Assessing the external atmospheric input of microplastics: Two strategies based on polymer composition and aging characteristics.

Microplastics (MPs) can be transported over long distances in the environment, hence, distinguishing between MPs generated locally and those introduced from external sources is necessary for regional MP pollution management. In this study, MPs pollution in the dust of Siziwang banner (Sizi), a sparsely populated area on the Mongolian Plateau, and Hohhot, a city with large populations, was observed. The high proportion of small MPs in Sizi (<25 µm), combined with the fact that most air masses reaching the area have undergone long-distance transport, supports the presence of external input through atmosphere. Based on the significantly different composition distributions and surface characteristics of the small sized MPs in Sizi and Hohhot, a composition-based Bray-Curtis similarity index (Comp-BCs) and a carbonyl index-based BCs index (CI-BCs) were established. Contributions of the external MPs input to small MPs in Sizi were estimated as 23-36 %, indicating that the role of atmospheric input on MPs pollution in sparsely populated areas should not be overlooked.

Machine Learning Models for Predicting Bioavailability of Traditional and Emerging Aromatic Contaminants in Plant Roots.

To predict the behavior of aromatic contaminants (ACs) in complex soil-plant systems, this study developed machine learning (ML) models to estimate the root concentration factor (RCF) of both traditional (e.g., polycyclic aromatic hydrocarbons, polychlorinated biphenyls) and emerging ACs (e.g., phthalate acid esters, aryl organophosphate esters). Four ML algorithms were employed, trained on a unified RCF dataset comprising 878 data points, covering 6 features of soil-plant cultivation systems and 98 molecular descriptors of 55 chemicals, including 29 emerging ACs. The gradient-boosted regression tree (GBRT) model demonstrated strong predictive performance, with a coefficient of determination (R2) of 0.75, a mean absolute error (MAE) of 0.11, and a root mean square error (RMSE) of 0.22, as validated by five-fold cross-validation. Multiple explanatory analyses highlighted the significance of soil organic matter (SOM), plant protein and lipid content, exposure time, and molecular descriptors related to electronegativity distribution pattern (GATS8e) and double-ring structure (fr_bicyclic). An increase in SOM was found to decrease the overall RCF, while other variables showed strong correlations within specific ranges. This GBRT model provides an important tool for assessing the environmental behaviors of ACs in soil-plant systems, thereby supporting further investigations into their ecological and human exposure risks.

Structure-Dependent Distribution, Metabolism, and Toxicity Effects of Alkyl Organophosphate Esters in Lettuce (Lactuca sativa L.).

This study provides a comprehensive investigation into the structure-dependent uptake, distribution, biotransformation, and potential toxicity effects of alkyl organophosphate esters (OPEs) in hydroponic lettuce (Lactuca sativa L.). Trimethyl, triethyl, and tripropyl phosphates were readily absorbed and acropetally translocated, while tributyl, tripentyl, and trihexyl phosphates accumulated mainly in lateral roots. The acropetal translocation potential was negatively associated with log Kow values. Trimethyl and triethyl phosphates are less prone to biotransformation, while a total of 14 novel hydrolysis, hydroxylated, and conjugated metabolites were identified for other OPEs using nontarget analysis. The extent of hydroxylation decreases from tripropyl phosphate to trihexyl phosphate, but multiple hydroxylations occurred more frequently on longer chain OPEs. Further comparative toxicity test revealed that hydrolyzed and hydroxylated metabolites have stronger toxic effects on Ca2+-dependent protein kinases (CDPK) than their parent OPEs. Dibutyl 3-hydroxybutyl phosphate particularly induces upregulation of CDPK in lateral roots of lettuce, probably associated with adenine reduction that may play an important role in the self-defense and detoxification processes. This study contributes to understanding the uptake and transformation behaviors of alkyl OPEs as well as their associations with a toxic effect on lettuce. This emphasizes the necessary evaluation of the environmental risk of the use of OPEs, particularly focusing on their hydroxylated metabolites.

Foliar Uptake and Distribution of Metallic Oxide Nanoparticles in Maize (Zea mays L.) Leaf.

The foliar uptake of Fe3O4, Cr2O3, CuO, and ZnO nanoparticles (NPs) by maize (Zea mays L.) was studied in a lab-scale experiment. The significant increase of Fe concentrations in leaves exposed to Fe3O4 was observed in both stomatal closing and stomatal opening treatments, suggesting the presence of a nonstomatal uptake. In parallel treatments with equal doses of Fe3O4 (∼200 nm), Cr2O3 (∼300 nm), CuO (∼30 nm), and ZnO (∼40 nm) (20-200 µg), the retention percentage of Fe in the leaves (21.0-69.0%) was higher than that of Cr, Cu, and Zn (0.5-14.0%). The steric hindrance effect seems more important for NPs of >200 nm, while hydrophobic surface and negative charge promote the foliar uptake of NPs smaller than 200 nm. The accumulation of NPs in the cuticle was observed through dark-field hyperspectral microscopy. Cr2O3, Fe3O4, and CuO NPs were difficult to penetrate the cuticle. In comparison, ZnO further migrated and distributed within the extracellular space of epidermal and mesophyll cells of the exposed leaf, possibly due to its comparatively higher solubility and hydrophilicity. The findings highlight the potential of the nonstomatal uptake, which might be a critical route for metallic oxide NPs to enter the food chain.

