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Toxics, Volume 11, Issue 3 (March 2023) – 93 articles

Cover Story (view full-size image): Photoaging is a fairly common and typical behavior of microplastics (MPs) in the environment, which may lead to significant changes in their particle properties and induce ecotoxicological effects. This study aimed to explore the physiological toxicity, nutrient inhibition, oxidative stress, and antioxidant regulation mechanisms of different types of pristine and photoaged MPs on Pisum sativum L. seedlings. Notably, the production of superoxide anion radicals (•O2) and hydroxyl radicals (•OH) through the photoaging of MPs exacerbated oxidative stress and reactive oxygen species (ROS) formation in roots. Overall, this study emphasized that the photoaging behavior of MPs is a critical factor in further exploring the environmental risk and toxicity mechanism of plastics. View this paper
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14 pages, 1517 KiB  
Article
Future Health Risk Assessment of Exposure to PM2.5 in Different Age Groups of Children in Northern Thailand
by Teerachai Amnuaylojaroen and Nichapa Parasin
Toxics 2023, 11(3), 291; https://doi.org/10.3390/toxics11030291 - 22 Mar 2023
Cited by 11 | Viewed by 2454
Abstract
Particulate matter with a diameter less than 2.5 (PM2.5) is one of the major threats posed by air pollution to human health. It penetrates the respiratory system, particularly the lungs. In northern Thailand, the PM2.5 concentrations have significantly increased in [...] Read more.
Particulate matter with a diameter less than 2.5 (PM2.5) is one of the major threats posed by air pollution to human health. It penetrates the respiratory system, particularly the lungs. In northern Thailand, the PM2.5 concentrations have significantly increased in the past decade, becoming a major concern for the health of children. This study aimed to assess the health risk of PM2.5 in different age groups of children in northern Thailand between 2020 and 2029. Based on the PM2.5 data from the simulation of the Nested Regional Climate Model with Chemistry (NRCM-Chem), the hazard quotient (HQ) was used to estimate the possible risk from PM2.5 exposure in children. In general, all age groups of children in northern Thailand will tend to experience the threat of PM2.5 in the future. In the context of age-related development periods, infants are at a higher risk than other groups (toddlers, young children, school age and adolescents), but adolescents also have a lower risk of exposure to PM2.5, albeit maintaining a high HQ value (>1). Moreover, the analysis of risk assessment in different age groups of children revealed that PM2.5 exposure might indeed affect adolescent risk differently depending on gender, with males generally at a heightened risk than females in adolescence. Full article
(This article belongs to the Special Issue Ambient Air Pollution Exposure and Human Health)
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16 pages, 1593 KiB  
Article
Electronic Cigarette Usage Patterns and Perceptions in Adult Australians
by Alexander N. Larcombe, Emily K. Chivers, Rachel R. Huxley, Arthur (Bill) W. Musk, Peter J. Franklin and Benjamin J. Mullins
Toxics 2023, 11(3), 290; https://doi.org/10.3390/toxics11030290 - 21 Mar 2023
Cited by 1 | Viewed by 1876
Abstract
Despite their increasing popularity, and Australia’s unique regulatory environment, how and why Australian adults use e-cigarettes and their perceptions of their safety, efficacy and regulation have not been extensively reported before. In this study, we screened 2217 adult Australians with the aim of [...] Read more.
Despite their increasing popularity, and Australia’s unique regulatory environment, how and why Australian adults use e-cigarettes and their perceptions of their safety, efficacy and regulation have not been extensively reported before. In this study, we screened 2217 adult Australians with the aim of assessing these questions in a sample of current or former e-cigarette users. A total of 505 out of 2217 respondents were current or former e-cigarette users, with only these respondents completing the full survey. Key findings of this survey included the high proportion of respondents who indicated they were currently using e-cigarettes (307 out of 2217 = 13.8%), and the high proportion of current e-cigarette users that were also smokers (74.6%). The majority of respondents used e-liquids containing nicotine (70.3%), despite it being illegal in Australia without a prescription, and the majority bought their devices and liquids in Australia (65.7%). Respondents reported using e-cigarettes in a variety of places, including inside the home, inside public places (where it is illegal to smoke tobacco cigarettes), and around other people—which has implications for second and third hand exposures. A significant proportion of current e-cigarette users (30.6%) thought that e-cigarettes were completely safe to use long-term, although in general, there was a large amount of uncertainty/ambivalence with respect to perceptions of e-cigarette safety and efficacy as smoking cessation tools. This study shows that e-cigarette use is common in Australia, and that appropriate dissemination of unbiased research findings on their safety and efficacy in smoking cessation is urgently required. Full article
(This article belongs to the Section Human Toxicology and Epidemiology)
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13 pages, 645 KiB  
Article
Preliminary Study on an Alternative Test Method with MCTT HCETM for Ocular Irritation Test of Ophthalmic Medical Devices
by Yang-Jee Kim, Dong-Hyuk Seo, Il-Soo Kim, Mi-Sook Jung, Jin-Young Bae, Moon-Yong Song, Kyung-Seuk Song and Jin-Sik Kim
Toxics 2023, 11(3), 289; https://doi.org/10.3390/toxics11030289 - 21 Mar 2023
Viewed by 1629
Abstract
The sustained growth of the market for ophthalmic medical devices has increased the demand for alternatives to animal testing for the evaluation of eye irritation. The International Organization for Standardization has acknowledged the need to develop novel in vitro tests to replace animal [...] Read more.
The sustained growth of the market for ophthalmic medical devices has increased the demand for alternatives to animal testing for the evaluation of eye irritation. The International Organization for Standardization has acknowledged the need to develop novel in vitro tests to replace animal testing. Here, we evaluated the applicability of an alternative method based on a human corneal model to test the safety of ophthalmic medical devices. 2-Hydroxyethyl methacrylate (HEMA) and Polymethyl methacrylate (PMMA), which are used to fabricate contact lenses, were used as base materials. These materials were blended with eye irritant and non-irritant chemicals specified in the OECD Test Guideline (TG) 492 and Globally Harmonized System (GHS) classification. Then, three GLP-certified laboratories performed three replicates using the developed method using 3D reconstructed human cornea epithelium, MCTT HCETM. OECD TG 492 describes the procedure used to evaluate the eye hazard potential of the test chemical based on its ability to induce cytotoxicity in a reconstructed human cornea-like epithelium (RhCE) tissue. Results: The within-laboratory reproducibility (WLR) and between-laboratory reproducibility (BLR) were both 100%. When a polar extraction solvent was used, the sensitivity, specificity, and accuracy were all 100% in each laboratory. When a non-polar extraction solvent was used, the sensitivity was 80%, the specificity was 100%, and the accuracy was 90%. The proposed method exhibited excellent reproducibility and predictive capacity within and between laboratories. Therefore, the proposed method using the MCTT HCETM model could be used to evaluate eye irritation caused by ophthalmic medical devices. Full article
(This article belongs to the Section Exposome Analysis and Risk Assessment)
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11 pages, 2103 KiB  
Article
Effect of Soil Washing with an Amino-Acid-Derived Ionic Liquid on the Properties of Cd-Contaminated Paddy Soil
by Yun Deng, Sheng Wang, Ian Beadham, Xin Gao, Mengmeng Ji, Guang Wang, Changbo Zhang and Wenquan Ruan
Toxics 2023, 11(3), 288; https://doi.org/10.3390/toxics11030288 - 20 Mar 2023
Cited by 1 | Viewed by 1239
Abstract
To reduce contamination levels in Cd-contaminated paddy soil while retaining soil characteristics, we have studied the Cd-removing ability of 15 different amino acid-based ionic liquids, which are considered to be green solvents, as soil washing agents and their impact on soil. The results [...] Read more.
