Toxics

23 pages, 9021 KiB

Open AccessArticle

Population Cohort-Validated PM_2.5-Induced Gene Signatures: A Machine Learning Approach to Individual Exposure Prediction

by Yu-Chung Wei, Wen-Chi Cheng, Pinpin Lin, Zhi-Yao Zhang, Chi-Hsien Chen, Chih-Da Wu, Yue Leon Guo and Hung-Jung Wang

Toxics 2025, 13(7), 562; https://doi.org/10.3390/toxics13070562 - 30 Jun 2025

Abstract

Transcriptomic profiling has shown that exposure to PM_2.5, a common air pollutant, can modulate gene expression, which has been linked to negative health effects and diseases. However, there are few population-based cohort studies on the association between PM_2.5 exposure and [...] Read more.

Transcriptomic profiling has shown that exposure to PM_2.5, a common air pollutant, can modulate gene expression, which has been linked to negative health effects and diseases. However, there are few population-based cohort studies on the association between PM_2.5 exposure and specific gene set expression. In this study, we used an unbiased transcriptomic profiling approach to examine gene expression in a mouse model exposed to PM_2.5 and to identify PM_2.5-responsive genes. The gene expressions were further validated in both the human cell lines and a population-based cohort study. Two cohorts of healthy older adults (aged ≥ 65 years) were recruited from regions characterized by differing levels of PM_2.5. Logistic regression and decision tree algorithms were then utilized to construct predictive models for PM_2.5 exposure based on these gene expression profiles. Our results indicated that the expression of five genes (FAM102B, PPP2R1B, OXR1, ITGAM, and PRP38B) increased with PM_2.5 exposure in both cell-based assay and population-based cohort studies. Furthermore, the predictive models demonstrated high accuracy in classifying high-and-low PM_2.5 exposure, potentially supporting the integration of gene biomarkers into public health practices. Full article

(This article belongs to the Section Air Pollution and Health)

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28 pages, 2584 KiB

Open AccessArticle

Geochemical Characteristics and Risk Assessment of PTEs in the Supergene Environment of the Former Zoige Uranium Mine

by Na Zhang, Zeming Shi, Chengjie Zou, Yinghai Zhu and Yun Hou

Toxics 2025, 13(7), 561; https://doi.org/10.3390/toxics13070561 - 30 Jun 2025

Abstract

Carbonaceous–siliceous–argillaceous rock-type uranium deposits, a major uranium resource in China, pose significant environmental risks due to heavy metal contamination. Geochemical investigations in the former Zoige uranium mine revealed elevated As, Cd, Cr, Cu, Ni, U, and Zn concentrations in soils and sediments, particularly [...] Read more.

Carbonaceous–siliceous–argillaceous rock-type uranium deposits, a major uranium resource in China, pose significant environmental risks due to heavy metal contamination. Geochemical investigations in the former Zoige uranium mine revealed elevated As, Cd, Cr, Cu, Ni, U, and Zn concentrations in soils and sediments, particularly at river confluences and downstream regions, attributed to leachate migration from ore bodies and tailings ponds. Surface samples exhibited high Cd bioavailability. The integrated BCR and mineral analysis reveals that Acid-soluble and reducible fractions of Ni, Cu, Zn, As, and Pb are governed by carbonate dissolution and Fe-Mn oxide dynamics via silicate weathering, while residual and oxidizable fractions show weak mineral-phase dependencies. Positive Matrix Factorization identified natural lithogenic, anthropogenic–natural composite, mining-related sources. Pollution assessments using geo-accumulation index and contamination factor demonstrated severe contamination disparities: soils showed extreme Cd pollution, moderate U, As, Zn contamination, and no Cr, Pb pollution (overall moderate risk); sediments exhibited extreme Cd pollution, moderate Ni, Zn, U levels, and negligible Cr, Pb impacts (overall extreme risk). USEPA health risk models indicated notable non-carcinogenic (higher in adults) and carcinogenic risks (higher in children) for both age groups. Ecological risk assessments categorized As, Cr, Cu, Ni, Pb, and Zn as low risk, contrasting with Cd (extremely high risk) and sediment-bound U (high risk). These findings underscore mining legacy as a critical environmental stressor and highlight the necessity for multi-source pollution mitigation strategies. Full article

(This article belongs to the Special Issue Assessment and Remediation of Heavy Metal Contamination in Soil)

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19 pages, 3316 KiB

Open AccessArticle

Ecological Risk and Human Health Assessment of Heavy Metals in Sediments of Datong Lake

by Gao Li, Rui Chen, Zhen Li, Xin Wu, Kui Xiang, Chiheng Wang and Yi Peng

Toxics 2025, 13(7), 560; https://doi.org/10.3390/toxics13070560 - 30 Jun 2025

Abstract

Heavy metal pollution of lake sediments is one of the prominent ecological and environmental problems worldwide, and it is of great significance to conduct research on heavy metal pollution in lake sediments to protect the ecological environment, safeguard human health, and promote sustainable [...] Read more.