Volatile organic compound exposure in relation to lung cancer: Insights into mechanisms of action through metabolomics.

Volatile organic compounds (VOCs) have proven to be hazardous to the human respiratory system. However, the underlying biological mechanisms remain poorly understood. Therefore, targeted determination of eleven VOC metabolites (mVOCs) along with the nontargeted metabolomic analysis was performed on urine samples collected from lung cancer patients and healthy individuals. Nine mVOCs mainly derived from aldehydes, alkenes, amides, and aromatics were detected in > 90 % of the urine samples, suggesting that the participants were ubiquitously exposed to these typical VOCs. A molecular gatekeeper discovery workflow was employed to link the exposure biomarkers with correlated clusters of endogenous metabolites. As a result, multiple metabolic pathways, including amino acid metabolism, steroid hormone biosynthesis and metabolism, and fatty acid ß-oxidation were connected with VOC exposure. Furthermore, 16 of 73 molecular gatekeepers were associated with lung cancer and pointed to a few disrupted metabolic pathways related to hydroxysteroids and acylcarnitine. The shift in molecular profiles was validated in rat model post VOC administration. Thereinto, the up-regulation of enzymes involved in acylcarnitine synthesis and transport in rat lung tissues highlighted that the mitochondrial dysfunction may be a potential carcinogenic mechanism. Our findings provide new insights into the mechanisms underlying lung cancer induced by VOC exposure.

Identification of Emerging Per- and Polyfluoroalkyl Substances (PFAS) in E-waste Recycling Practices and New Precursors for Trifluoroacetic Acid.

Electronic waste is an emerging source of per- and polyfluoroalkyl substance (PFAS) emissions to the environment, yet the contribution from hazardous recycling practices in the South Asian region remains unclear. This study detected 41 PFAS in soil samples from e-waste recycling sites in Pakistan and the total concentrations were 7.43-367 ng/g dry weight (dw) (median: 37.7 ng/g dw). Trifluoroacetic acid (TFA) and 6:2 fluorotelomer sulfonic acid emerged as the dominant PFAS, constituting 49% and 13% of the total PFAS concentrations, respectively. Notably, nine CF3-containing emerging PFAS were identified by the high-resolution mass spectrometry (HRMS)-based screening. Specifically, hexafluoroisopropanol and bistriflimide (NTf2) were consistently identified across all the samples, with quantified concentrations reaching up to 854 and 90 ng/g dw, respectively. This suggests their potential association with electronic manufacturing and recycling processes. Furthermore, except for NTf2, all the identified emerging PFAS were confirmed as precursors of TFA with molar yields of 8.87-40.0% by the TOP assay validation in Milli-Q water. Overall, this study reveals significant emission of PFAS from hazardous e-waste recycling practices and emphasizes the identification of emerging sources of TFA from precursor transformation, which are essential for PFAS risk assessment.

End-of-life vehicle dismantling activity emits large quantities of phthalates and their alternatives: New insights on environmental sources and co-exposure risks.

Automotive interiors have been identified as significant sources of various chemicals, yet their occupational hazards for end-of-life vehicle (ELV) dismantlers remain poorly characterized. Herein, eight classes of plasticizers, including 11 phthalates esters (PAEs) and 16 non-phthalates esters (NPAEs), were detected in dust samples from inside and outside ELV dismantling workshops. Moreover, indoor dust from ordinary households and university dormitories was compared. The indoor dust from the ELV dismantling workshops contained the highest concentrations of plasticizers (median: 594 µg/g), followed by ordinary households (296 µg/g), university dormitories (186 µg/g), and outdoor dust (157 µg/g). PAEs remained the dominant plasticizers, averaging 11.7-fold higher than their NPAE alternatives. Specifically, diisononyl phthalate and trioctyl trimellitate were notably elevated in workshop dust, being 15.5 and 4.78 times higher, respectively, than in ordinary household dust, potentially indicating their association with ELV dismantling activities. The estimated daily intake of occupational ELV dismantling workers was up to five times higher than that of the general population. Moreover, certain dominant NPAEs demonstrated nuclear receptor interference abilities comparable to typical PAEs, suggesting potential toxic effects. This study is the first to demonstrate that ELV dismantling activities contribute to the co-emission of PAEs and NPAEs, posing a substantial risk of exposure to workers, which warrants further investigation.