To reduce contamination levels in Cd-contaminated paddy soil while retaining soil characteristics, we have studied the Cd-removing ability of 15 different amino acid-based ionic liquids, which are considered to be green solvents, as soil washing agents and their impact on soil. The results indicated that the glycine hydrochloride ([Gly][Cl]) removed the most Cd, and under optimized conditions could remove 82.2% of the total Cd. Encouragingly, the morphology of the soil had not been significantly changed by the washing process. After the soil was rinsed twice with water and the pH was adjusted to 6.2 by adding Ca(OH)2, the germination index of the rice increased by 7.5%. The growth of the rice was also stimulated, with lengths and weights of the rice plants increasing by 56% and 32%, respectively, after two weeks. These experiments demonstrate that amino-acid-derived ionic liquids can be promising soil-washing agents of Cd-contaminated paddy soil. Full article
(This article belongs to the Special Issue Safety Utilization and Remediation of Heavy Metal Polluted Farmland)
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38 pages, 9065 KiB  
Article
Psychological Health and Drugs: Data-Driven Discovery of Causes, Treatments, Effects, and Abuses
by Sarah Alswedani, Rashid Mehmood, Iyad Katib and Saleh M. Altowaijri
Toxics 2023, 11(3), 287; https://doi.org/10.3390/toxics11030287 - 20 Mar 2023
Cited by 4 | Viewed by 3424
Abstract
Mental health issues can have significant impacts on individuals and communities and hence on social sustainability. There are several challenges facing mental health treatment; however, more important is to remove the root causes of mental illnesses because doing so can help prevent mental [...] Read more.
Mental health issues can have significant impacts on individuals and communities and hence on social sustainability. There are several challenges facing mental health treatment; however, more important is to remove the root causes of mental illnesses because doing so can help prevent mental health problems from occurring or recurring. This requires a holistic approach to understanding mental health issues that are missing from the existing research. Mental health should be understood in the context of social and environmental factors. More research and awareness are needed, as well as interventions to address root causes. The effectiveness and risks of medications should also be studied. This paper proposes a big data and machine learning-based approach for the automatic discovery of parameters related to mental health from Twitter data. The parameters are discovered from three different perspectives: Drugs and Treatments, Causes and Effects, and Drug Abuse. We used Twitter to gather 1,048,575 tweets in Arabic about psychological health in Saudi Arabia. We built a big data machine learning software tool for this work. A total of 52 parameters were discovered for all three perspectives. We defined six macro-parameters (Diseases and Disorders, Individual Factors, Social and Economic Factors, Treatment Options, Treatment Limitations, and Drug Abuse) to aggregate related parameters. We provide a comprehensive account of mental health, causes, medicines and treatments, mental health and drug effects, and drug abuse, as seen on Twitter, discussed by the public and health professionals. Moreover, we identify their associations with different drugs. The work will open new directions for a social media-based identification of drug use and abuse for mental health, as well as other micro and macro factors related to mental health. The methodology can be extended to other diseases and provides a potential for discovering evidence for forensics toxicology from social and digital media. Full article
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17 pages, 4261 KiB  
Article
Detection of Heavy Metals, Their Distribution in Tilapia spp., and Health Risks Assessment
by Leonel C. Mendoza, Ronnel C. Nolos, Oliver B. Villaflores, Enya Marie D. Apostol and Delia B. Senoro
Toxics 2023, 11(3), 286; https://doi.org/10.3390/toxics11030286 - 20 Mar 2023
Cited by 6 | Viewed by 5893
Abstract
Concentrations of heavy metals (HMs) were assessed in Tilapia spp. from selected communities in Calapan City, Philippines. Eleven (11) inland farmed tilapia samples were collected and analyzed for HMs concentration using X-ray fluorescence (XRF). The 11 fish samples were cut into seven pieces, [...] Read more.
Concentrations of heavy metals (HMs) were assessed in Tilapia spp. from selected communities in Calapan City, Philippines. Eleven (11) inland farmed tilapia samples were collected and analyzed for HMs concentration using X-ray fluorescence (XRF). The 11 fish samples were cut into seven pieces, according to the fish body parts, constituting a total of 77 samples. These fish samples were then labeled as bone, fins, head, meat, skin, and viscera. Results showed that the mean concentration of Cd in all parts of tilapia exceeded the Food and Agriculture Organization/World Health Organization (FAO/WHO) limits. The highest concentration was recorded in the fins, which was sevenfold higher than the limit. The trend of the mean concentration of Cd in different parts of tilapia was fins > viscera > skin > tail > head > meat > bone. The target hazard quotient (THQ) recorded a value less than 1. This means that the population exposed to tilapia, within the area where fish samples originated, were not at risk to non-carcinogens. The concentrations of Cu, Pb, Mn, Hg, and Zn in different parts, particularly in skin, fins, and viscera, also exceeded the FAO/WHO limits. The calculated cancer risk (CR) in consuming the fish skin, meat, fins, bone, viscera, and head was higher than the USEPA limit. This indicated a possible carcinogenic risk when consumed regularly. Most of the correlations observed between HMs in various parts of the tilapia had positive (direct) relationships, which were attributed to the HM toxicity target organ characteristics. Results of the principal component analysis (PCA) showed that most of the dominating HMs recorded in tilapia were attributable to anthropogenic activities and natural weathering within the watershed of agricultural areas. The agriculture area comprises about 86.83% of the overall land area of Calapan City. The identified carcinogenic risks were associated with Cd. Therefore, regular monitoring of HMs in inland fishes, their habitat, and surface water quality shall be carried out. This information is useful in creating strategies in metals concentration monitoring, health risks reduction program, and relevant guidelines that would reduce the accumulation of HM in fish. Full article
(This article belongs to the Special Issue Environmental and Health Effects of Heavy Metal)
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19 pages, 5061 KiB  
Article
Ecotoxicity of o-Chlorobenzylidene Malononitrile (CBM) and Toxicological Risk Assessment for SCLP Biological Cultures (Saccharomyces sp., Chlorella sp., Lactobacillus sp., Paramecium sp.)
by Viorel Gheorghe, Catalina Gabriela Gheorghe, Andreea Bondarev and Raluca Somoghi
Toxics 2023, 11(3), 285; https://doi.org/10.3390/toxics11030285 - 20 Mar 2023
Cited by 1 | Viewed by 2053
Abstract
Toxic substances used as chemical weapons present a number of particularities that affect the surrounding environment, having a wide range of action by disrupting the ecological balance: they may infect soil or air, or form aerosols through smoke or toxic fog. Such substances [...] Read more.