Heavy metal pollution of lake sediments is one of the prominent ecological and environmental problems worldwide, and it is of great significance to conduct research on heavy metal pollution in lake sediments to protect the ecological environment, safeguard human health, and promote sustainable development. As an integral part of Dongting Lake, Datong Lake holds a crucial ecological position. More than 10 years ago, due to a series of factors, including excessive fertilizer application and fishing, the water quality of Datong Lake declined, resulting in varying degrees of contamination by Cd, Mn, and other heavy metals in the sediments. After 2017, Datong Lake began to establish a mechanism for protecting and managing the lake, and its ecological and environmental problems have been significantly improved. To clarify the current situation of heavy metal contamination in the sediments of Datong Lake, 15 sediment samples were collected from the lake, and the contents of soil heavy metals Cd, As, Pb, Cr, Cu, Mn, Ni, and Zn were determined. A Monte Carlo simulation was introduced to carry out the ecological and human health risk evaluation of the sediments in the study area to overcome the problem of low reliability of the results of ecological and human health risk evaluation due to the randomness and incompleteness of the environmental data as well as the differences in the human body parameters. The results and conclusions show that (1) the average values of Cd, Pb, Cr, Cu, Mn, Ni, and Zn contents in the sediments of Datong Lake are higher than the background values of soil elements in the sediments of Dongting Lake, and the average values of As contents of heavy metals are lower than the background values of the soil, and the heavy metal contamination in the sediments in the study area is dominated by slight contamination, and the possibility of point-source contamination is slight. (2) The results of both the Geo-accumulation index and Enrichment factor evaluation showed that the degree of heavy metal contamination of sediments was Ni > Cu > Cr > Mn > Cd > Pb > Zn > As. (3) The average value of the single ecological risk index of heavy metal elements, in descending order, was as follows: Cd > As > Pb > Cu > Ni > Cr > Zn > Mn; all the heavy metal elements were at the level of light pollution, and the average value of the comprehensive ecological risk index was 32.83, which is a slight ecological risk level. (4) Both non-carcinogenic and carcinogenic risks for all populations in the study area remain low following heavy metal exposure via ingestion and dermal pathways. Ecological and health risk assessments identified As and Cd as exhibiting significantly higher sensitivity than other heavy metals. Consequently, continuous monitoring and source-tracking of these elements are recommended to safeguard long-term ecological integrity and public health in the region. Full article

(This article belongs to the Section Metals and Radioactive Substances)

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95 pages, 3664 KiB

Open AccessReview

Research Progress on Chemical Compositions, Pharmacological Activities, and Toxicities of Quinone Compounds in Traditional Chinese Medicines

by Zhe Li, Rui Yao, Hong Guo, Wenguang Jing, Xiaohan Guo, Xiaoqiu Liu, Yingni Pan, Pei Cao, Lei Zhang, Jianbo Yang, Xianlong Cheng and Feng Wei

Toxics 2025, 13(7), 559; https://doi.org/10.3390/toxics13070559 - 30 Jun 2025

Abstract

With the continuous development of research on natural medicines, quinone compounds have become increasingly important in the research field of chemical constituents of natural treatments. However, there is a lack of in-depth and systematic collation of their types, distribution, pharmacological activities, and potential [...] Read more.

With the continuous development of research on natural medicines, quinone compounds have become increasingly important in the research field of chemical constituents of natural treatments. However, there is a lack of in-depth and systematic collation of their types, distribution, pharmacological activities, and potential toxicities. This article comprehensively reviews the structural types, biogenetic pathways, extraction and separation methods, structural identification techniques, pharmacological activities, and toxicities of quinone compounds. It is found that the main difficulties in the research of quinone compounds lie in the cumbersome traditional separation and structural identification processes, as well as the insufficient in-depth studies on the mechanisms of their activities and toxicities. This review aims to provide a reference for research on quinone compounds in natural products and offer ideas and suggestions for subsequent in-depth exploration of the pharmacological activities of quinone compounds, prevention and control of their toxicities, and the realization of rational drug use. Full article

(This article belongs to the Section Drugs Toxicity)

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23 pages, 7080 KiB

Open AccessArticle

Distribution Characteristics of High-Background Elements and Assessment of Ecological Element Activity in Typical Profiles of Ultramafic Rock Area

by Jingtao Shi, Junjian Liu, Suduan Hu and Jiangyulong Wang

Toxics 2025, 13(7), 558; https://doi.org/10.3390/toxics13070558 - 30 Jun 2025

Abstract

This study investigates the weathering crust composite of serpentine, pyroxenite and granite in the Niangniangmiao area, the weathering crusts inside and outside the mining area were compared respectively, systematically revealing the distribution patterns, migration pathways, and ecological element activity characteristics of high-background elements [...] Read more.

