Toxics

19 pages, 990 KB

Open AccessArticle

Temporal Variability of Urinary Organophosphate Flame Retardant Metabolites Among E-Waste Workers in France: A Pilot Study to Inform Occupational Biomonitoring Sampling Design

by Baninia Habchi, Guillaume Antoine, Aurélie Martin Remy, François Zimmermann, Marie-Thérèse Lecler, Williams Esteve, Claude Emond, Nathalie Grova and Sophie Ndaw

Toxics 2026, 14(9), 778; https://doi.org/10.3390/toxics14090778 - 31 Aug 2026

Abstract

Workers in the e-waste industry are exposed to chemical hazards, including organophosphate esters (OPEs) used as flame retardants (FRs). Assessing exposure through spot urine metabolite analysis is challenging due to limited knowledge of the toxicokinetics and urinary excretion patterns of OPEs. This pilot [...] Read more.

Workers in the e-waste industry are exposed to chemical hazards, including organophosphate esters (OPEs) used as flame retardants (FRs). Assessing exposure through spot urine metabolite analysis is challenging due to limited knowledge of the toxicokinetics and urinary excretion patterns of OPEs. This pilot study investigates the temporal variability of seven organophosphate flame retardants (OPFRs) in urine samples from e-waste workers over five workdays to identify the most representative spot urine sample for accurately assessing occupational exposure. Six exposed workers provided urine samples from the first shift of the working week to the morning after the last workday. Seven metabolites, (bis(2-chloroethyl) phosphate (BCEP), diphenyl phosphate (DPHP), di-o-cresyl phosphate (DoCP), di-m-cresyl phosphate (DmCP), di-p-cresyl phosphate (DpCP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP) and bis-(1-chloro-2-propyl) phosphate (BCPP)), were analyzed using liquid chromatography-mass spectrometry. DmCP + DpCP showed weekly increases and fair to good intraclass correlation coefficient (ICC), indicating moderate temporal variability across days. Conversely, DPHP and BCEP showed rapid decreases and lower ICC, suggesting higher intra-day variability. A grouping approach based on collection time and workday showed that the suitable spot urine is 2–5 h delayed post-shift for BCEP and DPHP, whereas the end of the workweek is the most appropriate time for DmCP + DpCP. This pilot study provides preliminary information on temporal variability to inform sampling design. This approach could be extended to a broader range of FRs, thereby enhancing the efficiency and accuracy of occupational biomonitoring. Full article

(This article belongs to the Special Issue Human Exposure and Health Risk Assessment of Emerging Contaminants)

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16 pages, 1483 KB

Open AccessPerspective

Accelerating Cosmetic Innovation Through Next-Generation Computational Toxicology: From Structural Alerts to Molecular Dynamics and Artificial Intelligence for Skin Sensitization Assessment

by Thomas Enrique Quintero-Trujillo, Liseth Diaz-Rojas, Helen Andrade and Paola Alfonso-Romero

Toxics 2026, 14(9), 777; https://doi.org/10.3390/toxics14090777 - 31 Aug 2026

Abstract

Skin sensitization remains a critical toxicological endpoint in cosmetic ingredient development, particularly under accelerated innovation cycles and increasingly stringent safety requirements. Although NAMs have achieved substantial regulatory maturity for this endpoint, most computational approaches—including structural alerts, read-across, and quantitative structure–activity relationship models—rely predominantly [...] Read more.

Skin sensitization remains a critical toxicological endpoint in cosmetic ingredient development, particularly under accelerated innovation cycles and increasingly stringent safety requirements. Although NAMs have achieved substantial regulatory maturity for this endpoint, most computational approaches—including structural alerts, read-across, and quantitative structure–activity relationship models—rely predominantly on chemical structure and statistical associations, with limited representation of the molecular processes underlying sensitization. This perspective proposes a transparent and testable computational framework that integrates conventional chemical descriptors, reaction-domain information, covalent docking, molecular dynamics simulations, and machine learning methods. The framework is organized around the skin sensitization adverse outcome pathway and focuses on generating mechanistically informed descriptors associated with the molecular initiating event and selected molecular processes related to keratinocyte activation. These descriptors include reactive geometry, residue accessibility, interaction persistence, conformational behavior, and perturbation hypotheses involving the KEAP1–NRF2 regulatory axis. Rather than replacing established experimental NAMs or DAs, the proposed workflow is intended as a complementary, tiered evidence layer for the early prioritization of structurally characterized cosmetic ingredients and for guiding subsequent experimental testing. Its future value will depend on module-level validation, demonstration of incremental predictive performance, explicit applicability-domain and uncertainty assessment, computational scalability, and prospective comparison with established NAM outcomes. Full article

(This article belongs to the Special Issue Applicability of New Approach Methodologies (NAMs) to Skin Sensitization: Insights from Industry and Regulatory Perspectives)

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16 pages, 5418 KB

Open AccessArticle

Unveiling the Molecular Mechanisms of Bisphenol-Induced Olfactory Toxicity in Zebrafish

by Yaxuan Li, Jing Cao, Haoliang Jiang, Mei Hou, Xuefeng Hu, Liting Chen, Dan Li and Yongju Luo

Toxics 2026, 14(9), 776; https://doi.org/10.3390/toxics14090776 - 31 Aug 2026

Abstract

Bisphenol analogues, including bisphenol F (BPF) and bisphenol S (BPS), are increasingly used as alternatives to bisphenol A (BPA), yet their potential olfactory effects remain poorly understood. In this study, adult zebrafish (Danio rerio) were exposed to environmentally relevant concentrations (5 [...] Read more.

