7–D9 for the appropriate regulation of these chemicals.
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(This article belongs to the Special Issue Emerging Pollutants in the Environment: Occurrence, Fate, Risk Assessment and Degradation Methods)
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Distribution and Risk Assessment of Organophosphate Esters in Agricultural Soils and Plants in the Coastal Areas of South China
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Wangxing Luo, Siyu Yao, Jiahui Huang, Haochuan Wu, Haijun Zhou, Mingjiang Du, Ling Jin and Jianteng Sun
Toxics 2024, 12(4), 286; https://doi.org/10.3390/toxics12040286 - 12 Apr 2024
Abstract
Organophosphate esters (OPEs) are frequently used as flame retardants and plasticizers in various commercial products. While initially considered as substitutes for brominated flame retardants, they have faced restrictions in some countries due to their toxic effects on organisms. We collected 37 soil and
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Organophosphate esters (OPEs) are frequently used as flame retardants and plasticizers in various commercial products. While initially considered as substitutes for brominated flame retardants, they have faced restrictions in some countries due to their toxic effects on organisms. We collected 37 soil and crop samples in 20 cities along the coast of South China, and OPEs were detected in all of them. Meanwhile, we studied the contamination and potential human health risks of OPEs. In soil samples, the combined concentrations of eight OPEs varied between 74.7 and 410 ng/g, averaging at 255 ng/g. Meanwhile, in plant samples, the collective concentrations of eight OPEs ranged from 202 to 751 ng/g, with an average concentration of 381 ng/g. TDCIPP, TCPP, TCEP, and ToCP were the main OPE compounds in both plant and soil samples. Within the study area, the contaminants showed different spatial distributions. Notably, higher OPEs were found in coastal agricultural soils in Guangdong Province and crops in the Guangxi Zhuang Autonomous Region. The results of an ecological risk assessment show that the farmland soil along the southern coast of China is at high or medium ecological risk. The average non-carcinogenic risk and the carcinogenic risk of OPEs in soil through ingestion and dermal exposure routes are within acceptable levels. Meanwhile, this study found that the dietary intake of OPEs through food is relatively low, but twice as high as other studies, requiring serious attention. The research findings suggest that the human risk assessment indicates potential adverse effects on human health due to OPEs in the soil–plant system along the coast of South China. This study provides a crucial foundation for managing safety risks in agricultural operations involving OPEs.
Full article
(This article belongs to the Special Issue Distribution, Metabolism, and Toxicity Exposure of Emerging Toxics)
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Rat Hepatocytes Protect against Lead–Cadmium-Triggered Apoptosis Based on Autophagy Activation
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Junshu Xue, Huimao Liu, Tianyi Yin, Xun Zhou, Xu Song, Yuanfeng Zou, Lixia Li, Renyong Jia, Yuping Fu, Xinghong Zhao and Zhongqiong Yin
Toxics 2024, 12(4), 285; https://doi.org/10.3390/toxics12040285 - 12 Apr 2024
Abstract
Lead and cadmium are foodborne contaminants that threaten human and animal health. It is well known that lead and cadmium produce hepatotoxicity; however, defense mechanisms against the co-toxic effects of lead and cadmium remain unknown. We investigated the mechanism of autophagy (defense mechanism)
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Lead and cadmium are foodborne contaminants that threaten human and animal health. It is well known that lead and cadmium produce hepatotoxicity; however, defense mechanisms against the co-toxic effects of lead and cadmium remain unknown. We investigated the mechanism of autophagy (defense mechanism) against the co-induced toxicity of lead and cadmium in rat hepatocytes (BRL-3A cells). Cultured rat liver BRL-3A cell lines were co-cultured with 10, 20, 40 μM lead and 2.5, 5, 10 μM cadmium alone and in co-culture for 12 h and exposed to 5 mM 3-Methyladenine (3-MA), 10 μM rapamycin (Rapa), and 50 nM Beclin1 siRNA to induce cellular autophagy. Our results show that treatment of BRL-3A cells with lead and cadmium significantly decreased the cell viability, increased intracellular reactive oxygen species levels, decreased mitochondrial membrane potential levels, and induced apoptosis, which are factors leading to liver injury, and cell damage was exacerbated by co-exposure to lead–cadmium. In addition, the results showed that lead and cadmium co-treatment induced autophagy. We further observed that the suppression of autophagy with 3-MA or Beclin1 siRNA promoted lead–cadmium-induced apoptosis, whereas enhancement of autophagy with Rapa suppressed lead–cadmium-induced apoptosis. These results demonstrated that co-treatment with lead and cadmium induces apoptosis in BRL-3A cells. Interestingly, the activation of autophagy provides cells with a self-protective mechanism against induced apoptosis. This study provides insights into the role of autophagy in lead–cadmium-induced apoptosis, which may be beneficial for the treatment of lead–cadmium-induced liver injury.