This study investigates the weathering crust composite of serpentine, pyroxenite and granite in the Niangniangmiao area, the weathering crusts inside and outside the mining area were compared respectively, systematically revealing the distribution patterns, migration pathways, and ecological element activity characteristics of high-background elements (e.g., chromium (Cr) and nickel (Ni)) through precise sampling, the Tessier five-step sequential extraction method, and a migration coefficient model. Key findings include: (1) Element distribution and controlling mechanisms: The average Cr and Ni contents in the serpentinite profile are significantly higher than those in pyroxenite. However, the semi-weathered pyroxenite layer exhibits an inverted Cr enrichment ratio in relation to serpentinite, 1.8× and 1.2×, respectively, indicating that mineral metasomatic sequences driven by hydrothermal alteration dominate element differentiation; the phenomenon of inverted enrichment of high-background elements occurs in the weathering crust profiles of the two basic rocks. (2) Dual impacts of mining activities on heavy metal enrichment: Direct mining increases topsoil Cr content in serpentinite by 40% by disrupting parent material homology, while indirect activities introduce exogenous Zn and Cd (Spearman correlation coefficients with Cr/Ni are from ρ = 0.58 to ρ = 0.72). Consequently, the bioavailable fraction ratio value of Ni outside the mining area (21.14%) is significantly higher than that within the area (14.30%). (3) Element speciation and ecological element activity: Over 98% of Cr in serpentine exists in residual fractions, whereas the Fe-Mn oxide-bound fraction (F3) of Cr in extra-mining pyroxenite increases to 5.15%. The element activity in ecological systems ranking of Ni in soil active fractions (F1 + F2 = 15%) follows the order: granite > pyroxenite > serpentine. Based on these insights, a scientific foundation for targeted remediation in high-background areas (e.g., prioritizing the treatment of semi-weathered pyroxenite layers) can be provided. Full article

(This article belongs to the Section Exposome Analysis and Risk Assessment)

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4 pages, 139 KiB

Open AccessEditorial

Integrated Remediation Processes Toward Heavy Metal-Contaminated Environment

by Luhua Jiang, Liang Hu and Zhigang Yu

Toxics 2025, 13(7), 557; https://doi.org/10.3390/toxics13070557 - 30 Jun 2025

Abstract

This Editorial introduces the Special Issue titled “Integrated Remediation Processes toward Heavy Metal-Contaminated Environment” [...] Full article

(This article belongs to the Special Issue Integrated Remediation Processes toward Heavy Metal-Contaminated Environment)

28 pages, 829 KiB

Open AccessSystematic Review

Toxic Metal Content in Deciduous Teeth: A Systematic Review

by Ireneusz Zawiślak, Sylwia Kiryk, Jan Kiryk, Agnieszka Kotela, Julia Kensy, Mateusz Michalak, Jacek Matys and Maciej Dobrzyński

Toxics 2025, 13(7), 556; https://doi.org/10.3390/toxics13070556 - 30 Jun 2025

Abstract

Deciduous teeth accumulate toxic metals until fully mineralized, making them a stable biological matrix for assessing chronic exposure during fetal and early postnatal life. Their metal content is influenced by environmental factors (e.g., industrial areas, mining sites) and individual factors (e.g., maternal diet, [...] Read more.

Deciduous teeth accumulate toxic metals until fully mineralized, making them a stable biological matrix for assessing chronic exposure during fetal and early postnatal life. Their metal content is influenced by environmental factors (e.g., industrial areas, mining sites) and individual factors (e.g., maternal diet, early nutrition, passive smoking). The aim of this study was to evaluate the toxic metal content in deciduous teeth and to identify factors contributing to its accumulation, as well as possible health implications. A systematic review was conducted in accordance with the PRISMA guidelines and following the PICO framework. Quality assessment was assessed using the Joanna Briggs Institute (JBI) checklist for quasi-experimental studies. The literature search was carried out in the PubMed, Scopus, and Web of Science databases using the following keywords: deciduous, milk, primary, decidua, teeth, dentition, heavy metal, toxic metals. A total of 134 articles were initially identified, with 95 remaining after duplicate removal. After screening, 75 articles were excluded: 71 did not meet the inclusion criteria, 3 were not available in English, and 1 lacked full-text access. Ultimately, 20 studies were included in the review. Toxic metal concentrations were determined using various analytical techniques, mainly inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS). Higher levels of metals, especially lead, were observed in the teeth of children residing in industrial areas, near mines, or in regions affected by armed conflict. Although two out of five studies indicated a possible link between fathers’ smoking habits and elevated lead concentrations, no definitive relationship was established between secondhand smoke exposure and the levels of lead and cadmium found in dental tissue. Similarly, no definitive relationship was identified between mercury and lead content and the prevalence of autism. However, lower manganese levels were associated with the presence of autistic traits, weaker verbal performance, and reduced memory capacity. In conclusion, deciduous teeth represent a valuable biological material for assessing chronic prenatal and early postnatal exposure to toxic metals, which may serve as a starting point for further research into diseases of unknown etiology, such as autism, and in the future may have clinical significance in their prevention and treatment. And it is also important for monitoring environmental pollution levels. Full article

(This article belongs to the Section Metals and Radioactive Substances)

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19 pages, 2415 KiB

Open AccessArticle

Coupled Effects of Polyethylene Microplastics and Cadmium on Soil–Plant Systems: Impact on Soil Properties and Cadmium Uptake in Lettuce

by Zhiqin Zhang and Boyuan Bi

Toxics 2025, 13(7), 555; https://doi.org/10.3390/toxics13070555 - 30 Jun 2025

Abstract

Microplastics (MPs) and cadmium (Cd) in the soil environment are expected to pose a serious threat to agricultural production. However, the effect of the interaction between them on the soil–plant system and the mechanism of MPs on plant Cd uptake are still unclear. [...] Read more.