Bisphenol analogues, including bisphenol F (BPF) and bisphenol S (BPS), are increasingly used as alternatives to bisphenol A (BPA), yet their potential olfactory effects remain poorly understood. In this study, adult zebrafish (Danio rerio) were exposed to environmentally relevant concentrations (5 μg/L) of BPF and BPS for 28 days to investigate their impacts on the olfactory system. Histopathological assessment revealed changes in olfactory epithelial morphology, particularly in the BPF-exposed group. Transcriptomic analysis identified 3260 and 1602 differentially expressed genes in BPF and BPS exposure groups, respectively, involving pathways related to signal transduction, immune response, endocrine regulation, cell apoptosis, and olfactory signaling. Further molecular docking and 200 ns molecular dynamics simulations demonstrated stable interactions between with BPF exhibiting stronger binding affinities and more hydrophobic contacts with the targeted proteins (OR, GNB2 and p53) among the targeted proteins. Binding free energy calculations confirmed BPF’s greater binding potential. These findings suggest that BPF may exert more potent olfactory toxicity than BPS, disrupting signal transmission and sensory function in aquatic species. This study provides new mechanistic insights into the molecular basis of bisphenol-induced olfactory disruption and emphasizes the ecological risks of BPF and BPS in aquatic environments. Full article

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18 pages, 9524 KB

Open AccessArticle

Impacts of Wastewater Treatment Processes on the Occurrence Characteristics of Microplastics—Taking Four Wastewater Treatment Plants in Northern Henan Province as Examples

by Yiping Guo, Jinhong Li, Shihang Ni, Qianqian Zhang, Li Guo, Bingtao Liu, Peng Liu, Weigao Zhao, Yupeng Li and Hanzhong Jia

Toxics 2026, 14(9), 775; https://doi.org/10.3390/toxics14090775 - 31 Aug 2026

Abstract

As emerging persistent contaminants, microplastics (MPs) are ubiquitous in aquatic environments. Wastewater treatment plants (WWTPs) act as critical sinks and sources of MPs, and their MPs removal efficiency can strongly influence aquatic ecological safety. To investigate how different process configurations affect MPs occurrence [...] Read more.

As emerging persistent contaminants, microplastics (MPs) are ubiquitous in aquatic environments. Wastewater treatment plants (WWTPs) act as critical sinks and sources of MPs, and their MPs removal efficiency can strongly influence aquatic ecological safety. To investigate how different process configurations affect MPs occurrence and removal performance, four municipal WWTPs equipped with diverse biological and advanced treatment processes were sampled and analyzed. MPs were extracted via density flotation combined with H₂O₂ digestion, and their morphological and polymeric features were identified using stereomicroscopy and Fourier-transform infrared (FTIR) spectroscopy. The results revealed that MPs removal efficiencies differed significantly across treatment processes: WWTP4 exhibited the highest comprehensive removal efficiency of 63.89% in the operational situations, followed by WWTP1 of 56.25% and WWTP3 of 51.61%, while WWTP2 exhibited the weakest elimination capacity of 28.12%. It could also be concluded that the differences were primarily governed by biological adsorption and advanced filtration units. Meanwhile, Fragmented and pellet MPs showed higher removal efficiencies than fibrous and film-shaped MPs, while Polymers including PVC, PS, PTFE and PP were more resistant to removal. Longer hydraulic retention time (HRT) and a stable and sufficiently long sludge retention time (SRT) promoted the association of MPs with activated sludge, whereas excessive aeration induced MPs fragmentation and resuspension. Optimizing operational parameters and upgrading advanced filtration facilities could facilitate the regulation and management of MPs. This study provides a theoretical basis for mitigating MPs emissions from municipal WWTPs. Full article

(This article belongs to the Section Emerging Contaminants)

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36 pages, 1517 KB

Open AccessReview

Chemical Food Safety of Edible Insects in the European Union: Current Evidence and Regulatory Blind Spots

by Zsuzsa Farkas, Theodora Bernitsa, Maria do Céu Costa and József Lehel

Toxics 2026, 14(9), 774; https://doi.org/10.3390/toxics14090774 - 31 Aug 2026

Abstract

Edible insects are increasingly promoted as alternative foods, but their chemical safety is difficult to assess because hazards may arise throughout the production chain and the regulatory framework remains incomplete. This structured narrative review synthesises current evidence on chemical hazards in edible insects [...] Read more.

Edible insects are increasingly promoted as alternative foods, but their chemical safety is difficult to assess because hazards may arise throughout the production chain and the regulatory framework remains incomplete. This structured narrative review synthesises current evidence on chemical hazards in edible insects and examines their interpretation within the European Union regulatory framework. The available literature indicates that rearing substrates and production environments are major sources of contamination, particularly for heavy metals, mycotoxins, pesticide residues, veterinary medicinal product residues, and persistent or emerging contaminants. However, transfer into insect biomass is highly species-, life-stage-, and compound-dependent, and metabolism, excretion, or transformation may reduce parent-compound concentrations without eliminating uncertainty regarding metabolites and other transformation products. Processing and storage may further modify the chemical profile through the formation of acrylamide, furan derivatives, lipid-oxidation products, and biogenic amines. Although the EU novel food framework provides product-specific premarket assessment, representative market-occurrence and consumption data remain limited, and generally applicable insect-specific maximum levels for contaminants have not been established, whereas pesticide residues are governed by the horizontal EU MRL framework. Chemical safety assessment should therefore adopt a full-chain, species- and product-specific approach integrating substrate control, contaminant fate, processing, storage, and consumer exposure. Full article

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18 pages, 1932 KB

Open AccessArticle

Chemical Regimes and PMF-Resolved Sources Linked to Acute PM₁₀ Ecotoxicity in Luanda, Angola

by Alan Victor da Silva, Estela D. Vicente, Ana M. Sánchez de la Campa, Yago Cipoli, Diogo N. Cardoso, Susana Loureiro, Anabela Leitão, Manuel Feliciano and Célia Alves

Toxics 2026, 14(9), 773; https://doi.org/10.3390/toxics14090773 - 30 Aug 2026

Abstract

In rapidly expanding African cities, the ecotoxicological relevance of PM₁₀ remains largely unresolved, especially where particle mass, chemical composition and emission sources are rarely assessed together. Here, 116 daily PM₁₀ samples collected in Luanda between 27 June and 5 November 2023 [...] Read more.