Toxic substances used as chemical weapons present a number of particularities that affect the surrounding environment, having a wide range of action by disrupting the ecological balance: they may infect soil or air, or form aerosols through smoke or toxic fog. Such substances can have a long duration of action, from minutes to weeks, which is why they are used in military attacks. This study evaluated the toxicological character of o-chlorobenzyliden malonitrile (CBM) in order to study the toxicity limit of this substance using microbiological cultures of Saccharomyces sp., Chlorella sp., Lactobacillus sp. and Paramecium sp., which were used to determine their rate of growth in the presence of different concentrations of o-chlorobenzyliden malonitrile and their ability to respond to this toxic stimulus. Full article
(This article belongs to the Special Issue Environmental Pollution and Related Aquatic Ecotoxicity)
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11 pages, 1143 KiB  
Article
Kinetics of Excretion of the Perfluoroalkyl Surfactant cC6O4 in Humans
by Silvia Fustinoni, Rosa Mercadante, Giorgia Lainati, Simone Cafagna and Dario Consonni
Toxics 2023, 11(3), 284; https://doi.org/10.3390/toxics11030284 - 20 Mar 2023
Cited by 2 | Viewed by 1737
Abstract
cC6O4 is a new-generation perfluoroalkyl surfactant used in the chemical industry for the synthesis of perfluoroalkyl polymers. It was introduced as a less biopersistent substitute of traditional perfluoroalkyl surfactants such as PFOA, but its kinetics in humans was never investigated. [...] Read more.
cC6O4 is a new-generation perfluoroalkyl surfactant used in the chemical industry for the synthesis of perfluoroalkyl polymers. It was introduced as a less biopersistent substitute of traditional perfluoroalkyl surfactants such as PFOA, but its kinetics in humans was never investigated. This work is aimed to investigate the kinetics of elimination of cC6O4 in exposed workers. Eighteen male individuals occupationally exposed to cC6O4 in the production of fluoropolymers volunteered for the study. Blood and urine samples were collected from the end of a work-shift for the following 5 days off work. Serum and urinary cC6O4 were measured by LC-MS/MS. Seventy-two samples with serum cC6O4 ranging from 0.38 to 11.29 µg/L were obtained; mean levels were 3.07, 2.82, 2.67 and 2.01 µg/L at times 0, 18, 42 and 114 h. Two hundred and fifty-four urine samples with cC6O4 ranging from 0.19 to 5.92 µg/L were obtained. A random-intercept multiple regression model was applied to serum data and a half-life of 184 (95% CI 162–213) h for a first-order kinetics elimination was calculated; a mean distribution volume of 80 mL/kg was also estimated. Pearson’s correlation between ln-transformed serum and daily urine concentrations was good, with r ranging from 0.802 to 0.838. The amount of cC6O4 excreted daily in urine was about 20% of the amount present in serum. The study allowed calculating a half-life for cC6O4 in blood of about 8 days in humans, supporting its much shorter biopersistence in comparison with legacy PFAS. The good correlation between urine and serum cC6O4 suggests urine as a possible non-invasive matrix for biomonitoring. The amount of cC6O4 excreted daily in urine suggests urine as the sole elimination route. Full article
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15 pages, 1589 KiB  
Article
Evaluation of Apical and Molecular Effects of Algae Pseudokirchneriella subcapitata to Cerium Oxide Nanoparticles
by Ntombikayise Mahaye and Ndeke Musee
Toxics 2023, 11(3), 283; https://doi.org/10.3390/toxics11030283 - 19 Mar 2023
Cited by 3 | Viewed by 1456
Abstract
Cerium oxide engineered nanoparticles (nCeO2) are widely used in various applications and are, also, increasingly being detected in different environmental matrixes. However, their impacts on the aquatic environment remain poorly quantified. Hence, there is a need to investigate their effects on [...] Read more.
Cerium oxide engineered nanoparticles (nCeO2) are widely used in various applications and are, also, increasingly being detected in different environmental matrixes. However, their impacts on the aquatic environment remain poorly quantified. Hence, there is a need to investigate their effects on non-target aquatic organisms. Here, we evaluated the cytotoxic and genotoxic effects of <25 nm uncoated-nCeO2 on algae Pseudokirchneriella subcapitata. Apical (growth and chlorophyll a (Chl a) content) and genotoxic effects were investigated at 62.5–1000 µg/L after 72 and 168 h. Results demonstrated that nCeO2 induced significant growth inhibition after 72 h and promotion post 96–168 h. Conversely, nCeO2 induced enhanced Chl a content post 72 h, but no significant changes were observed between nCeO2–exposed and control samples after 168 h. Hence, the results indicate P. subcapitata photosynthetic system recovery ability to nCeO2 effects under chronic-exposure conditions. RAPD-PCR profiles showed the appearance and/or disappearance of normal bands relative to controls; indicative of DNA damage and/or DNA mutation. Unlike cell recovery observed post 96 h, DNA damage persisted over 168 h. Thus, sub-lethal nCeO2-induced toxicological effects may pose a more serious threat to algae than at present anticipated. Full article
(This article belongs to the Section Ecotoxicology)
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16 pages, 3140 KiB  
Article
Biochemical, Genotoxic and Histological Implications of Polypropylene Microplastics on Freshwater Fish Oreochromis mossambicus: An Aquatic Eco-Toxicological Assessment
by Jeyaraj Jeyavani, Ashokkumar Sibiya, Thambusamy Stalin, Ganesan Vigneshkumar, Khalid A. Al-Ghanim, Mian Nadeem Riaz, Marimuthu Govindarajan and Baskaralingam Vaseeharan
Toxics 2023, 11(3), 282; https://doi.org/10.3390/toxics11030282 - 19 Mar 2023
Cited by 14 | Viewed by 2633
Abstract
In recent years, polypropylene microplastic has persisted in freshwater ecosystems and biota, forming ever-growing threats. This research aimed to prepare polypropylene microplastics and evaluate their toxicity to the filter feeder Oreochromis mossambicus. In this research, fish were given a dietary supplement of [...] Read more.
In recent years, polypropylene microplastic has persisted in freshwater ecosystems and biota, forming ever-growing threats. This research aimed to prepare polypropylene microplastics and evaluate their toxicity to the filter feeder Oreochromis mossambicus. In this research, fish were given a dietary supplement of polypropylene microplastics at 100, 500, and 1000 mg/kg for acute (96 h) and sub-acute (14 days) durations to assess toxic effects on liver tissues. FTIR results revealed the presence of polypropylene microplastic in their digestion matter. The ingestion of microplastics in O. mossambicus led to fluctuations in homeostasis, an upsurge in reactive oxygen species (ROS) levels, an alteration in antioxidant parameters, including superoxide dismutase (SOD), catalase (CAT), glutathione-S–transferase (GST), and glutathione peroxidase (GPx); a promotion in the oxidation of lipid molecules; and a denaturation in the neurotransmitter enzyme acetylcholinesterase (AChE). Our data indicated that sustained exposure to microplastics (14 days) produced a more severe threat than acute exposure (96 h). In addition, higher apoptosis, DNA damage (genotoxicity), and histological changes were found in the liver tissues of the sub-acute (14 days) microplastics-treated groups. This research indicated that the constant ingestion of polypropylene microplastics is detrimental to freshwater environments and leads to ecological threats. Full article
(This article belongs to the Special Issue Toxicity Behavior of Microplastics in the Aquatic Ecosystem)
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19 pages, 3988 KiB  
Article
Gut Microbiome-Host Metabolome Homeostasis upon Exposure to PFOS and GenX in Male Mice
by Faizan Rashid, Veronika Dubinkina, Saeed Ahmad, Sergei Maslov and Joseph Maria Kumar Irudayaraj
Toxics 2023, 11(3), 281; https://doi.org/10.3390/toxics11030281 - 19 Mar 2023
Cited by 7 | Viewed by 2736
Abstract
Alterations of the normal gut microbiota can cause various human health concerns. Environmental chemicals are one of the drivers of such disturbances. The aim of our study was to examine the effects of exposure to perfluoroalkyl and polyfluoroalkyl substances (PFAS)—specifically, perfluorooctane sulfonate (PFOS) [...] Read more.