Microplastics (MPs) and cadmium (Cd) in the soil environment are expected to pose a serious threat to agricultural production. However, the effect of the interaction between them on the soil–plant system and the mechanism of MPs on plant Cd uptake are still unclear. Therefore, the effects of different concentrations of polyethylene (PE-MPs, 0, 1.0% and 2.0%), alone or combined with Cd, on soil properties, plant growth and Cd uptake were investigated through pot experiments. The results showed that the single contamination of MPs and Cd and their interaction (MPs + Cd) significantly decreased soil moisture and pH; however, it increased soil organic matter (SOM) and total nitrogen (TN). Soil urease and catalase activities were significantly decreased and sucrase and alkaline phosphatase activities were increased with or without Cd addition. The exposure of PE and Cd, alone or combined, significantly and negatively affected plant biomass, photosynthetic parameters, and caused oxidative damage to plants, and the overall toxicity to plants increases with the increase in PE concentration. Moreover, co-pollution causes greater plant toxicity than the individual pollution of PE or Cd. Plants can resist oxidative stress by increasing superoxide dismutase (SOD) and peroxidase (POD) activities. The heat map showed that soil environmental factors were significantly correlated with plant growth; and the results of redundancy analysis (RDA) indicated that for plant physiological characteristics, soil properties under PE, alone or co-contaminated with Cd, explained a total of 85.77% and 97.45%, respectively. This indicated that the alteration of the soil microenvironment is the key factor influencing plant growth. The results of the partial least squares path model (PLS-PM) indicated that plant oxidative damage and biomass had significant positive and negative direct effects on plant Cd uptake, respectively. The linear model of relative importance (%) further revealed in depth that soil moisture (relative importance: 33.60%) and plant biomass (relative importance: 20.23%) were, respectively, regarded as the most important soil environmental factors and plant indicators affecting their Cd uptake. This study provided theoretical support for assessing the risks of MPs and Cd co-pollution to agricultural ecosystems. Full article

(This article belongs to the Section Emerging Contaminants)

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17 pages, 1726 KiB

Open AccessArticle

Risk Assessment and Correlation Analysis of Potentially Toxic Element Pollution in Soil and Crops: A Case Study in a Typical Area

by Jiufen Liu, Cang Gong, Yinji Ba, Shuliang Liu, Huiyun Wan, Xiaofeng Zhao, Ziqi Li, Xiaohuang Liu and Zhongfang Yang

Toxics 2025, 13(7), 554; https://doi.org/10.3390/toxics13070554 - 30 Jun 2025

Abstract

Soil contamination with potentially toxic elements (PTEs) not only poses potential ecological risks (RI) but also leads to human health risks (HI) through the uptake of potentially toxic elements by crops. However, most studies primarily focus on potentially toxic element contamination in either [...] Read more.

Soil contamination with potentially toxic elements (PTEs) not only poses potential ecological risks (RI) but also leads to human health risks (HI) through the uptake of potentially toxic elements by crops. However, most studies primarily focus on potentially toxic element contamination in either soil or crops, often neglecting the intrinsic connections between soil and crop contamination risks. In reality, some regions may exhibit severe soil PTE exceedances, yet the PTE levels in crops may not necessarily exceed regulatory limits, resulting in human health risks that are not uniformly high. This study investigated a typical area with severe soil PTE pollution caused by wastewater from electroplating, smelting, and ore beneficiation industries, and conducted risk assessments on soil and crops. The research aims to elucidate the differences in soil and crop PTE contamination risks and the correlations between PTE concentrations in soil and crops. Results showed that Cd was the most severe PTE contaminant in the soil in the study area, with an average concentration of 1.11 mg/kg and a maximum concentration of 7.30 mg/kg. However, the average concentrations of eight PTEs in crops were all below the standard limits for cereal crops specified in the Food Safety National Standard for Pollutant Limits in Foods (GB 2726-2022). Cd was identified as the most severe PTE contaminant in the soil, resulting in the highest RI (836) in the MY sub-region of the study area. However, Cr in crops contributed the most to health risk (63.5%), leading to the highest HI (7.1) in sub-region MY. Despite Cd being the most severely polluting PTE in soil, its contribution to human health risk through crops was relatively low, ranging from 2.82% to 9.90%. This discrepancy in pollution risks indicates that a PTE causing severe soil contamination may not necessarily result in significant human health risks via crop uptake. Correlation and regression analyses revealed that soil PTEs had the greatest impact on Cd levels in crops. Soil Ni, Cd, Cu, As, and Zn exhibited different synergistic or antagonistic effects on crop PTE uptake. Notably, soil Cd content showed a highly significant positive regression relationship with Cd, Cr, and Ni concentrations in crops. Overall, the influence of soil PTEs on crop PTEs varied significantly, and the spatial differentiation characteristics of PTEs in soil and crops differed. For PTEs with high spatial differentiation, localized and precise management measures should be implemented. Conversely, for PTEs with low spatial differentiation, unified risk management and control measures can be adopted. Full article

(This article belongs to the Section Metals and Radioactive Substances)

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18 pages, 1849 KiB

Open AccessArticle

Composting as a Sustainable Approach for Managing Mercury-Contaminated Aquatic Biomass

by María José Caraballo-Laza, Diana Marcela Ossa-Henao, Iván Urango-Cardenas, Mauricio Rosso-Pinto, Jean Remy Davée Guimarães, Roberth Paternina-Uribe, Yuber Palacios-Torres and José Marrugo-Negrete

Toxics 2025, 13(7), 553; https://doi.org/10.3390/toxics13070553 - 29 Jun 2025

Abstract

In this study, composting as an alternative approach for managing mercury-contaminated biomass in water bodies affected by gold mining in the Choco department was evaluated. A single-factor experiment with three treatments containing varying amounts of Eleocharis interstincta biomass sourced from mercury-contaminated sites was [...] Read more.