In rapidly expanding African cities, the ecotoxicological relevance of PM₁₀ remains largely unresolved, especially where particle mass, chemical composition and emission sources are rarely assessed together. Here, 116 daily PM₁₀ samples collected in Luanda between 27 June and 5 November 2023 were tested using the Microtox^® Aliivibrio fischeri assay on aqueous extracts. Chemical speciation was combined with centred log-ratio (CLR) compositional clustering to identify recurring chemical regimes, while Positive Matrix Factorisation (PMF) was used to resolve the corresponding emission sources. Toxicity was moderate but highly variable: Toxic units after 15 min (TU₁₅) ranged from 0.84 to 8.54, with changes in toxicity units between 5 and 15 min (ΔTU) varying from −1.51 to +4.84. Only 3 of the 116 samples showed TU₁₅ < 1, and none reached TU₁₅ ≥ 10. The strongest responses occurred under a metal-enriched chemical regime (C2), characterised by elevated Zn, Pb and Cd concentrations, which showed the highest mean TU₁₅ (4.22) and ΔTU (1.52). This regime coincided with PMF evidence identifying non-ferrous metallurgy plus galvanised/metal scrap handling and burning as the factor most strongly associated with toxicity (ρTU₁₅ = 0.63; ρΔTU = 0.78), followed by a Ni-rich metallurgical factor with possible aviation influence (ρTU₁₅ = 0.51). Conversely, a marine/ionic chemical regime (C3) showed lower, stable toxicity, consistent with negative marine aerosol associations. These findings show that integrating chemical regimes with PMF-resolved sources identifies metal-related emissions as the main drivers of PM₁₀ ecotoxicity. Full article

(This article belongs to the Topic Air Quality and the Built Environment, 2nd Edition)

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35 pages, 1755 KB

Open AccessReview

Heavy Metal-Induced Retinal Injury in Zebrafish (Danio rerio): Histopathological Alterations, Molecular Mechanisms and Regenerative Responses

by Alina Iliuța Olărița, Alexandra Szilagyi, Alexandra Jităreanu, Gheorghe Solcan and Carmen Solcan

Toxics 2026, 14(9), 772; https://doi.org/10.3390/toxics14090772 - 30 Aug 2026

Abstract

Heavy metal contamination is a significant environmental risk factor for ocular dysfunction and retinal degeneration in both aquatic organisms and humans. Zebrafish (Danio rerio) have become an important vertebrate model for retinal toxicology research due to their conserved retinal architecture, cone-rich [...] Read more.

Heavy metal contamination is a significant environmental risk factor for ocular dysfunction and retinal degeneration in both aquatic organisms and humans. Zebrafish (Danio rerio) have become an important vertebrate model for retinal toxicology research due to their conserved retinal architecture, cone-rich visual system, optical transparency during development, and remarkable capacity for retinal regeneration. This narrative review synthesizes current evidence on the effects of heavy metals on the development, structure, function, and regenerative responses of the zebrafish visual system, with particular focus on retinal alterations, molecular mechanisms, and visual impairment. Studies indicate that exposure to cadmium, lead, arsenic, chromium, copper, mercury, and metal mixtures results in retinal disorganization, photoreceptor degeneration, vacuolization, retinal pigment epithelium damage, impaired retinogenesis, and alterations in visually mediated behaviors. Mechanistic investigations reveal that heavy metal-induced retinal toxicity involves oxidative stress, mitochondrial dysfunction, endoplasmic reticulum stress, apoptosis, neuroinflammation, DNA damage, and dysregulation of genes critical for retinal development and photoreceptor maintenance. Functional assays, such as the optomotor response and optokinetic reflex, provide sensitive endpoints for detecting visual dysfunction that may precede overt structural degeneration. Furthermore, the unique regenerative capacity of the zebrafish retina, primarily mediated by Müller glia reprogramming, provides valuable opportunities to study endogenous retinal repair following toxic injury. Overall, current evidence establishes zebrafish as a versatile and translationally relevant model for investigating heavy metal-induced retinal injury, visual dysfunction, and regenerative responses. Future research that incorporates environmentally relevant exposure paradigms, mixture toxicology, multi-omics approaches, and regenerative signaling pathways is likely to enhance understanding of metal-associated retinal disease and support the development of novel therapeutic strategies for retinal degeneration and vision loss. Full article

(This article belongs to the Special Issue Toxicity and Mechanisms of Exposure to Metals and Metalloids)

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19 pages, 1759 KB

Open AccessArticle

The Impact of Polycyclic Aromatic Hydrocarbons Exposure from Seasonal Biomass Burning on Oxidative Stress and Genotoxicity Biomarkers in Patients with Diabetes and Hypertension in Chiang Mai, Thailand

by Muhammad Ali, Xianfeng Cao, Udomsap Jaitham, Peerapong Jeeno, Anurak Wongta, Saweang Kawichai, Sumed Yadoung and Surat Hongsibsong

Toxics 2026, 14(9), 771; https://doi.org/10.3390/toxics14090771 - 29 Aug 2026

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are produced primarily by incomplete combustion of organic materials, including biomass burning, vehicle exhaust, and forest fires. Exposure to PAHs can induce reactive oxygen species (ROS) and oxidative stress, leading to lipid peroxidation and DNA damage. Biomass burning is [...] Read more.