Alterations of the normal gut microbiota can cause various human health concerns. Environmental chemicals are one of the drivers of such disturbances. The aim of our study was to examine the effects of exposure to perfluoroalkyl and polyfluoroalkyl substances (PFAS)—specifically, perfluorooctane sulfonate (PFOS) and 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy) propanoic acid (GenX)—on the microbiome of the small intestine and colon, as well as on liver metabolism. Male CD-1 mice were exposed to PFOS and GenX in different concentrations and compared to controls. GenX and PFOS were found to have different effects on the bacterial community in both the small intestine and colon based on 16S rRNA profiles. High GenX doses predominantly led to increases in the abundance of Clostridium sensu stricto, Alistipes, and Ruminococcus, while PFOS generally altered Lactobacillus, Limosilactobacillus, Parabacteroides, Staphylococcus, and Ligilactobacillus. These treatments were associated with alterations in several important microbial metabolic pathways in both the small intestine and colon. Untargeted LC-MS/MS metabolomic analysis of the liver, small intestine, and colon yielded a set of compounds significantly altered by PFOS and GenX. In the liver, these metabolites were associated with the important host metabolic pathways implicated in the synthesis of lipids, steroidogenesis, and in the metabolism of amino acids, nitrogen, and bile acids. Collectively, our results suggest that PFOS and GenX exposure can cause major perturbations in the gastrointestinal tract, aggravating microbiome toxicity, hepatotoxicity, and metabolic disorders. Full article
(This article belongs to the Special Issue PFAS Toxicology and Metabolism)
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14 pages, 1648 KiB  
Concept Paper
Integrating “One Health” Concepts in the Design of Sustainable Systems for Environmental Use
by Mark S. Johnson and Valerie H. Adams
Toxics 2023, 11(3), 280; https://doi.org/10.3390/toxics11030280 - 19 Mar 2023
Viewed by 1018
Abstract
Ensuring for the national defense requires the use of substances such as energetics, propellants, pyrotechnics, and other materials in environmental applications. Systems that use these materials do so in testing and training environments and must be used in an environmentally sustained manner to [...] Read more.
Ensuring for the national defense requires the use of substances such as energetics, propellants, pyrotechnics, and other materials in environmental applications. Systems that use these materials do so in testing and training environments and must be used in an environmentally sustained manner to ensure success during actual kinetic defensive operations. Environmental and occupational health assessments require a weighted evaluation of toxicity, bioaccumulation, persistence, and environmental fate and transport considerations for each substance in the formulation to include potential combustion products. Data that support these criteria need to be collected in a phased and matrixed approach and considered iteratively as technology advances. Further, these criteria are often considered as disparate and separate; hence, comparing favorable aspects of one may or may not offset detrimental data from another. Here, we describe an approach to the phased collection of environmental, safety, and occupational health (ESOH) information for new systems and substances and provide recommendations for evaluating such data streams in making decisions for use and for evaluating alternatives. Full article
(This article belongs to the Special Issue Toxic Mixtures Evaluation and Management)
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26 pages, 4903 KiB  
Article
A Sublethal Concentration of Sulfoxaflor Has Minimal Impact on Buff-Tailed Bumblebee (Bombus terrestris) Locomotor Behaviour under Aversive Conditioning
by Laura James, Andrew M. Reynolds, Ian R. Mellor and T. G. Emyr Davies
Toxics 2023, 11(3), 279; https://doi.org/10.3390/toxics11030279 - 18 Mar 2023
Viewed by 1412
Abstract
Pesticide exposure has been cited as a key threat to insect pollinators. Notably, a diverse range of potential sublethal effects have been reported in bee species, with a particular focus on effects due to exposure to neonicotinoid insecticides. Here, a purpose-built thermal–visual arena [...] Read more.
Pesticide exposure has been cited as a key threat to insect pollinators. Notably, a diverse range of potential sublethal effects have been reported in bee species, with a particular focus on effects due to exposure to neonicotinoid insecticides. Here, a purpose-built thermal–visual arena was used in a series of pilot experiments to assess the potential impact of approximate sublethal concentrations of the next generation sulfoximine insecticide sulfoxaflor (5 and 50 ppb) and the neonicotinoid insecticides thiacloprid (500 ppb) and thiamethoxam (10 ppb), on the walking trajectory, navigation and learning abilities of the buff-tailed bumblebee (Bombus terrestris audax) when subjected to an aversive conditioning task. The results suggest that only thiamethoxam prevents forager bees from improving in key training parameters (speed and distanced travelled) within the thermal visual arena. Power law analyses further revealed that a speed–curvature power law, previously reported as being present in the walking trajectories of bumblebees, is potentially disrupted under thiamethoxam (10 ppb) exposure, but not under sulfoxaflor or thiacloprid exposure. The pilot assay described provides a novel tool with which to identify subtle sublethal pesticide impacts, and their potential causes, on forager bees, that current ecotoxicological tests are not designed to assess. Full article
(This article belongs to the Special Issue Effect of Pesticides on Insects and Other Arthropods)
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12 pages, 311 KiB  
Perspective
Electronic Cigarette Use during Pregnancy: Is It Harmful?
by M. J. Ruzmyn Vilcassim, Samuel Stowe, Rachel Majumder, Akila Subramaniam and Rachel G. Sinkey
Toxics 2023, 11(3), 278; https://doi.org/10.3390/toxics11030278 - 18 Mar 2023
Viewed by 3393
Abstract
Although combustible cigarette smoking rates have declined in recent years, alternative tobacco product use, particularly electronic cigarette use (“vaping”), has increased among young adults. Recent studies indicate that vaping during pregnancy is on the rise, possibly due to the perception that it is [...] Read more.
Although combustible cigarette smoking rates have declined in recent years, alternative tobacco product use, particularly electronic cigarette use (“vaping”), has increased among young adults. Recent studies indicate that vaping during pregnancy is on the rise, possibly due to the perception that it is a safer alternative to combustible cigarette smoking. However, e-cigarette aerosols may contain several newer, potentially toxic compounds, including some known developmental toxicants that may adversely impact both the mother and the fetus. However, there is paucity of studies that have examined the effects of vaping during pregnancy. While the adverse perinatal outcomes of cigarette smoking during pregnancy are well established, the specific risks associated with inhaling vaping aerosols during pregnancy requires more research. In this article, we discuss the existing evidence and knowledge gaps on the risks of vaping during pregnancy. Studies that investigate vaping-associated systemic exposure and its effects (i.e., biomarker analyses) and maternal and neonatal clinical health outcomes are needed to reach more robust conclusions. We particularly emphasize the need to go beyond comparative studies with cigarettes, and advocate for research that objectively evaluates the safety of e-cigarettes and other alternative tobacco products. Full article
21 pages, 357 KiB  
Review
Monitoring the Health of Coastal Environments in the Pacific Region—A Review
by Louis A. Tremblay, Anthony A. Chariton, Meng-Shuo Li, Yong Zhang, Toshihiro Horiguchi and Joanne I. Ellis
Toxics 2023, 11(3), 277; https://doi.org/10.3390/toxics11030277 - 18 Mar 2023
Cited by 2 | Viewed by 2129
Abstract
Coastal areas provide important ecological services to populations accessing, for example, tourism services, fisheries, minerals and petroleum. Coastal zones worldwide are exposed to multiple stressors that threaten the sustainability of receiving environments. Assessing the health of these valuable ecosystems remains a top priority [...] Read more.