In this study, composting as an alternative approach for managing mercury-contaminated biomass in water bodies affected by gold mining in the Choco department was evaluated. A single-factor experiment with three treatments containing varying amounts of Eleocharis interstincta biomass sourced from mercury-contaminated sites was designed. During the composting process, physicochemical parameters were monitored such as temperature, pH, and electrical conductivity, while analyzing the behavior of mercury through mass balance assessments. Additionally, we determined the bioavailability of mercury in the final compost and characterized the physicochemical parameters of each compost sample. The mercury mass balance indicated a decrease in the total mercury content in the initial biomass over the composting period of 170 days. However, the total mercury concentration in the final compost increased due to the transformation and subsequent reduction of the original biomass. Mercury speciation analysis revealed that mercury was predominantly associated with the less bioavailable fractions (F4 and F5), suggesting its stabilization and low availability to biota. Therefore, the final compost has the potential to restore degraded soils by improving moisture retention, porosity, and soil fertility, thereby promoting plant growth. However, it does not fully meet the national and international technical standards for solid organic fertilizers or compost. Full article

(This article belongs to the Special Issue Mercury Cycling and Health Effects—2nd Edition)

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11 pages, 392 KiB

Open AccessArticle

Fighting Lead Poisoning: Effective Conditions for Home-Based Education, Housing Remediation, and Relocation

by Hugues de Barberin-Barberini, Elisabeth Jouve, Jean-Christophe Dubus, Karine Hadji and Remi Laporte

Toxics 2025, 13(7), 552; https://doi.org/10.3390/toxics13070552 - 29 Jun 2025

Abstract

Background—Against childhood lead poisoning, removing lead exposure is the main measure, but how to do it effectively has not been fully established. Our objective was to determine the impact of several interventions (education, housing remediation, and relocation) on children’s blood lead levels. Methods—A [...] Read more.

Background—Against childhood lead poisoning, removing lead exposure is the main measure, but how to do it effectively has not been fully established. Our objective was to determine the impact of several interventions (education, housing remediation, and relocation) on children’s blood lead levels. Methods—A historical cohort of childhood lead poisoning was drawn in Marseille, France, from 2011 to 2018. A generalized mixed model was developed to study the kinetics of blood lead levels. Results—We included 151 children, with 56% living in legal substandard housing and others living in slums. Medical follow-up (median: 612 days) included 492 blood samples. In legal substandard housing, blood lead level decrease was significantly associated with every intervention. In slums, blood lead level decrease was significantly associated with housing relocation and education, although to a lesser extent. Conclusions—Every intervention contributed to reducing blood lead levels in substandard housing. Educational intervention is rapidly implemented. Housing remediation follows a long-lasting but effective legal procedure. Some families get housing relocation, depending on their financial resources or whether they are eligible for social housing. In slums, access to legal housing is the most effective against environmental exposure and education has a wider impact on health literacy. Full article

(This article belongs to the Section Toxicity Reduction and Environmental Remediation)

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22 pages, 317 KiB

Open AccessReview

Glyphosate-Based Herbicides and Their Potential Impact on the Microbiota of Social Bees

by Juan P. Muñoz, Diego Soto-Jiménez, Anghel Brito and Claudio Quezada-Romegialli

Toxics 2025, 13(7), 551; https://doi.org/10.3390/toxics13070551 - 29 Jun 2025

Abstract

Bee pollination is essential for terrestrial ecosystems and crop production. However, the species richness of wild bees and other pollinators has declined over the past 50 years, with some species experiencing dramatic decreases. A key factor in maintaining bee health is their gut [...] Read more.

Bee pollination is essential for terrestrial ecosystems and crop production. However, the species richness of wild bees and other pollinators has declined over the past 50 years, with some species experiencing dramatic decreases. A key factor in maintaining bee health is their gut microbiota, which plays an essential role in digestion, nutrient absorption, immune function, and resistance to pathogens. Disruptions to this microbiota can severely impact bee health, rendering them more susceptible to diseases and environmental stressors. Glyphosate, one of the most widely used herbicides, has been extensively studied for its effects on various organisms, with increasing evidence indicating its potential to disrupt bee microbiota. This review explores recent research on the effects of glyphosate and its formulations on the gut microbiota of honeybees and bumblebees. It examines species-specific responses, methodological approaches, and broader ecological implications. While evidence indicates that glyphosate can alter the gut microbiome in some bee species, its effects vary depending on exposure conditions, species, and the composition of microbial communities. Additionally, glyphosate formulations containing surfactants may exacerbate these effects. Given the endocrine-disrupting properties of glyphosate, further research is needed to understand the long-term consequences of exposure, especially its impact on hormonal regulation and bee resilience to environmental stressors. Full article

(This article belongs to the Special Issue Environmental Contaminant Exposure and Intake from Agricultural Products)

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14 pages, 1622 KiB

Open AccessArticle

Neonicotinoid Residues in Tea Products from China: Contamination Patterns and Implications for Human Exposure

by Yulong Fan, Hongwei Jin, Jinru Chen, Kai Lin, Lihua Zhu, Yijia Guo, Jiajia Ji and Xiaming Chen

Toxics 2025, 13(7), 550; https://doi.org/10.3390/toxics13070550 - 29 Jun 2025

Abstract

Neonicotinoids (NEOs) are a class of systemic insecticides widely used in agriculture owing to their high efficacy and selectivity. As one of the most globally consumed beverages, tea may represent a potential dietary source of pesticide residues. However, limited research has examined NEO [...] Read more.