Polycyclic aromatic hydrocarbons (PAHs) are produced primarily by incomplete combustion of organic materials, including biomass burning, vehicle exhaust, and forest fires. Exposure to PAHs can induce reactive oxygen species (ROS) and oxidative stress, leading to lipid peroxidation and DNA damage. Biomass burning is a major environmental and public health problem in Chiang Mai province, containing particulate matter linked with respiratory and cardiovascular diseases. This prospective observational study aimed to evaluate the association between oxidative stress biomarkers and PAH exposure. A total of 152 participants comprised healthy controls (88), diabetes patients (35), hypertension patients (15) and diabetes + hypertension patients (14). Only participants aged more than 18 years were included. Participants who had acute respiratory infection or malignancies were excluded. This study was conducted in the pre-burning (December) and post-burning (May) periods by measuring biomarkers such as 1-OHP, MDA and 8-OHdG. Urinary 1-OHP increased significantly in the post-burning period from 0.21 ± 0.50 to 0.87 ± 1.25 μmol/mol creatinine (p < 0.001). Serum 8-OHdG increased significantly in all participants from 51.04 ± 24.90 to 66.08 ± 27.82 pg/mL (p < 0.001) and increased significantly in the diabetic and hypertension group. Serum MDA did not show any significant change post-burning (6.09 ± 3.71 to 6.00 ± 3.71 nmol/mL; p = 0.825), but MDA significantly decreased in the diabetic group (p = 0.017). 8-OHdG tended to increase in all clinical groups in the post-burning season compared to the pre-burning season, indicating oxidative DNA damage. 8-OHdG was found to be a sensitive biomarker of oxidative stress, suggesting its potential as an early indicator in haze season in vulnerable populations. Full article

(This article belongs to the Special Issue Air Pollutants: Sources, Characteristics, Environmental Impacts and Human Health Risks)

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16 pages, 4677 KB

Open AccessArticle

The Combined Effects of Citric Acid and Ammonium Nitrate on the Phytoremediation of Cd-Phenanthrene Co-Contaminated Soil Using Marigold

by Xinzhuo Qian, Ting Xu, Xuemei Zhong, Weijin Zheng, Lizhu Yuan and Bo Song

Toxics 2026, 14(9), 770; https://doi.org/10.3390/toxics14090770 - 28 Aug 2026

Abstract

Citric acid (CA) and nitrogen (N) fertilizers have been widely applied to enhance phytoremediation of various contaminated soils, yet their combined effects and underlying mechanisms in cadmium (Cd)–polycyclic aromatic hydrocarbon (PAH) co-contaminated systems remain poorly understood. Here, we investigated the combined effects of [...] Read more.

Citric acid (CA) and nitrogen (N) fertilizers have been widely applied to enhance phytoremediation of various contaminated soils, yet their combined effects and underlying mechanisms in cadmium (Cd)–polycyclic aromatic hydrocarbon (PAH) co-contaminated systems remain poorly understood. Here, we investigated the combined effects of CA and ammonium nitrate on the phytoremediation of Cd–phenanthrene (Phe) co-contaminated soil using marigold (Tagetes patula L.), with random forest, mantel tests, and structural equation modeling employed to explore hypothesized pathways and associations. The results demonstrated that combined CA and N application significantly promoted plant growth, Cd uptake, and Phe dissipation. Among the tested treatments, the low-dose combination (1 g CA + 0.1 g N pot⁻¹) increased plant biomass by 88%, enhanced shoot Cd uptake by 121%, and achieved a Phe dissipation rate of 76.56%, representing the optimal remediation strategy. Mechanistically, the synergy between CA and N extends beyond simple growth promotion—N drives biomass production and, independently, facilitates Cd mobilization through rhizosphere acidification, while CA enhances contaminant bioavailability and buffers N-induced salt stress, together maintaining rhizosphere ionic homeostasis for efficient Cd translocation and Phe dissipation. This study provides a mechanistic framework for designing combined amendment strategies to enhance phytoremediation of co-contaminated soils. Full article

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16 pages, 2042 KB

Open AccessArticle

Mercury in Red Knots (Calidris canutus rufa): Inter-Annual and Geographic Variation in Blood Mercury and Associated Toxicological Risk Along the Atlantic Flyway

by Stephanie Feigin and Joanna Burger

Toxics 2026, 14(9), 769; https://doi.org/10.3390/toxics14090769 - 28 Aug 2026

Abstract

Shorebird populations are declining sharply, and trace metal contaminants may compound the many migration-related threats they face by affecting feeding, migration, and reproductive success. Despite this risk to the federally threatened Red Knot (Calidris canutus rufa), blood mercury in Red Knots [...] Read more.