Coastal areas provide important ecological services to populations accessing, for example, tourism services, fisheries, minerals and petroleum. Coastal zones worldwide are exposed to multiple stressors that threaten the sustainability of receiving environments. Assessing the health of these valuable ecosystems remains a top priority for environmental managers to ensure the key stressor sources are identified and their impacts minimized. The objective of this review was to provide an overview of current coastal environmental monitoring frameworks in the Asia-Pacific region. This large geographical area includes many countries with a range of climate types, population densities and land uses. Traditionally, environmental monitoring frameworks have been based on chemical criteria set against guideline threshold levels. However, regulatory organizations are increasingly promoting the incorporation of biological effects-based data in their decision-making processes. Using a range of examples drawn from across the region, we provide a synthesis of the major approaches currently being applied to examine coastal health in China, Japan, Australia and New Zealand. In addition, we discuss some of the challenges and investigate potential solutions for improving traditional lines of evidence, including the coordination of regional monitoring programs, the implementation of ecosystem-based management and the inclusion of indigenous knowledge and participatory processes in decision-making. Full article
(This article belongs to the Special Issue Ecotoxicity of Contaminants in Water and Sediment)
17 pages, 2104 KiB  
Article
Marine Pollutant Tributyltin Affects DNA Methylation and Fitness of Banded Murex (Hexaplex trunculus) Populations
by Maja Šrut, Iva Sabolić, Anita Erdelez, Dorotea Grbin, Martina Furdek Turk, Robert Bakarić, Melita Peharda and Anamaria Štambuk
Toxics 2023, 11(3), 276; https://doi.org/10.3390/toxics11030276 - 17 Mar 2023
Cited by 1 | Viewed by 1271
Abstract
Banded murex, Hexaplex trunculus, is a marine gastropod whose reproductive fitness can be severely affected by very low concentrations of antifouling compound tributyltin (TBT). TBT has strong xenoandrogen impacts on snails, causing the development of imposex (e.g., the superimposition of male sexual [...] Read more.
Banded murex, Hexaplex trunculus, is a marine gastropod whose reproductive fitness can be severely affected by very low concentrations of antifouling compound tributyltin (TBT). TBT has strong xenoandrogen impacts on snails, causing the development of imposex (e.g., the superimposition of male sexual characteristic in females), thereby affecting the fitness of entire populations. TBT is also known as a DNA-demethylating agent and an obesogenic factor. The aim of this study was to unravel the interactions between TBT bioaccumulation, phenotypic responses, and epigenetic and genetic endpoints in native populations of H. trunculus. Seven populations inhabiting environments along the pollution gradient were sampled in the coastal eastern Adriatic. These included sites of intense marine traffic and boat maintenance activity and sites with low anthropogenic impact. Populations inhabiting intermediately and highly polluted sites exhibited higher TBT burdens, higher incidences of imposex, and higher wet masses of snails than populations in lowly polluted sites. Other morphometric traits and cellular biomarker responses did not show clear differentiation among populations in relation to marine traffic/pollution intensity. An analysis of methylation sensitive amplification polymorphism (MSAP) revealed environmentally driven population differentiation and higher epigenetics than genetic within-population diversity. Moreover, decreases in genome-wide DNA methylation coincided with the imposex level and snail mass, suggesting an epigenetic background of the animal phenotypic response. Full article
(This article belongs to the Special Issue Epigenetic Changes in Organisms Stressed by Environmental Pollution)
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19 pages, 4517 KiB  
Article
Status of Ecosystem Services in Abandoned Mining Areas in the Iberian Peninsula: Management Proposal
by María González-Morales, Mª Ángeles Rodríguez-González and Luis Fernández-Pozo
Toxics 2023, 11(3), 275; https://doi.org/10.3390/toxics11030275 - 17 Mar 2023
Cited by 1 | Viewed by 1176
Abstract
An abandoned sphalerite mining area in the southwest (SW) of the Iberian Peninsula was studied to evaluate the impact that the presence of metal(loid)s has on soil and ecosystem health. Five zones were delimited: sludge, dump, scrubland, riparian zone, and dehesa. Critical total [...] Read more.
An abandoned sphalerite mining area in the southwest (SW) of the Iberian Peninsula was studied to evaluate the impact that the presence of metal(loid)s has on soil and ecosystem health. Five zones were delimited: sludge, dump, scrubland, riparian zone, and dehesa. Critical total levels of lead (Pb), zinc (Zn), thallium (Tl), and chromium (Cr), well above the limit indicative of toxicity problems, were found in the areas close to the sources of contamination. Pb-Zn concentrations were very high in the riparian zone, reaching values of 5875 mg/kg Pb and 4570 mg/kg Zn. The whole area is classifiable as extremely contaminated with Tl, with concentrations above 370 mg/kg in the scrubland. Cr accumulation mainly occurred in areas away from the dump, with levels up to 240 mg/kg in the dehesa. In the study area, several plants were found growing luxuriantly despite the contamination. The measured metal(loid)s content is the cause of a significant decrease in ecosystem services, resulting in unsafe soils for food and water production, so the implementation of a decontamination program is advisable. The plant species Retama sphaerocarpa, present in the sludge, scrubland, riparian zone, and dehesa, is postulated as suitable for use in phytoremediation. Full article
(This article belongs to the Special Issue Phytotoxicity of Heavy Metals in Contaminated Soils)
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12 pages, 619 KiB  
Article
Combined Exposure to Multiple Metals and Kidney Function in a Midlife and Elderly Population in China: A Prospective Cohort Study
by Tianci Wang, Liming Zhang, Yujie Liu, Jian Li, Guochong Chen, Hui Zhou, Lugang Yu, Zhongxiao Wan, Chen Dong, Liqiang Qin and Jingsi Chen
Toxics 2023, 11(3), 274; https://doi.org/10.3390/toxics11030274 - 17 Mar 2023
Cited by 2 | Viewed by 1219
Abstract
[Background] Metal exposure is suspected to be correlated to kidney function. However, the combined effects of co-exposing to multiple metals, especially both toxic and protective metals, have not been completely evaluated. [Method] A prospective cohort study was conducted with the “135” cohort for [...] Read more.
[Background] Metal exposure is suspected to be correlated to kidney function. However, the combined effects of co-exposing to multiple metals, especially both toxic and protective metals, have not been completely evaluated. [Method] A prospective cohort study was conducted with the “135” cohort for the evaluation of how plasma metal levels are correlated to kidney function in a midlife and elderly community in southern China. An amount of 1368 subjects without kidney disease at baseline were enrolled in the final analysis. By using linear regression and logistic regression models, the correlation of individual metal values with renal function parameters was assessed. Measuring of the multiple metal exposure level was performed by principal component analysis (PCA). [Results] Diminished renal function, as evaluated based on fast kidney function decline, or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2, was positively associated with the plasma concentrations of chromium and potassium, but it was negatively associated with selenium and iron (p < 0.05). In multiple-metal analyses, linear and logistic regression models showed that the iron and chromium exposure pattern had a protective effect on renal function, whereas the sodium and potassium exposure pattern and the cadmium and lead exposure pattern increased the risk for fast kidney function decline, and eGFR < 60 mL/min/1.73 m2. [Conclusions] Certain metals, including chromium, potassium, selenium, and iron, were correlated with kidney function in a midlife and elderly community in China. In addition, the potential combined influences of co-exposing to multiple metals were observed. Full article
(This article belongs to the Section Metals and Radioactive Substances)
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17 pages, 20042 KiB  
Article
Modulatory Role of Autophagy in Metformin Therapeutic Activity toward Doxorubicin-Induced Nephrotoxicity
by Samar A. Antar, Marwa Abd-Elsalam, Walied Abdo, Ahmed Abdeen, Mohamed Abdo, Liana Fericean, Nahed A. Raslan, Samah F. Ibrahim, Asmaa F. Sharif, Amira Elalfy, Hend E. Nasr, Ahmed B. Zaid, Rania Atia, Ahmed M. Atwa, Mohammed A. Gebba and Amany A. Alzokaky
Toxics 2023, 11(3), 273; https://doi.org/10.3390/toxics11030273 - 16 Mar 2023
Cited by 3 | Viewed by 2207
Abstract
Doxorubicin (DOX) is a frequent chemotherapeutic drug used to treat various malignant tumors. One of the key factors that diminish its therapeutic importance is DOX-induced nephrotoxicity. The first-line oral antidiabetic drug is metformin (Met), which also has antioxidant properties. The purpose of our [...] Read more.