Neonicotinoids (NEOs) are a class of systemic insecticides widely used in agriculture owing to their high efficacy and selectivity. As one of the most globally consumed beverages, tea may represent a potential dietary source of pesticide residues. However, limited research has examined NEO contamination in tea and its implications for human exposure, highlighting the need for further investigation. Therefore, this study comprehensively evaluated the residue characteristics, processing effects, and human exposure risks of six NEOs—dinotefuran (DIN), imidacloprid (IMI), acetamiprid (ACE), thiamethoxam (THM), clothianidin (CLO), and thiacloprid (THI)—in Chinese tea products. According to the findings, the primary pollutants, ACE, DIN, and IMI, accounted for 95.65% of the total NEO residues in 137 tea samples, including green, oolong, white, black, dark, and herbal teas. The highest total target NEO (∑₆NEOs) residue level was detected in oolong tea (mean: 57.86 ng/g). Meanwhile, IMI exhibited the highest residue level (78.88 ng/g) in herbal tea due to the absence of high-temperature fixation procedures. Concentrations of DIN in 61 samples (44.5%) exceeded the European Union’s maximum residue limit of 10 ng/g. Health risk assessment indicated that both the chronic hazard quotient (cHQ) and acute hazard quotient (aHQ) for adults and children were below the safety threshold (<1). However, children required special attention, as their exposure risk was 1.28 times higher than that of adults. The distribution of NEO residues was significantly influenced by tea processing techniques, such as full fermentation in black tea. Optimizing processing methods (e.g., using infrared enzyme deactivation) and implementing targeted pesticide application strategies may help mitigate risk. These results provide a scientific foundation for enhancing tea safety regulations and protecting consumer health. Full article

(This article belongs to the Special Issue Human Biomonitoring in Health Risk Assessment of Emerging Chemicals)

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14 pages, 529 KiB

Open AccessArticle

Emerging Pollutants in Chinstrap Penguins and Krill from Deception Island (South Shetland Islands, Antarctica)

by Miguel Motas, Silvia Jerez-Rodríguez, José Manuel Veiga-del-Baño, Juan José Ramos, José Oliva, Miguel Ángel Cámara, Pedro Andreo-Martínez and Simonetta Corsolini

Toxics 2025, 13(7), 549; https://doi.org/10.3390/toxics13070549 - 29 Jun 2025

Abstract

This study aimed to evaluate the presence of emerging pollutants [perfluorinated compounds, phthalates and bisphenol A (BPA)] in chinstrap penguins (Pygoscelis antarctica) and krill (Euphausia superba) from Deception Island (South Shetland Islands, Antarctica) to provide data on the occurrence [...] Read more.

This study aimed to evaluate the presence of emerging pollutants [perfluorinated compounds, phthalates and bisphenol A (BPA)] in chinstrap penguins (Pygoscelis antarctica) and krill (Euphausia superba) from Deception Island (South Shetland Islands, Antarctica) to provide data on the occurrence of emerging pollutants in Antarctica. For this purpose, thirty-four samples were studied, including four samples of adult tissue and six samples of chick tissue, as well as krill samples from the area. The selected samples were subjected to extraction processes and subsequent analytical determination of perfluorooctane sulfonate, perfluorooctanoic acid, di(2-ethylhexyl) phthalate, mono(2-ethylhexyl) phthalate and BPA using high-performance liquid chromatography coupled with electrospray ionization mass spectrometry. Our results highlight that the analyzed organic pollutants, except for BPA, are clearly present in Pygoscelis antarctica and Euphausia superba from Deception Island. Full article

(This article belongs to the Special Issue Environmental Toxicology and Risk Assessment of Priority Substances)

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28 pages, 5675 KiB

Open AccessArticle

Comparison of Heavy Metal Pollution, Health Risk, and Sources Between Surface and Deep Layers for an Agricultural Region Within the Pearl River Delta: Implications for Soil Environmental Research

by Zhenwei Bi, Yu Guo, Zhao Wang, Zhaoyu Zhu, Mingkun Li and Tingping Ouyang

Toxics 2025, 13(7), 548; https://doi.org/10.3390/toxics13070548 - 29 Jun 2025

Abstract

During the past decades, agricultural soil heavy metal pollution has been becoming increasingly severe due to urbanization and industrialization. However, the impact of externally input heavy metals on deep soils remains unclear because most previous relevant research only focused on surface soils. In [...] Read more.