Shorebird populations are declining sharply, and trace metal contaminants may compound the many migration-related threats they face by affecting feeding, migration, and reproductive success. Despite this risk to the federally threatened Red Knot (Calidris canutus rufa), blood mercury in Red Knots has not been examined outside Delaware Bay, and the associated toxicological risk has not been assessed across the annual cycle. We report blood mercury from four cohorts: spring 2024 and spring 2025 at Delaware Bay, fall 2024 at Avalon, New Jersey, and spring 2025 at Kiawah Island, South Carolina. Blood mercury was substantially higher in 2024 than in 2025 across both cohorts. In 2024, 38% of spring Delaware Bay birds and 62% of fall Avalon birds exceeded the 200 ng/g adverse sublethal risk threshold; no birds sampled in 2025 exceeded this level. No biological endpoints were measured, so this risk is inferred from published thresholds. Within single-day Delaware Bay flocks, body mass and mercury were positively related, an association consistent with bioaccumulation. Two cohorts had small samples, and site, season, and migratory stage are confounded in the design. Risk varies markedly among years, and a single sampling event is unlikely to characterize mercury exposure or its associated risk. Full article

(This article belongs to the Section Ecotoxicology)

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15 pages, 534 KB

Open AccessArticle

Hair Metal Concentrations in Adults Living in Campania, Italy: A Cross-Sectional Biomonitoring Study in a Mixed Geogenic–Anthropogenic Exposure Setting

by Rossella Farina, Juri Rimauro, Silvio Del Pizzo, Angelo Riccio and Elena Chianese

Toxics 2026, 14(9), 768; https://doi.org/10.3390/toxics14090768 - 27 Aug 2026

Abstract

Human biomonitoring in environmentally complex regions requires not only matrices that are easy to collect but also careful consideration of external contamination, non-detects, and analytical uncertainty. Inductively coupled plasma mass spectrometry (ICP–MS) was used to measure the concentrations of 24 elements in occipital [...] Read more.

Human biomonitoring in environmentally complex regions requires not only matrices that are easy to collect but also careful consideration of external contamination, non-detects, and analytical uncertainty. Inductively coupled plasma mass spectrometry (ICP–MS) was used to measure the concentrations of 24 elements in occipital scalp-hair samples from 134 adults living in Campania, southern Italy (67 women and 67 men; age range: 20–72 yr). Continuous models were restricted to elements detected in at least 70% of adults and were fitted using HC3 heteroskedasticity-consistent standard errors, with Benjamini–Hochberg correction for the false discovery rate (FDR). Ca, Zn, Mg, K and Cu were the most abundant elements in the hair profile. The most consistent adjusted association was lower concentrations of Ca, Mg, Cu, Cr and Zn in men. Pb showed a strongly right-skewed distribution, whereas Cd was detected in only 22.4% of adults; this low detection frequency did not support a population-level elevation claim. Spatial summaries and clustering were retained for exploratory purposes: Kruskal–Wallis tests indicated a zone-level difference only for Zn, whereas patterns in Pb, Cr, As, Cd, and V were interpreted as priorities for confirmatory sampling rather than as evidence of territorial risk. Sensitivity analyses based on the limit of detection (LOD) supported retaining As and Cd as descriptive outcomes; V associations were not promoted to primary findings because the V detection frequency was below the pre-specified threshold. These findings support the use of hair biomonitoring as a non-invasive screening approach in mixed geogenic–anthropogenic settings, provided that sex, sample mass, non-detects, outliers, and external contamination are considered explicitly and that confirmatory matrices are used where appropriate. Full article

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

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16 pages, 290 KB

Open AccessArticle

Consumer Risk Characterisation of Potentially Toxic Elements in European Seabass (Dicentrarchus labrax) Marketed in Hungary

by József Lehel, Keisuke Machida, András Bartha, Péter Palotás, Attila László Nagy, Orsolya Strang and Zsuzsa Farkas

Toxics 2026, 14(9), 767; https://doi.org/10.3390/toxics14090767 - 27 Aug 2026

Abstract

European seabass (Dicentrarchus labrax) is a widely consumed fish species and may contribute to dietary exposure to potentially toxic elements. This study analysed 40 seabass samples, originating from the Adriatic Sea (Croatia) and purchased at retail in Hungary, for total arsenic [...] Read more.

European seabass (Dicentrarchus labrax) is a widely consumed fish species and may contribute to dietary exposure to potentially toxic elements. This study analysed 40 seabass samples, originating from the Adriatic Sea (Croatia) and purchased at retail in Hungary, for total arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) concentrations using ICP-OES. Their concentrations in muscle tissue (mg/kg ww) were 1.44 ± 0.90 for total As (detected in 92.5% of samples), 0.06 ± 0.02 for Cd (detected in 35.0% of samples), and 0.25 ± 0.14 for Pb (detected in 27.5% of samples). Inorganic arsenic (iAs) was not measured directly but was conservatively estimated to be 5% of the total arsenic, resulting in an estimated concentration of 0.07 ± 0.05 mg/kg wet weight. All Hg results were below the analytical limit of detection (0.50 mg/kg). When compared with the EU maximum levels (ML), six samples (15%) exceeded the ML for Pb (0.30 mg/kg), thirteen samples (32.5%) exceeded the ML for Cd (0.05 mg/kg), and eight samples (20%) potentially exceeded the ML for iAs (0.1 mg/kg). Consumer risk was evaluated using a screening-level non-cancer risk characterisation framework based on the target hazard quotient (THQ) and hazard index (HI). Results below the LODs were handled using lower-, middle- and upper-bound substitution scenarios. Risk characterisation focused on EU-relevant consumption scenarios, including average adult consumptions, an adult high-consumer (P95) scenario, and child-specific scenarios using age-appropriate body weights. For average adult consumptions, the HI was below one under the lower-bound scenario but exceeded one under the middle- and upper-bound scenarios. However, under high-consumption conditions, lead was identified as the dominant contributor to elevated THQ and HI values, particularly in upper-bound scenarios and for sensitive population groups. These findings indicate that European seabass does not provide definitive evidence of a general population-level health risk; however, screening-level non-cancer concerns were identified under the mean adult middle- and upper-bound scenarios, as well as under high-consumption scenarios, underscoring the importance of continued monitoring and risk-based communication. Full article