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(This article belongs to the Special Issue Toxicology Research of Foodborne Contaminants)
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Glycyrrhiza Extract and Curcumin Alleviates the Toxicity of Cadmium via Improving the Antioxidant and Immune Functions of Black Goats
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Yang Ran, Xiaoyun Shen and Yuanfeng Li
Toxics 2024, 12(4), 284; https://doi.org/10.3390/toxics12040284 - 12 Apr 2024
Abstract
To investigate the mitigative effects of glycyrrhiza extract (GE) and curcumin (CUR) on the antioxidant and immune functions of the Guizhou black goat exposed to cadmium (Cd), 50 healthy Guizhou black goats (11.08 ± 0.22 kg, male, six months old) were used in
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To investigate the mitigative effects of glycyrrhiza extract (GE) and curcumin (CUR) on the antioxidant and immune functions of the Guizhou black goat exposed to cadmium (Cd), 50 healthy Guizhou black goats (11.08 ± 0.22 kg, male, six months old) were used in a 60-day trial and were randomly assigned to five groups with 10 replicates per group, one goat per replicate. All goats were fed a basal diet, with drinking water and additives varying slightly between groups. Control group: tap water (0.56 μg·L−1 Cd); Cd group: drinking water containing Cd (20 mg Cd·kg−1·body weight, CdCl2·2.5H2O); GE group: drinking water containing Cd, at days 31 to 60, the basic diet had added 500 mg·kg−1 GE; CUR group: drinking water containing Cd, at days 31 to 60, the basic diet had added 500 mg·kg−1 CUR; combined group: drinking water containing Cd, at days 31 to 60, the basic diet had added 500 mg·kg−1 GE and CUR. Compared with the Cd group, GE and CUR significantly increased the levels of hemoglobin and red blood cell count in the blood, and the activities of serum antioxidant enzyme activity and immune function in the Guizhou black goat (p < 0.05). The treatment effect in the combined group was better than that in the GE and CUR groups. The results showed that GE and CUR improved the antioxidant and immune functions of the serum and livers of the Guizhou black goat and alleviated the toxicity damage of Cd contamination. This research has positive implications for both livestock management and human health.
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(This article belongs to the Section Ecotoxicology)
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Open AccessArticle
Effective Activation of Peroxymonosulfate by Oxygen Vacancy Induced Musa Basjoo Biochar to Degrade Sulfamethoxazole: Efficiency and Mechanism
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Shuqi Li, Jian Yang, Kaiwen Zheng, Shilong He, Zhigang Liu, Shuang Song and Tao Zeng
Toxics 2024, 12(4), 283; https://doi.org/10.3390/toxics12040283 - 12 Apr 2024
Abstract
Biochar materials have garnered attention as potential catalysts for peroxymonosulfate (PMS) activation due to their cost-effectiveness, notable specific surface area, and advantageous structural properties. In this study, a suite of plantain-derived biochar (MBB-400, MBB-600, and MBB-800), possessing a well-defined pore structure and a
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Biochar materials have garnered attention as potential catalysts for peroxymonosulfate (PMS) activation due to their cost-effectiveness, notable specific surface area, and advantageous structural properties. In this study, a suite of plantain-derived biochar (MBB-400, MBB-600, and MBB-800), possessing a well-defined pore structure and a substantial number of uniformly distributed active sites (oxygen vacancy, OVs), was synthesized through a facile calcination process at varying temperatures (400, 600, and 800 °C). These materials were designed for the activation of PMS in the degradation of sulfamethoxazole (SMX). Experimental investigations revealed that OVs not only functioned as enriched sites for pollutants, enhancing the opportunities for free radicals (•OH/SO4•−) and surface-bound radicals (SBRs) to attack pollutants, but also served as channels for intramolecular charge transfer leaps. This role contributed to a reduction in interfacial charge transfer resistance, expediting electron transfer rates with PMS, thereby accelerating the decomposition of pollutants. Capitalizing on these merits, the MBB-800/PMS system displayed a 61-fold enhancement in the conversion rate for SMX degradation compared to inactivated MBB/PMS system. Furthermore, the MBB-800 exhibited less cytotoxicity towards rat pheochromocytoma (PC12) cells. Hence, the straightforward calcination synthesis of MBB-800 emerges as a promising biochar catalyst with vast potential for sustainable and efficient wastewater treatment and environmental remediation.