During the past decades, agricultural soil heavy metal pollution has been becoming increasingly severe due to urbanization and industrialization. However, the impact of externally input heavy metals on deep soils remains unclear because most previous relevant research only focused on surface soils. In the present study, Concentrations of eight heavy metals (Cu, Zn, Ni, Pb, Cr, Cd, As, and Hg) were determined for 72 pairs of surface and deep soil samples collected from an agricultural region close to the Pearl River estuary. Subsequently, heavy metal pollution and potential health risks were assessed using the Geo-accumulation Index and Potential Ecological Risk Index, a dose response model and Monte Carlo simulation, respectively. Principal component analysis (PCA) and the positive matrix factorization (PMF) receptor model were combined to analyze heavy metal sources. The results indicated that average concentrations of all heavy metals exceeded their corresponding background values. Cd was identified as the main pollutant due to its extremely high values of I_geo and Er. Unacceptable potential heavy metal non-carcinogenic and carcinogenic risks indicated by respectively calculated HI and TCR, higher than thresholds 1.0 and 1.0 × 10⁻⁴, mainly arose from heavy metals As, Cd, Cr, and Ni through food ingestion and dermal absorption. Anthropogenic sources respectively contributed 19.7% and 38.9% for soil As and accounted for the main contributions to Cd, Cu, and Hg (Surface: 90.2%, 65.4%, 67.3%; Deep: 53.8%, 54.6%, 56.2%) within surface and deep layers. These results indicate that soil heavy metal contents with deep layers were also significantly influenced by anthropogenic input. Therefore, we suggest that both surface and deep soils should be investigated simultaneously to gain relatively accurate results for soil heavy metal pollution and source apportionments. Full article

(This article belongs to the Section Human Toxicology and Epidemiology)

24 pages, 4413 KiB

Open AccessArticle

Trace Elements in Indoor Dust Exposure from Child Development Centers and Health Risk Assessment in Haze and Industrial Areas, Thailand

by Susira Bootdee, Sopittaporn Sillapapiromsuk and Sawaeng Kawichai

Toxics 2025, 13(7), 547; https://doi.org/10.3390/toxics13070547 - 29 Jun 2025

Abstract

This study aimed to examine trace element concentrations in indoor dust and evaluate health risks in child development centers in haze and industrial areas of Thailand from November 2023 to April 2024. The samples were extracted using a microwave oven and analyzed via [...] Read more.

This study aimed to examine trace element concentrations in indoor dust and evaluate health risks in child development centers in haze and industrial areas of Thailand from November 2023 to April 2024. The samples were extracted using a microwave oven and analyzed via ICP-OES. The finding indicated that the levels of As, Cr, Pb, V, Fe, Mn, and Zn in the dust from child development centers in the industrial area were significantly higher than those in the haze area (p < 0.05). The presence of trace element contaminants in indoor dust is indicative of anthropogenic sources. Cd and Zn in both areas have shown significantly elevated risks, according to the probable ecological risk factor. Source apportionment identified traffic, road dust, and biomass combustion as the principal sources of pollution in the haze area, while traffic and combustion activities were significant in the industrial area. Non-carcinogenic risk assessments for children exposed to As, Pb, Cu, and Cr revealed potential health risks (HI > 1). Furthermore, the total cancer risk (TCR) linked to As, Cr, and Ni is considered acceptable within the criteria of 10⁻⁶ to 10⁻⁴. However, long-term exposure may increase the risk of cancer in children. Full article

(This article belongs to the Special Issue Occupational Exposure to Heavy Metals in Environmentally Vulnerable Areas)

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17 pages, 626 KiB

Open AccessArticle

Exposure to Environmental Chemicals from Environmental Tobacco Smoking in Korean Adolescents

by Jung-Eum Lee, Ah-Reum Jo, Sunho Lee and Wanhyung Lee

Toxics 2025, 13(7), 546; https://doi.org/10.3390/toxics13070546 - 29 Jun 2025

Abstract

Background: Environmental tobacco smoke (ETS) exposes adolescents to various environmental toxins, potentially affecting their developmental health. However, limited research exists on the associations between ETS exposure and the bodily burdens of environmental chemicals on adolescents. This study aimed to investigate the relationship between [...] Read more.

Background: Environmental tobacco smoke (ETS) exposes adolescents to various environmental toxins, potentially affecting their developmental health. However, limited research exists on the associations between ETS exposure and the bodily burdens of environmental chemicals on adolescents. This study aimed to investigate the relationship between ETS exposure and the concentration of various environmental chemicals in adolescents, utilizing urinary cotinine as an objective biomarker. Methods: Data from 828 adolescents aged 12–17 years participating in the Korean National Environmental Health Survey (KoNEHS) were analyzed. ETS exposure was assessed via self-reported questionnaires and confirmed by urinary cotinine measurements. Levels of 33 environmental chemicals, including heavy metals, polycyclic aromatic hydrocarbons (PAHs), phthalates, phenols, volatile organic compounds (VOCs), and per- and polyfluoroalkyl substances (PFASs), were measured. Statistical analyses were conducted after adjusting for covariates. Results: Adolescents exposed to ETS showed significantly higher urinary cotinine and mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP) concentrations than non-exposed adolescents. Additionally, significant positive correlations were observed between urinary cotinine levels and metabolites of PAHs (NAP, OHFlu), phenols (BPA, BPS), phthalates (MMP), and VOCs (t,t-MA) after adjustments. However, ETS exposure was not significantly associated with heavy metal concentrations. Conclusions: This study described the association between ETS exposure and environmental chemicals. A trend has been identified between ETS exposure in adolescents and increased bodily concentrations of various environmental chemicals, including PAHs, phenols, phthalates, and VOCs. As adolescence is a critical developmental period of vulnerability to environmental toxins, reducing ETS exposure to protect adolescents’ health and prevent potential lifelong health effects should be emphasized. This study was based on a cross-sectional design, and some confounding factors and measurement limitations may exist. Therefore, caution is needed in interpreting causality, and further research is recommended to determine more precise causality and long-term health effects. Full article