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24 pages, 1816 KB

Open AccessArticle

Analysis of Ni, Cu, and Fe in Loose Cosmetic Products: A Preliminary Dermal Exposure and Health Risk Assessment

by Agnieszka Berdowska, Katarzyna Bandurska, Joanna Kończyk and Iwona Zawierucha

Toxics 2026, 14(9), 766; https://doi.org/10.3390/toxics14090766 - 27 Aug 2026

Abstract

Loose cosmetic products are widely used in everyday makeup application; however, they may constitute a source of consumer exposure to metals present either intentionally as structural mineral pigments or unintentionally as contaminants derived from raw materials. The aim of this study was to [...] Read more.

Loose cosmetic products are widely used in everyday makeup application; however, they may constitute a source of consumer exposure to metals present either intentionally as structural mineral pigments or unintentionally as contaminants derived from raw materials. The aim of this study was to quantitatively determine the concentrations of nickel, copper, and iron in loose facial cosmetics (including face powders, contouring products, and eyeshadows) available on the Polish market and to evaluate the potential human health risks. Following validated microwave digestion, the samples were analyzed using microwave plasma–atomic emission spectrometry (MP-AES). Non-carcinogenic and carcinogenic health risks were assessed for dermal exposure by calculating the Hazard Quotient (HQ), Hazard Index (HI), and lifetime cancer risk (LCR). The analyzed metals were detected in the majority of the tested products. Nickel was not detected in four cosmetic samples, whereas its concentration in the remaining products ranged from 0.45 to 37.57 mg/kg. Copper concentrations were between 0.83 and 35.39 mg/kg, while iron concentrations varied from 0.03 × 10³ to 109.56 × 10³ mg/kg. The calculated HQ and HI values (maximum HI = 8.91 × 10⁻⁵) were well below 1, indicating no significant non-carcinogenic health risk. The estimated lifetime cancer risk for nickel was within the safe range (5.63 × 10⁻¹² to 8.28 × 10⁻⁹). Chronic dermal exposure to the analyzed metals is therefore unlikely to pose either systemic toxic or carcinogenic risks to consumers. However, the detected levels of nickel and copper in the samples with the highest concentrations may trigger local allergic reactions in sensitized individuals. These findings highlight the importance of monitoring the purity of mineral raw materials used in cosmetic production. Full article

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24 pages, 2778 KB

Open AccessReview

Heavy Metal Pollution in River Sediments: Risk Assessment, Source Apportionment, and Remediation—A Review Focusing on Chinese River Basins

by Yuheng Tan, Jianqiao Qin, Binyi Tao, Huarong Zhao, Jinhuan Deng, Jiayin Ling, Min Dai and Xi Chen

Toxics 2026, 14(9), 765; https://doi.org/10.3390/toxics14090765 - 27 Aug 2026

Abstract

River sediments act not only as important sinks for heavy metal pollution in watersheds, but also as potential secondary sources under changing environmental conditions. Heavy metals can enter river systems through industrial wastewater discharge, agricultural non-point runoff, urban stormwater and sewage inputs, mining [...] Read more.

River sediments act not only as important sinks for heavy metal pollution in watersheds, but also as potential secondary sources under changing environmental conditions. Heavy metals can enter river systems through industrial wastewater discharge, agricultural non-point runoff, urban stormwater and sewage inputs, mining and smelting activities, and atmospheric deposition. During adsorption onto suspended particles, sedimentation, and resuspension, metals such as Cd, Pb, Cr, Cu, Zn, Ni, As, and Hg progressively accumulate in sediments. Because heavy metals are persistent, non-degradable, and bioaccumulative, contaminated sediments can record historical watershed pollution while also releasing metals back into overlying water under hydrodynamic disturbance, pH and redox fluctuations, organic matter mineralization, benthic bioturbation, and dredging activities, thereby threatening aquatic ecosystem stability and human health. Using a global methodological framework with particular emphasis on Chinese river basins, this review systematically summarizes key issues in the study of heavy metal pollution in river sediments, including spatial–temporal distribution and operationally defined fractionation, pollution levels and ecological risk assessment, source apportionment, and remediation and management technologies. Current evidence indicates that heavy metal contamination in river sediments exhibits pronounced spatial heterogeneity and watershed-specific characteristics. Its distribution is jointly controlled by geological background, land use patterns, source input intensity, hydrodynamic conditions, sediment particle size composition, and organic matter content. Methodologically, the field has evolved from single total concentration monitoring and exceedance-based evaluation toward integrated assessment systems that combine total concentrations, operationally defined fractionation, bioavailability, ecological risk, health risk, and source contribution. The joint use of BCR sequential extraction, the geoaccumulation index (Igeo), the pollution load index (PLI), the potential ecological risk index (RI), the risk assessment code (RAC), sediment quality guidelines (SQGs), receptor models, isotope tracing, and machine learning has substantially improved pollution identification, risk zoning, and source apportionment. Overall, research on heavy metal pollution in river sediments has shifted from descriptive judgments of whether contamination exists toward mechanistic and management-oriented questions concerning pollution sources, risk evolution, and remediation strategies. However, important gaps remain in compound pollution transformation mechanisms, regional background values and evaluation benchmarks, uncertainty in model parameters, long-term dynamic monitoring, and engineering-scale verification of remediation technologies. Future studies should strengthen multi-media, multi-scale, and long-term monitoring and further integrate fractionation analysis, toxicological effects, source apportionment models, and remediation technologies to provide a scientific basis for watershed ecological security and precision management of contaminated sediments. Full article