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(This article belongs to the Section Toxicity Reduction and Environmental Remediation)
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Neurotoxicity of Combined Exposure to the Heavy Metals (Pb and As) in Zebrafish (Danio rerio)
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Ming Liu, Ping Deng, Guangyu Li, Haoling Liu, Junli Zuo, Wenwen Cui, Huixian Zhang, Xin Chen, Jingjing Yao, Xitian Peng, Lijun Peng, Jiao Liu, Wenting Zheng, Wei Yan and Ning Luan
Toxics 2024, 12(4), 282; https://doi.org/10.3390/toxics12040282 - 11 Apr 2024
Abstract
Lead (Pb) and arsenic (As) are commonly occurring heavy metals in the environment and produce detrimental impacts on the central nervous system. Although they have both been indicated to exhibit neurotoxic properties, it is not known if they have joint effects, and their
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Lead (Pb) and arsenic (As) are commonly occurring heavy metals in the environment and produce detrimental impacts on the central nervous system. Although they have both been indicated to exhibit neurotoxic properties, it is not known if they have joint effects, and their mechanisms of action are likewise unknown. In this study, zebrafish were exposed to different concentrations of Pb (40 μg/L, 4 mg/L), As (32 μg/L, 3.2 mg/L) and their combinations (40 μg/L + 32 μg/L, 4 mg/L + 3.2 mg/L) for 30 days. The histopathological analyses showed significant brain damage characterized by glial scar formation and ventricular enlargement in all exposed groups. In addition, either Pb or As staining inhibited the swimming speed of zebrafish, which was enhanced by their high concentrations in a mixture. To elucidate the underlying mechanisms, we examined changes in acetylcholinesterase (AChE) activity, neurotransmitter (dopamine, 5-hydroxytryptamine) levels, HPI axis-related hormone (cortisol and epinephrine) contents and neurodevelopment-related gene expression in zebrafish brain. The observations suggest that combined exposure to Pb and As can cause abnormalities in swimming behavior and ultimately exacerbate neurotoxicity in zebrafish by interfering with the cholinergic system, dopamine and 5-hydroxytryptamine signaling, HPI axis function as well as neuronal development. This study provides an important theoretical basis for the mixed exposure of heavy metals and their toxicity to aquatic organisms.
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(This article belongs to the Section Metals and Radioactive Substances)
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Thyroid Hormone Receptor Agonistic and Antagonistic Activity of Newly Synthesized Dihydroxylated Polybrominated Diphenyl Ethers: An In Vitro and In Silico Coactivator Recruitment Study
by
Mengtao Zhang, Jianghong Shi, Bin Li, Hui Ge, Huanyu Tao, Jiawei Zhang, Xiaoyan Li and Zongwei Cai
Toxics 2024, 12(4), 281; https://doi.org/10.3390/toxics12040281 - 11 Apr 2024
Abstract
Dihydroxylated polybrominated diphenyl ethers (DiOH-PBDEs) could be the metabolites of PBDEs of some organisms or the natural products of certain marine bacteria and algae. OH-PBDEs may demonstrate binding affinity to thyroid hormone receptors (TRs) and can disrupt the functioning of the systems modulated
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Dihydroxylated polybrominated diphenyl ethers (DiOH-PBDEs) could be the metabolites of PBDEs of some organisms or the natural products of certain marine bacteria and algae. OH-PBDEs may demonstrate binding affinity to thyroid hormone receptors (TRs) and can disrupt the functioning of the systems modulated by TRs. However, the thyroid hormone disruption mechanism of diOH-PBDEs remains elusive due to the absence of diOH-PBDEs standards. This investigation explores the potential disruptive effects of OH/diOH-PBDEs on thyroid hormones via competitive binding and coactivator recruitment with TRα and TRβ. At levels of 5000 nM and 25,000 nM, 6-OH-BDE-47 demonstrated significant recruitment of steroid receptor coactivator (SRC), whereas none of the diOH-PBDEs exhibited SRC recruitment within the range of 0.32–25,000 nM. AutoDock CrankPep (ADCP) simulations suggest that the conformation of SRC and TR–ligand complexes, particularly their interaction with Helix 12, rather than binding affinity, plays a pivotal role in ligand agonistic activity. 6,6′-diOH-BDE-47 displayed antagonistic activity towards both TRα and TRβ, while the antagonism of 3,5-diOH-BDE-100 for TRα and TRβ was concentration-dependent. 3,5-diOH-BDE-17 and 3,5-diOH-BDE-51 exhibited no discernible agonistic or antagonistic activities. Molecular docking analysis revealed that the binding energy of 3,3′,5-triiodo-L-thyronine (T3) surpassed that of OH/diOH-PBDEs. 3,5-diOH-BDE-100 exhibited the highest binding energy, whereas 6,6′-diOH-BDE-47 displayed the lowest. These findings suggest that the structural determinants influencing the agonistic and antagonistic activities of halogen phenols may be more intricate than previously proposed, involving factors beyond high-brominated PBDEs or hydroxyl group and bromine substitutions. It is likely that the agonistic or antagonistic propensities of OH/diOH-PBDEs are instigated by protein conformational changes rather than considerations of binding energy.