(This article belongs to the Section Human Toxicology and Epidemiology)

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29 pages, 1903 KiB

Open AccessArticle

PhotoChem Reference Chemical Database for the Development of New Alternative Photosafety Test Methods

by Ga-Young Lee, Jee-Hyun Hwang, Jeong-Hyun Hong, Seungjin Bae and Kyung-Min Lim

Toxics 2025, 13(7), 545; https://doi.org/10.3390/toxics13070545 - 28 Jun 2025

Abstract

Photosafety assessments are a key requirement for the safe development of pharmaceuticals, cosmetics, and agrochemicals. Although in vitro methods are widely used for phototoxicity and photoallergy testing, their limited applicability and predictive power often necessitate supplemental in vivo studies. To address this, we [...] Read more.

Photosafety assessments are a key requirement for the safe development of pharmaceuticals, cosmetics, and agrochemicals. Although in vitro methods are widely used for phototoxicity and photoallergy testing, their limited applicability and predictive power often necessitate supplemental in vivo studies. To address this, we developed the PhotoChem Reference Chemical Database, comprising 251 reference compounds with curated data from in vitro, in vivo, and human studies. Using this database, we evaluated the predictive capacity of three OECD in vitro test guidelines—TG 432 (3T3 NRU), TG 495 (ROS assay), and TG 498 (reconstructed human epidermis)—by comparing the results against human and animal data. Against human reference data, all three test methods showed high sensitivity (≥82.6%) and strong overall accuracy: TG 432 (accuracy: 94.2% (49/52)), TG 495 (100% (27/27)), and TG 498 (86.7% (26/30)). In comparison with animal data, sensitivity remained high for all tests (≥92.0%), while specificity varied: TG 432 (54.3% (19/35)), TG 495 (63.6% (7/11)), and TG 498 (90.5% (19/21)). TG 498 demonstrated the most balanced performance in both sensitivity and specificity across datasets. We also analyzed 106 drug approvals from major regulatory agencies to assess real-world application of photosafety testing. Since the mid-2000s, the use of in vitro phototoxicity assays has steadily increased in Korea, particularly following the 2021 revision of the MFDS regulations. Test method preferences varied by region, with 3T3 NRU and ROS assays most widely used to evaluate phototoxicity, while photo-LLNA and guinea pig tests were frequently employed for photoallergy assay. Collectively, this study provides a valuable reference for optimizing test method selection and supports the broader adoption of validated, human-relevant non-animal photosafety assessment strategies. Full article

(This article belongs to the Special Issue New Approach Methodologies for Agrochemicals and Food Toxicology)

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16 pages, 1542 KiB

Open AccessArticle

Exposure to 6-PPD Quinone Disrupts Adsorption and Catabolism of Leucine and Causes Mitochondrial Dysfunction in Caenorhabditis elegans

by Wei Wang, Yunhui Li and Dayong Wang

Toxics 2025, 13(7), 544; https://doi.org/10.3390/toxics13070544 - 28 Jun 2025

Abstract

6-PPD quinone (6-PPDQ) is a derivative from 6-PPD, an antioxidant added in tires. Leucine is an important amino acid that needs to be obtained from the diet. In Caenorhabditis elegans, we examined the effect of 6-PPDQ exposure at environmentally relevant concentrations (ERCs) [...] Read more.

6-PPD quinone (6-PPDQ) is a derivative from 6-PPD, an antioxidant added in tires. Leucine is an important amino acid that needs to be obtained from the diet. In Caenorhabditis elegans, we examined the effect of 6-PPDQ exposure at environmentally relevant concentrations (ERCs) on the content of leucine and underlying mechanisms. In nematodes, 0.1–10 μg/L of 6-PPDQ decreased leucine content. The expression of the aat-1-encoding amino acid transmembrane transporter was decreased by 0.1–10 μg/L of 6-PPDQ, and leucine content was reduced by aat-1 RNAi. Meanwhile, the expression of bcat-1-encoding branched-chain amino acid transferase was increased by 0.1–10 μg/L of 6-PPDQ, and leucine content was increased by bcat-1 RNAi. Additionally, the expressions of dbt-1 and ivd-1 encoding two enzyme genes governing NADH and FADH₂ generations were decreased by 0.1–10 μg/L of 6-PPDQ, and their expressions in 6-PPDQ exposed nematodes were increased by bcat-1 RNAi. After 6-PPDQ exposure, NADH content was reduced by dbt-1 RNAi, and FADH₂ content was reduced by ivd-1 RNAi. Moreover, 6-PPDQ-induced mitochondrial dysfunction and other aspects of toxicity (such as intestinal ROS generation and lipofuscin accumulation, inhibited locomotion, and reduced brood size) were suppressed by bcat-1 RNAi and strengthened by dbt-1 and ivd-1 RNAi. The 6-PPDQ-induced toxicity and the decrease in dbt-1 and ivd-1 expressions could be inhibited by following leucine (5 mM) treatment. Our results demonstrate the important association of leucine adsorption and catabolism with 6-PPDQ toxicity induction. Full article

(This article belongs to the Section Human Toxicology and Epidemiology)

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