(This article belongs to the Special Issue Biomonitoring of Toxic Elements and Emerging Pollutants)

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26 pages, 13403 KB

Open AccessReview

Application and Mechanisms of Biochar in Anaerobic Digestion: Towards Process Resilience and Waste Valorization

by Yuan Shi, Yin Luo, Tingting Zhu and Kaijia Zang

Toxics 2026, 14(9), 764; https://doi.org/10.3390/toxics14090764 - 26 Aug 2026

Abstract

Anaerobic digestion (AD) is widely used for organic waste stabilization and bio-energy recovery, but its performance is often constrained by process instability, slow syntrophic metabolism, and sensitivity to acidification, ammonia, organic overloading, and inhibitory contaminants. Biochar has emerged as a promising strategy to [...] Read more.

Anaerobic digestion (AD) is widely used for organic waste stabilization and bio-energy recovery, but its performance is often constrained by process instability, slow syntrophic metabolism, and sensitivity to acidification, ammonia, organic overloading, and inhibitory contaminants. Biochar has emerged as a promising strategy to enhance AD, with benefits extending beyond increased methane yield. This review examines how biochar properties, including pore structure, surface functional groups, alkalinity, and electrical conductivity, regulate different AD stages and improve process stability. Biochar provides microbial habitats, buffers pH, adsorbs inhibitors, accelerates volatile fatty acid conversion, and facilitates interspecies electron transfer. The effects of biochar dosage, feedstock type, reactor configuration, and operational conditions on digestion performance and resource recovery are critically evaluated. Broader contributions to organic waste valorization are also discussed. Future research should prioritize tailored biochar design, standardized characterization, long-term validation in continuous reactors, techno-economic analysis, and life-cycle assessment. These efforts are essential for translating laboratory findings into reliable and sustainable applications for organic solid waste treatment and resource recovery. Full article

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19 pages, 4156 KB

Open AccessArticle

Determination of 25 Organophosphate Ester Flame Retardants in Soils by Accelerated Solvent Extraction–Ultra-High Performance Liquid Chromatography

by Ban Cao, Yinjun Shi, Zuguo Hu and Mingli Ye

Toxics 2026, 14(9), 763; https://doi.org/10.3390/toxics14090763 - 26 Aug 2026

Abstract

Organophosphate esters (OPEs) are commonly used flame retardants and plasticizers, which can easily be released into the soil environment and have potential hazards such as neurotoxicity and developmental toxicity. Establishing an efficient and sensitive detection method plays a crucial role in soil pollution [...] Read more.

Organophosphate esters (OPEs) are commonly used flame retardants and plasticizers, which can easily be released into the soil environment and have potential hazards such as neurotoxicity and developmental toxicity. Establishing an efficient and sensitive detection method plays a crucial role in soil pollution assessment. Currently, there have been numerous studies on the detection of OPEs in soil using ultrasonic extraction and solid-phase extraction, while relatively few studies have focused on the analysis of multiple OPEs in soil by accelerated solvent extraction combined with d-SPE clean-up and ultra-high performance liquid chromatography–tandem mass spectrometry. The d-SPE purification method eliminates the need for column passage, shortens sample preparation time, and avoids the risk of background contamination from OPEs that may be introduced by SPE. This study developed a liquid chromatography–tandem quadrupole mass spectrometry (LC-MS/MS) method for the determination of 25 OPEs in soil, and systematically optimized the pretreatment and instrumental analysis conditions. Accelerated solvent extraction was used for pretreatment, and dichloromethane–methanol (1:1, V/V) was determined as the optimal extraction solvent. A mixed adsorbent of N-propyl ethylenediamine (PSA) and C18 was selected for dispersive purification, effectively removing matrix interference and improving recovery rates. The mass spectrometry parameters such as collision energy and declustering voltage were optimized, significantly enhancing ion response intensity and detection sensitivity. The method showed good linearity within the concentration range of 1–100 ng/mL, with correlation coefficients all greater than 0.994. The spiked recovery rates ranged from 70.6% to 111% with a relative standard deviation (RSD) of 1.2–11.8%. The precision and accuracy met the requirements for environmental sample analysis. The method was applied to the detection of actual soil samples, and the results were stable and reliable. This method is simple to operate, highly sensitive, and widely applicable, providing reliable technical support for the pollution monitoring, source tracing, and ecological risk assessment of OPEs in soil. Full article

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

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12 pages, 506 KB

Open AccessArticle

Association Between Lifetime Cadmium Intake and Urinary Cadmium Concentration Among Residents of the Jinzu River Basin Following Soil Remediation

by Yu Fujiwara, Kazuhiro Nogawa, Masaru Sakurai, Yuuka Watanabe, Masao Ishizaki, Yasumitsu Ogra, Yu-ki Tanaka, Hirotaro Iwase, Kayo Tanaka, Teruhiko Kido, Hideaki Nakagawa and Yasushi Suwazono

Toxics 2026, 14(9), 762; https://doi.org/10.3390/toxics14090762 - 26 Aug 2026

Abstract

Cadmium (Cd), a widespread pollutant, is primarily absorbed via diet and smoking. Chronic Cd exposure has been associated with various adverse health effects, including renal tubular and skeletal damage. Urinary Cd concentration accurately reflects cumulative Cd exposure owing to its strong correlation with [...] Read more.