Doxorubicin (DOX) is a frequent chemotherapeutic drug used to treat various malignant tumors. One of the key factors that diminish its therapeutic importance is DOX-induced nephrotoxicity. The first-line oral antidiabetic drug is metformin (Met), which also has antioxidant properties. The purpose of our study was to investigate the underlying molecular mechanisms for the potential protective effects of Met on DOX-triggered nephrotoxicity. Four animal groups were assigned as follows; animals received vehicle (control group), 200 mg/kg Met (Met group), DOX 15 mg/kg DOX (DOX group), and a combination of DOX and Met (DOX/Met group). Our results demonstrated that DOX administration caused marked histological alterations of widespread inflammation and tubular degeneration. Notably, the DOX-induced dramatic up-regulation of the nuclear factor-kappa B/P65 (NF-κB/P65), microtubule-associated protein light chain 3B (LC3B), neutrophil gelatinase-associated lipocalin (NGAL), interleukin-1beta (IL-1β), 8-hydroxy-2′ -deoxyguanosine (8-OHdG), and Beclin-1 in renal tissue. A marked increase in the malondialdehyde (MDA) tissue level and a decrease in the total antioxidant capacity (TAC) were also recorded in DOX-exposed animals. Interestingly, Met could minimize all histopathological changes as well as the disruptions caused by DOX in the aforementioned measures. Thus, Met provided a workable method for suppressing the nephrotoxicity that occurred during the DOX regimen via the deactivation of the Beclin-1/LC3B pathway. Full article
(This article belongs to the Special Issue Antioxidant Capacity of Natural Products for Toxicity Treatment)
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12 pages, 294 KiB  
Article
Toxic Elemental Impurities in Herbal Weight Loss Supplements; A Study Using ICP-OES Microwave-Assisted Digestion
by Ghanim Al-Thani, Adel Ehab Ibrahim, Mohammed Alomairi, Baher I. Salman, Mostafa M. Hegazy, Ahmed Al-Harrasi and Sami El Deeb
Toxics 2023, 11(3), 272; https://doi.org/10.3390/toxics11030272 - 16 Mar 2023
Cited by 3 | Viewed by 1523
Abstract
The tendency of using weight loss herbal preparations is continuously increasing, especially for the widespread consumption of junk food that is characterized by high calories. Weight loss herbal preparations are considered a type of food supplement product, and, as such, the regulations governing [...] Read more.
The tendency of using weight loss herbal preparations is continuously increasing, especially for the widespread consumption of junk food that is characterized by high calories. Weight loss herbal preparations are considered a type of food supplement product, and, as such, the regulations governing their quality control might be minimal. These products could be locally formulated in any country or internationally imported. Being non-controlled products, the herbal weight-loss products may contain high levels of elemental impurities that might exceed the permissible ranges. Moreover, these products contribute to the total daily intake (TDI) of such elements, which might represent concerns about their potential toxicological danger. In this research, the elemental contents in such products were investigated. The inductively coupled plasma with optical emission spectrometer (ICP-OES) was used to determine the levels of 15 elemental contents, namely, Na, K, Ca, Mg, Al, Cu, Fe, Li, Mn, As, Co, Cr, Cd, Ni and Pb. The results showed that seven micro-elements, namely Cd, Co, Ni, Cr, Pb, Li and Cu, were either not detectable or at a concentration much lower than their tolerable limits. However, all studied macro-elements (Na, K, Ca and Mg), together with Fe, were found at considerable, yet safe levels. On the other hand, Mn, Al and As contents showed perturbing levels in some of the studied products. Finally, a conclusion was highlighted for the necessity for stricter surveillance of such herbal products. Full article
(This article belongs to the Section Agrochemicals and Food Toxicology)
18 pages, 5866 KiB  
Article
Interaction of Lead and Cadmium Reduced Cadmium Toxicity in Ficus parvifolia Seedlings
by Yan Li, Xiaomao Cheng, Chengcheng Feng and Xiaoxia Huang
Toxics 2023, 11(3), 271; https://doi.org/10.3390/toxics11030271 - 16 Mar 2023
Cited by 4 | Viewed by 1138
Abstract
Potentially toxic elements (PTEs) pollution occurs widely in soils due to various anthropogenic activities. Lead (Pb) and cadmium (Cd) coexist in soil frequently, threatening plant growth. To explore the interaction effect between Pb and Cd in Ficus parvifolia and the response of plant [...] Read more.
Potentially toxic elements (PTEs) pollution occurs widely in soils due to various anthropogenic activities. Lead (Pb) and cadmium (Cd) coexist in soil frequently, threatening plant growth. To explore the interaction effect between Pb and Cd in Ficus parvifolia and the response of plant physiological characteristics to Pb and Cd stress, we designed a soil culture experiment. The experiment demonstrated that Pb stress improved leaf photosynthesis ability, while Cd stress inhibited it. Furthermore, Pb or Cd stress increased malonaldehyde (MDA) content, but plants were able to reduce it by increasing antioxidant enzyme activities. The presence of Pb could alleviate Cd phytotoxicity in plants by inhibiting Cd uptake and accumulation as well as increasing leaf photosynthesis and antioxidant ability. Pearson correlation analysis illustrated that the variability of Cd uptake and accumulation between Pb and Cd stress was related to plant biomass and antioxidant enzyme activities. This research will offer a new perspective on alleviating Cd phytotoxicity in plants. Full article
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9 pages, 978 KiB  
Article
Toxicity and Sublethal Effects of Diamide Insecticides on Key Non-Target Natural Predators, the Larvae of Coccinella septempunctata L. (Coleoptera: Coccinellidae)
by Yunbo Cong, Jixiang Chen, Yinping Xie, Yingxiu Wang and Chunsheng Cheng
Toxics 2023, 11(3), 270; https://doi.org/10.3390/toxics11030270 - 16 Mar 2023
Cited by 1 | Viewed by 1384
Abstract
Coccinella septempunctata (ladybird) is an extremely important natural predator that feeds on aphids. An assessment of the toxicity of pesticides on environmental organisms is an essential component of Integrated Pest Management (IPM) strategies. This study evaluated diamide insecticides’ toxicity at lethal and 30% [...] Read more.
Coccinella septempunctata (ladybird) is an extremely important natural predator that feeds on aphids. An assessment of the toxicity of pesticides on environmental organisms is an essential component of Integrated Pest Management (IPM) strategies. This study evaluated diamide insecticides’ toxicity at lethal and 30% lethal doses (LR30) against C. septempunctata larvae. The pre-imaginal median lethal doses (LR50) of chlorantraniliprole 10% SC, tetrachlorantraniliprole 10% SC, and broflanilide 10% SC were calculated to be 42.078, 289.516, and 0.0943 g active ingredient (a.i.)/ha, respectively. The mortality tests demonstrated that chlorantraniliprole and tetrachlorantraniliprole are comparatively less toxic to C. septempunctata than broflanilide, which were detected to be highly toxic to C. septempunctata. The mortality rates of the groups treated with the three diamide insecticides tended to stabilize after 96 h, extending to the pre-imaginal stage. Furthermore, when compared to broflanilide, which had a much higher potential risk, the hazard quotient (HQ) values indicated that chlorantraniliprole and tetrachlorantraniliprole have a lower risk potential for C. septempunctata in farmland and off farmland. The LR30 dose induces abnormalities in the development phase 4th-instar larvae weight, pupal weight, and adult weight of treated C. septempunctata. The study emphasizes the importance of assessing the adverse effects of diamide insecticides on natural predator species that serve as biological control agents in agricultural IPM strategies. Full article
(This article belongs to the Section Agrochemicals and Food Toxicology)
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16 pages, 6714 KiB  
Article
Prediction of the Impact of Land Use and Soil Type on Concentrations of Heavy Metals and Phthalates in Soil Based on Model Simulation
by Nataša Stojić, Lato Pezo, Biljana Lončar, Mira Pucarević, Vladimir Filipović, Dunja Prokić, Ljiljana Ćurčić and Snežana Štrbac
Toxics 2023, 11(3), 269; https://doi.org/10.3390/toxics11030269 - 15 Mar 2023
Cited by 4 | Viewed by 1404
Abstract
The main objective of this study is to determine the possibility of predicting the impact of land use and soil type on concentrations of heavy metals (HMs) and phthalates (PAEs) in soil based on an artificial neural network model (ANN). Qualitative analysis of [...] Read more.