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(This article belongs to the Section Emerging Contaminants)
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Influence of Phosphate on Arsenic Adsorption Behavior of Si-Fe-Mg Mixed Hydrous Oxide
by
Marjjuk Ahmed and Tomoyuki Kuwabara
Toxics 2024, 12(4), 280; https://doi.org/10.3390/toxics12040280 - 11 Apr 2024
Abstract
The arsenic adsorption performance of silicon (Si), iron (Fe), and magnesium (Mg) mixed hydrous oxide containing a Si: Fe: Mg metal composition ratio of 0.05:0.9:0.05 (SFM05905) was investigated. SFM05905 was synthesized by the co-precipitation method. Batch experiments on arsenic adsorption were conducted at
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The arsenic adsorption performance of silicon (Si), iron (Fe), and magnesium (Mg) mixed hydrous oxide containing a Si: Fe: Mg metal composition ratio of 0.05:0.9:0.05 (SFM05905) was investigated. SFM05905 was synthesized by the co-precipitation method. Batch experiments on arsenic adsorption were conducted at various temperatures and concentrations. Adsorption isotherms models were represented by a linearized equations and were insensitive to temperature change. The anion selectivity of SFM05905 at single component was high for arsenite (III), arsenate (V), and phosphate (PO4), indicating that PO4 inhibits arsenic adsorption. The adsorption amount of As (III), As (V), and PO4 were compared using a column packed with granular SFM05905, and an aqueous solution was passed by a combination of several anions that are single, binary, and ternary adsorbate systems. As (III) had the highest adsorption amount; however, As (III) and PO4 were affected by each other under the ternary mixing condition. Although the adsorption amount of As (V) was smaller than that of As (III), it was not affected by other adsorbates in the column experiments. Finally, although the adsorption of both arsenic continued, the adsorbed PO4 gradually desorbed.
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(This article belongs to the Special Issue Techniques and Methods for Toxic Agent Analysis and Removal)
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Wide Riparian Zones Inhibited Trace Element Loss in Mining Wastelands by Reducing Surface Runoff and Trace Elements in Sediment
by
Jiangdi Deng, Zuran Li, Bo Li, Cui Xu, Lei Wang and Yuan Li
Toxics 2024, 12(4), 279; https://doi.org/10.3390/toxics12040279 - 11 Apr 2024
Abstract
The diffusion of trace elements in mining wastelands has attracted widespread attention in recent years. Vegetation restoration is an effective measure for controlling the surface migration of trace elements. However, there is no field evidence of the effective riparian zone width in mining
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The diffusion of trace elements in mining wastelands has attracted widespread attention in recent years. Vegetation restoration is an effective measure for controlling the surface migration of trace elements. However, there is no field evidence of the effective riparian zone width in mining wastelands. Three widths (5 m, 7.5 m, and 10 m) of Rhododendron simsii/Lolium perenne L. riparian zones were constructed in lead–zinc mining wastelands to investigate the loss of soil, cadmium (Cd), copper (Cu), arsenic (As), lead (Pb), and zinc (Zn). Asbestos tiles were used to cut off connections between adjacent plots to avoid hydrological interference. Plastic pipes and containers were used to collect runoff water. Results showed that more than 90% of trace elements were lost in sediment during low coverage and heavy rainfall periods. Compared with the 5 m riparian zone, the total trace element loss was reduced by 69–85% during the whole observation period in the 10 m riparian zone and by 86–99% during heavy rain periods in the 10 m riparian zone, which was due to reduction in runoff and concentrations of sediment and trace elements in the 10 m riparian zone. Indirect negative effects of riparian zone width on trace element loss through runoff and sediment concentration were found. These results indicated that the wide riparian zone promoted water infiltration, filtered soil particles, and reduced soil erosion and trace element loss. Riparian zones can be used as environmental management measures after mining areas are closed to reduce the spread of environmental risks in mining wastelands, although the long-term effects remain to be determined.
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(This article belongs to the Section Metals and Radioactive Substances)
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