The regulating mechanisms of Triton X-100 affected oxidation of PAHs in site soil aggregates using sodium citrate assisted Fe2+-persulfate.

Here, we present a first investigation of the inhibition mechanism of surfactant Triton X-100 (TX-100) on the oxidation degradation of polycyclic aromatic hydrocarbons (PAHs) in site soil aggregates using sodium citrate assisted Fe2+-activated persulfate (SC/Fe2+/PS). First, TX-100 was not only competed the adsorption sites of soil aggregates with PS, but also consumed PS, which inhibit the PAHs remediation rate in the TX-100 elution followed by the SC/Fe2+/PS oxidation system from 55.6 % in the oxidation system to 50.3 %. Furthermore, in the oxidation followed by elution system, PAHs was adsorbed on the iron minerals produced during the oxidation, which would be form a bound PAHs that was difficult to react with PS, and then re-eluted to the soil by the TX-100. Additionally, it was found that the oxidative and the elution efficiency of PAHs exhibited negative correlations with aggregate particle sizes. Finally, soil microorganism communities were more strongly changed by SC/Fe2+/PS oxidation and PAHs concentration than that of TX-100 elution, with obvious alterations bacteria than fungi, the effects of SC/Fe2+/PS and PAHs concentration on microorganism communities were opposite. This study provided a proof of regulating mechanisms for the site soil remediation using surfactants combined with the iron-PS system.

Insights into the Enantiomeric Uptake, Translocation, and Distribution of Triazole Chiral Pesticide Mefentrifluconazole in Wheat (Triticum aestivum L.).

The uptake, translocation, and accumulation of mefentrifluconazole (MFZ), an innovative chiral triazole fungicide, in plants at the enantiomeric level are still unclear. Herein, we investigated the patterns and mechanisms of enantiomeric uptake, bioaccumulation, and translocation through several experiments. Rac-MFZ shows the strongest uptake and bioaccumulation capacity in wheat compared with its enantiomers, while S-(+)-MFZ has the highest translocation potential. Molecular docking provided evidence of the stronger translocation ability of S-(+)-MFZ than R-(-)-MFZ. Split-root experiments showed that MFZ and its enantiomers could undergo long-distance transport within the wheat. Active transport or facilitated and simple diffusion may be involved in the wheat uptake of MFZ. The limited acropetal translocation capability of MFZ may be attributed to the dominant uptake pathway of apoplastic. The concentrations of Rac-MFZ in different subcellular fractions varied greatly. In summary, this study provides novel insights for further understanding the behaviors of MFZ and its enantiomers in plants.

A novel cobalt-iron bimetallic hydrochar for the degradation of triclosan in the aqueous solution: performance, reusability, and synergistic degradation mechanism.

Low activation performance is a critical issue limiting the practical application of low-cost biochar in the advanced oxidation. Given the high potential of transition metals in the persulfate activation process and abundant oxygen-containing groups of hydrochar, hydrochar derived from cobalt (Co)-modified iron (Fe)-enriched sludge was synthesized and its performance and activation mechanism for the degradation of triclosan were investigated. Co modification significantly altered the morphology of hydrochar, and the increased Co-Fe mass ratios transformed hydrochar from granular to rose-shaped lamellar and then to helical sheet structures. Specific surface area, defect degree, and oxygen-containing groups of hydrochar increased with increasing cobalt-iron mass ratios. The highest removal of triclosan was up to 98% in the hydrochar/peroxymonosulfate (PMS) system under a wide range of pHs (3-10) and still remained higher than 90% after four cycles. Both Radical (mainly hydroxyl radical) and nonradical pathways (singlet oxygen and electron transfer) were evidenced to play roles in the triclosan removal. Fe3+ promoted the regeneration of Co2+ and realized the efficient circulation of Co3+/Co2+. A ternary system consisting of electron donor (triclosan)-electron mediator (hydrochar)-electron acceptor (PMS) provided channels for electron transfer. No measurable Co and Fe were released during the reaction, and the toxicity of degradation intermediates was lower than that of triclosan. Beside triclosan, rhodamine B, bisphenol A, sulfamethoxazole, and phenol were also almost degraded completely in this oxidation system. This study provides a promising way for the enhancement of catalytic activity of carbonaceous material.

Fluorotelomer betaines and sulfonic acid in aerobic wetland soil: Stability, biotransformation, and bacterial community response.