The main objective of this study is to determine the possibility of predicting the impact of land use and soil type on concentrations of heavy metals (HMs) and phthalates (PAEs) in soil based on an artificial neural network model (ANN). Qualitative analysis of HMs was performed with inductively coupled plasma–optical emission spectrometry (ICP/OES) and Direct Mercury Analyzer. Determination of PAEs was performed with gas chromatography (GC) coupled with a single quadrupole mass spectrometry (MS). An ANN, based on the Broyden–Fletcher–Goldfarb–Shanno (BFGS) iterative algorithm, for the prediction of HM and PAE concentrations, based on land use and soil type parameters, showed good prediction capabilities (the coefficient of determination (r2) values during the training cycle for HM concentration variables were 0.895, 0.927, 0.885, 0.813, 0.883, 0.917, 0.931, and 0.883, respectively, and for PAEs, the concentration variables were 0.950, 0.974, 0.958, 0.974, and 0.943, respectively). The results of this study indicate that HM and PAE concentrations, based on land use and soil type, can be predicted using ANN. Full article
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18 pages, 7303 KiB  
Article
Quantitative Source Apportionment of Potentially Toxic Elements in Baoshan Soils Employing Combined Receptor Models
by Chunyu Dong, Hao Zhang, Haichan Yang, Zhaoxia Wei, Naiming Zhang and Li Bao
Toxics 2023, 11(3), 268; https://doi.org/10.3390/toxics11030268 - 14 Mar 2023
Cited by 1 | Viewed by 1474
Abstract
Arable soils are crucial for national development and food security; therefore, contamination of agricultural soils from potentially toxic elements (PTEs) is a global concern. In this study, we collected 152 soil samples for evaluation. Considering the contamination factors and using the cumulative index [...] Read more.
Arable soils are crucial for national development and food security; therefore, contamination of agricultural soils from potentially toxic elements (PTEs) is a global concern. In this study, we collected 152 soil samples for evaluation. Considering the contamination factors and using the cumulative index and geostatistical methods, we investigated the contamination levels of PTEs in Baoshan City, China. Using principal component analysis, absolute principal component score-multivariate linear regression, positive matrix factorization, and UNMIX, we analyzed the sources and quantitatively estimated their contributions. The average Cd, As, Pb, Cu, and Zn concentrations were 0.28, 31.42, 47.59, 100.46, and 12.36 mg/kg, respectively. The Cd, Cu, and Zn concentrations exceeded the corresponding background values for Yunnan Province. The combined receptor models showed that natural and agricultural sources contributed primarily to Cd and Cu and As and Pb inputs, accounting for 35.23 and 7.67% pollution, respectively. Industrial and traffic sources contributed primarily to Pb and Zn inputs (47.12%). Anthropogenic activities and natural causes accounted for 64.76 and 35.23% of soil pollution, respectively. Industrial and traffic sources contributed 47.12% to pollution from anthropogenic activities. Accordingly, the control of industrial PTE pollution emissions should be strengthened, and awareness should be raised to protect arable land around roads. Full article
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12 pages, 1063 KiB  
Article
Arsenic Release from Various Sizes of Excavated Crushed Rock Mixed with Soil at Various Ratios under Three Mass Water Contents for Cropland
by Kyo-Suk Lee, Gil-Yong Suh and Doug-Young Chung
Toxics 2023, 11(3), 267; https://doi.org/10.3390/toxics11030267 - 14 Mar 2023
Cited by 1 | Viewed by 1009
Abstract
The purpose of this experiment was to investigate the feasibility of treating arsenopyrite-containing excavated crushed rock (ECR) in cropland by examining the amounts of arsenic released from various sizes of ECR mixed with soils at different ratios under three water levels using a [...] Read more.
The purpose of this experiment was to investigate the feasibility of treating arsenopyrite-containing excavated crushed rock (ECR) in cropland by examining the amounts of arsenic released from various sizes of ECR mixed with soils at different ratios under three water levels using a batch incubation experiment. A total of 4 particle sizes of ECR were mixed with soil from 0% to 100% in 25% increments under three mass water contents such as 15%, 27%, and saturation. The results showed that the amount of As released from ECR mixed with soil was in the order of 27% saturation and 15% for 180 days regardless of the ECR:soil ratios, and the increase in the amount of As released before 90 days was slightly greater than that after 90 days. The maximum and minimum contents of released As were observed at 350.3 mg·kg−1 (ECR:Soil = 100:0, ECR size = 0.0–0.053 mm, and Ɵm = 32.2%), indicating that the smaller the ECR particle size resulted in a higher extractable As concentration. The amount of As released was higher than the relevant standard (25 mg·kg−1), except for ECR with a mixing ratio (25:75) and particle size (4.75–10.0 mm). In conclusion, we assumed that the amount of As released from ECR was influenced by the higher surface area of smaller ECR particle sizes and mass water content, which determine the porosity of the soil. However, further studies are needed on the transport and adsorption of released As depending on the physical and hydrological properties of the soil to determine the size and incorporation rate of ECR into the soil in view of the government standard. Full article
(This article belongs to the Section Toxicity Reduction and Environmental Remediation)
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12 pages, 4781 KiB  
Article
Comparison of ZnO Nanoparticles Prepared by Precipitation and Combustion for UV and Sunlight-Driven Photocatalytic Degradation of Methylene Blue
by Sucheewan Krobthong, Tipawan Rungsawang and Sutthipoj Wongrerkdee
Toxics 2023, 11(3), 266; https://doi.org/10.3390/toxics11030266 - 14 Mar 2023
Cited by 14 | Viewed by 1844 | Correction
Abstract
ZnO nanoparticles (NPs) were comparatively synthesized via precipitation and combustion techniques. The ZnO NPs synthesized via precipitation and combustion exhibited similar polycrystalline hexagonal wurtzite structures. The large crystal sizes of ZnO NPs were obtained from the ZnO precipitation in comparison with those from [...] Read more.
ZnO nanoparticles (NPs) were comparatively synthesized via precipitation and combustion techniques. The ZnO NPs synthesized via precipitation and combustion exhibited similar polycrystalline hexagonal wurtzite structures. The large crystal sizes of ZnO NPs were obtained from the ZnO precipitation in comparison with those from the ZnO combustion, while the particle sizes were in the same range. The functional analysis implied that the ZnO structures had surface defects. Moreover, absorbance measurement showed the same absorbance range in ultraviolet light. In the photocatalytic degradation of methylene blue, ZnO precipitation exhibited higher degradation performance than ZnO combustion. This was attributed to the larger crystal sizes of ZnO NPs, which provided an enduring carrier movement at semiconductor surfaces and reduced electron-hole recombination. Thus, the crystallinity of ZnO NPs can be considered an important factor in photocatalytic activity. Furthermore, precipitation is an interesting synthesizing method for preparing ZnO NPs with large crystal sizes. Full article
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14 pages, 2381 KiB  
Article
Source Apportionment and Model Applicability of Heavy Metal Pollution in Farmland Soil Based on Three Receptor Models
by Jiawei Ma, Kaining Lanwang, Shiyan Liao, Bin Zhong, Zhenhua Chen, Zhengqian Ye and Dan Liu
Toxics 2023, 11(3), 265; https://doi.org/10.3390/toxics11030265 - 13 Mar 2023
Cited by 3 | Viewed by 1322
Abstract
The identification of the source of heavy metal pollution and its quantification are the prerequisite of soil pollution control. The APCS-MLR, UNMIX and PMF models were employed to apportion pollution sources of Cu, Zn, Pb, Cd, Cr and Ni of the farmland soil [...] Read more.