Cadmium (Cd), a widespread pollutant, is primarily absorbed via diet and smoking. Chronic Cd exposure has been associated with various adverse health effects, including renal tubular and skeletal damage. Urinary Cd concentration accurately reflects cumulative Cd exposure owing to its strong correlation with renal cortical Cd levels. This study evaluated the accuracy of estimated lifetime Cd intake by examining its correlation with urinary Cd levels after soil remediation, an aspect unreported even in the Kakehashi River Basin. A total of 565 men and 450 women were included. Lifetime Cd intake (g) was estimated using an established exposure assessment model that incorporated individual residential history, rice Cd concentrations, and dietary assumptions. Urinary Cd concentrations were determined using inductively coupled plasma mass spectrometry. Linear regression analyses were conducted between lifetime cadmium intake and urinary cadmium concentration. The obtained standardized regression coefficients were 0.49 for men and 0.54 for women (both p < 0.001), indicating strong associations. Despite possible exposure misclassification, these findings support the utility of lifetime cadmium intake as a useful surrogate indicator of cumulative cadmium exposure and provide further evidence for its application in risk assessment and the derivation of tolerable cadmium intake values. Full article

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

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24 pages, 341 KB

Open AccessArticle

Heavy Metal Contamination in Commercial Coffee Products in Saudi Arabia: Prevalence, Carcinogenic and Non-Carcinogenic Risk Assessment, and Implications for Diabetes and Cardiovascular Disease

by Azizah A. Algreiby, Suzan Makawi, Ahmed H. Bakheit and Abdullah H. Alluhayb

Toxics 2026, 14(9), 761; https://doi.org/10.3390/toxics14090761 - 26 Aug 2026

Abstract

Coffee is deeply embedded in Saudi culture and is among the most consumed beverages worldwide. However, contamination by toxic heavy metals may represent an underrecognized public health concern, particularly in regions already burdened by diabetes mellitus and cardiovascular disease. This study evaluated concentrations [...] Read more.

Coffee is deeply embedded in Saudi culture and is among the most consumed beverages worldwide. However, contamination by toxic heavy metals may represent an underrecognized public health concern, particularly in regions already burdened by diabetes mellitus and cardiovascular disease. This study evaluated concentrations of lead (Pb), cadmium (Cd), arsenic (As), chromium (Cr), and nickel (Ni) in 21 commercial coffee samples representing seven product categories marketed in Saudi Arabia. Samples were prepared using EPA Method 3050B acid digestion and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Health risks were assessed through estimated daily intake (EDI), hazard quotient (HQ), hazard index (HI), and incremental lifetime cancer risk (ILCR) using USEPA exposure parameters and Saudi-specific coffee consumption data. All metals were detected in every sample. Mean concentrations (mg/kg dry weight) were 1.638 for Pb, 0.560 for Cd, 0.622 for Cr, 0.536 for Ni, and 0.034 for As. Cadmium exceeded the European Union maximum limit for roasted coffee in all samples, while elevated Pb levels were observed in dark roast and Yemeni coffees. Although the overall non-carcinogenic risk remained below the accepted threshold (HI = 0.438), the combined ILCR for As, Cd, and Pb was 5.84 × 10⁻⁵. Inclusion of a conservative screening-level chromium contribution, calculated by assuming that all measured total Cr was present as Cr(VI), increased the upper-bound total ILCR to 9.38 × 10⁻⁵. This value remained within, but approached the upper boundary of, the risk-management range applied in this study. These findings highlight the need for strengthened monitoring and regulatory control of coffee products in Saudi Arabia. Full article

(This article belongs to the Section Agrochemicals and Food Toxicology)

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8 pages, 207 KB

Open AccessCommunication

Hormonal Activity of 3D Bioprinting Materials Using the E-Screen and PALM Bioassays

by Alicia Olivas-Martinez, Elisa Nygren-Jiménez, Jose Manuel Molina-Molina, Gema Jiménez, Mariana F. Fernández and Juan Antonio Marchal

Toxics 2026, 14(9), 760; https://doi.org/10.3390/toxics14090760 - 26 Aug 2026

Abstract

Three-dimensional (3D) printing and bioprinting technologies are increasingly used in tissue engineering and in the development of personalized medical devices with tailored biological and mechanical properties. Despite their advantages, these technologies may involve exposure to chemical compounds with uncertain biological effects, including potential [...] Read more.

Three-dimensional (3D) printing and bioprinting technologies are increasingly used in tissue engineering and in the development of personalized medical devices with tailored biological and mechanical properties. Despite their advantages, these technologies may involve exposure to chemical compounds with uncertain biological effects, including potential endocrine-disrupting activity. This study aims to evaluate the hormonal activity and cytotoxicity of various materials commonly used for 3D printing technologies, including thermoplastics and synthetic materials (PLA, ABS, PCL, b-TPUe, PVA, PEGDA), and biomaterials (collagen, alginate, hyaluronic acid, agarose, silk fibroin, GelMA, HAMA). Hormonal activity was evaluated using the E-screen assay for estrogenic and anti-estrogenic activity, and the PALM assay for androgenic and anti-androgenic activity. Cytotoxic effects are evaluated by assessing cellular metabolic viability using the MTT assay. No detectable estrogenic, anti-estrogenic, androgenic, or anti-androgenic activity, nor any signs of cytotoxicity, were observed within the experimental conditions analysed. This study represents the first analysis of some specific endocrine-related endpoints of a wide range of 3D printing and bioprinting materials, and should not be interpreted as definitive proof of the complete absence of endocrine activity. Further studies addressing additional toxicological parameters and long-term assessments are required to comprehensively characterize their safety and suitability. Full article

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