The identification of the source of heavy metal pollution and its quantification are the prerequisite of soil pollution control. The APCS-MLR, UNMIX and PMF models were employed to apportion pollution sources of Cu, Zn, Pb, Cd, Cr and Ni of the farmland soil in the vicinity of an abandoned iron and steel plant. The sources, contribution rates and applicability of the models were evaluated. The potential ecological risk index revealed greatest ecological risk from Cd. The results of source apportionment illustrated that the APCS-MLR and UNMIX models could verify each other for accurate allocation of pollution sources. The industrial sources were the main sources of pollution (32.41~38.42%), followed by agricultural sources (29.35~31.65%) and traffic emission sources (21.03~21.51%); and the smallest proportion was from natural sources of pollution (11.2~14.42%). The PMF model was easily affected by outliers and its fitting degree was not ideal, leading to be unable to get more accurate results of source analysis. The combination of multiple models could effectively improve the accuracy of pollution source analysis of soil heavy metals. These results provide some scientific basis for further remediation of heavy metal pollution in farmland soil. Full article
(This article belongs to the Section Toxicity Reduction and Environmental Remediation)
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12 pages, 293 KiB  
Article
Determinants Analysis Regarding Household Chemical Indoor Pollution
by Paolo Montuori, Mariagiovanna Gioia, Michele Sorrentino, Fabiana Di Duca, Francesca Pennino, Giuseppe Messineo, Maria Luisa Maccauro, Simonetta Riello, Ugo Trama, Maria Triassi and Antonio Nardone
Toxics 2023, 11(3), 264; https://doi.org/10.3390/toxics11030264 - 13 Mar 2023
Cited by 3 | Viewed by 1638
Abstract
Indoor household pollution is not yet sufficiently studied in the general population. Over 4 million people die prematurely every year due to air pollution in households. This study aimed to propose quantitative data research through the administration of a KAP (Knowledge, Attitudes, and [...] Read more.
Indoor household pollution is not yet sufficiently studied in the general population. Over 4 million people die prematurely every year due to air pollution in households. This study aimed to propose quantitative data research through the administration of a KAP (Knowledge, Attitudes, and Practices) Survey Questionnaire. This cross-sectional study administered questionnaires to adults from the metropolitan city of Naples (Italy). Three Multiple Linear Regression Analyses (MLRA) were developed, including Knowledge, Attitudes, and Behavior regarding household chemical air pollution and the related risks. One thousand six hundred seventy subjects received a questionnaire to be filled out and collected anonymously. The mean age of the sample was 44.68 years, ranging from 21–78 years. Most of the people interviewed (76.13%) had good attitudes toward house cleaning, and 56.69% stated paying attention to cleaning products. Results of the regression analysis indicated that positive attitudes were significantly higher among subjects who graduated, with older age, male and non-smokers, but they were correlated with lower knowledge. In conclusion, a behavioral and attitudinal program targeted those with knowledge, such as younger subjects with high educational levels, but do not engage in correct practices towards household indoor chemical pollution. Full article
12 pages, 2080 KiB  
Article
Electrokinetic Remediation of Zn-Polluted Soft Clay Using a Novel Electrolyte Chamber Configuration
by Zhaohua Sun, Wanxia Tan, Jian Gong and Guowei Wei
Toxics 2023, 11(3), 263; https://doi.org/10.3390/toxics11030263 - 12 Mar 2023
Viewed by 1323
Abstract
This study investigated a novel electrolyte chamber configuration for heavy-metal-contaminated fine-grained soil to reduce the leakage of electrolyte solution and alleviate secondary pollution, finally promoting the electrokinetic remediation (EKR) potential to be scaled up for application. Experiments were conducted on clay spiked with [...] Read more.
This study investigated a novel electrolyte chamber configuration for heavy-metal-contaminated fine-grained soil to reduce the leakage of electrolyte solution and alleviate secondary pollution, finally promoting the electrokinetic remediation (EKR) potential to be scaled up for application. Experiments were conducted on clay spiked with Zn to investigate the feasibility of the novel EKR configuration and the effect of different electrolyte compositions on the electrokinetic remedial efficiency. The results show that the electrolyte chamber situated above the soil surface is promising for the remediation of Zn-contaminated soft clay. Using 0.2 M citric acid as the anolytes and catholytes was an excellent choice for pH control in the soil and the electrolytes. Through this, the removal efficiency in different soil sections was relatively uniform and more than 90% of the initial Zn was removed. The supplementing of electrolytes resulted in the water content in the soil being distributed evenly and finally sustained at approximately 43%. Consequently, this study proved that the novel EKR configuration is suitable for fine-grained soil contaminated with Zn. Full article
(This article belongs to the Section Toxicity Reduction and Environmental Remediation)
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14 pages, 1540 KiB  
Article
Effects of Shellfish and Organic Fertilizer Amendments on Soil Nutrients and Tea Yield and Quality
by Wenbin Liu, Shiyu Cui, Jiawei Ma, Dongtao Wu, Zhengqian Ye and Dan Liu
Toxics 2023, 11(3), 262; https://doi.org/10.3390/toxics11030262 - 12 Mar 2023
Cited by 4 | Viewed by 2002
Abstract
Soil acidification in tea plantations leads to an excessive heavy metal content in tea, decreasing its yield and quality. How to apply shellfish and organic fertilizers to improve soil and ensure the safe production of tea is still not clear. A two-year field [...] Read more.
Soil acidification in tea plantations leads to an excessive heavy metal content in tea, decreasing its yield and quality. How to apply shellfish and organic fertilizers to improve soil and ensure the safe production of tea is still not clear. A two-year field experiment was conducted in tea plantations in which the soil was characterized by a pH of 4.16 and concentrations of lead (Pb) (85.28 mg/kg) and cadmium (Cd) (0.43 mg/kg) exceeding the standard. We used shellfish amendments (750, 1500, 2250 kg/ha) and organic fertilizers (3750, 7500 kg/ha) to amend the soils. The experimental results showed that compared with the treatment without any amendment (CK), the soil pH increased by 0.46 on average; the soil available nitrogen, phosphorus, and potassium contents increased by 21.68%, 19.01%, and 17.51% respectively; and the soil available Pb, Cd, Cr, and As contents decreased by 24.64%, 24.36%, 20.83%, and 26.39%, respectively. In comparison to CK, the average yield of tea also increased by 90.94 kg/ha; tea polyphenols, free amino acids, caffeine, and water extract increased by 9.17%, 15.71%, 7.54%, and 5.27%, respectively; and the contents of Pb, Cd, As, and Cr in the tea decreased significantly (p < 0.05) by 29.44–61.38%, 21.43–61.38%, 10.43–25.22%, and 10.00–33.33%, respectively. The greatest effects on all parameters occurred with the largest amendment of both shellfish (2250 kg/ha) and organic fertilizer (7500 kg/ha) combined. This finding suggests that the optimized amendment of shellfish could be used as a technical measure to improve the health quality of both soil and tea in acidified tea plantations in the future. Full article
(This article belongs to the Special Issue Quality Control and Safety Management of Tea)
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