The microbial degradation of 6:2 fluorotelomer sulfonic acid (6:2 FTSA), fluorotelomer sulfonamide alkylbetaine (6:2 FTAB), and fluorotelomer betaines (5:3 and 5:1:2 FTB) in aerobic wetland soil was investigated during a 100-day incubation. The half-lives of 6:2 FTSA in the treatments with diethylene glycol butyl ether as the sole carbon source (NA treatment) and with additional supplementation of sodium acetate (ED treatment) were determined to be 26.2 and 16.7 days, respectively. By day 100, ∼20 mol% of 6:2 FTAB was degraded in the NA and ED treatments. The potential transformation products of 6:2 FTSA and 6:2 FTAB were identified using liquid/gas chromatography-high resolution mass spectrometry, and their biotransformation pathways were proposed. In contrast, 5:3 and 5:1:2 FTB exhibited high persistence under two carbon source conditions. There was no intense alteration in the diversity of soil bacterial communities under the stress of fluorotelomer compounds at the level of ∼150 µg/L. The supplementation of sodium acetate led to an enrichment of bacterial species within the genera Hydrogenophaga (phylum Proteobacteria) and Rhodococcus (phylum Actinobacteria), promoting the biodegradation of 6:2 FTSA and 6:2 FTAB and the formation of transformation products. Species from the genus Rhodococcus were potentially crucial functional microorganisms involved in the degradation of 6:2 FTSA.

Plastic takeaway food containers may cause human intestinal damage in routine life usage: Microplastics formation and cytotoxic effect.

The microplastics and organic additives formed in routine use of plastic takeaway food containers may pose significant health risks. Thus, we collected plastic containers made of polystyrene, polypropylene, polyethylene terephthalate, polylactic acid and simulated two thermal usages, including hot water (I) and microwave treatments (M). Nile Red fluorescence staining was developed to improve accurate counting of microplastics with the aid of TEM and DLS analysis. The quantity of MPs released from thermal treatments was determined ranging from 285.7 thousand items/cm2 to 681.5 thousand items/cm2 in containers loaded with hot water with the following order: IPS>IPP>IPET>IPLA, while microwave treatment showed lower values ranging from 171.9 thousand items/cm2 to 301.6 thousand items/cm2. In vitro toxicity test using human intestinal epithelial Caco-2 cells indicated decrease of cell viability in raw leachate, resuspended MPs and supernatants, which might further lead to cell membrane rupture, ROS production, and decreased mitochondrial membrane potential. Moreover, the leachate inhibited the expression of key genes in the electron transport chain (ETC) process, disrupted energy metabolism. For the first time, we isolate the actually released microplastics and organic substances for in vitro toxicity testing, and demonstrate their potential impacts to human intestine. SYNOPSIS: Plastic take-out containers may release microplastics and organic substances during daily usage, both of which can cause individual and combined cytotoxic effects on human colon adenocarcinoma cells Caco-2.

Multimedia distribution and release characteristics of emerging PFAS in wastewater treatment plants in Tianjin, China.

Legacy and emerging PFAS in the air, wastewater, and sludge from two wastewater treatment plants (WWTPs) in Tianjin were investigated in this study. The semi-quantified nontarget PFAS accounted for up to 99 % of Æ©PFAS in the gas phase, and aqueous film-forming foam (AFFF)-related PFAS were predominant in wastewater (up to 2250 ng/L, 79 % of Æ©PFAS) and sludge (up to 4690 ng/g, 95 % of Æ©PFAS). Furthermore, field-derived air particle-gas, air-wastewater, and wastewater particle-wastewater distribution coefficients of emerging PFAS are characterized, which have rarely been reported. The emerging substitute p-perfluorous nonenoxybenzenesulfonate (OBS) and AFFF-related cationic and zwitterionic PFAS show a stronger tendency to partition into particle phase in air and wastewater than perfluorooctane sulfonic acid (PFOS). The estimated total PFAS emissions from the effluent and sludge of WWTP A were 202 kg/y and 351 kg/y, respectively. While the target PFAS only accounted for 20-33 % of the total emissions, suggesting a significant underestimation of environmental releases of the nontarget PFAS and unknown perfluoroalkyl acid precursors through the wastewater and sludge disposal. Overall, this study highlights the importance of comprehensive monitoring and understanding the behavior of legacy and emerging PFAS in wastewater systems, and fills a critical gap in our understanding of PFAS exposure.

Emerging contaminants: A One Health perspective.

Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy pollutants, the continuous introduction of new substances remains a major threat to both people and the planet. In response, global initiatives are focusing on risk assessment and regulation of emerging contaminants, as demonstrated by the ongoing efforts to establish the UN's Intergovernmental Science-Policy Panel on Chemicals, Waste, and Pollution Prevention. This review identifies the sources and impacts of emerging contaminants on planetary health, emphasizing the importance of adopting a One Health approach. Strategies for monitoring and addressing these pollutants are discussed, underscoring the need for robust and socially equitable environmental policies at both regional and international levels. Urgent actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.

Contamination Status of Novel Organophosphate Esters Derived from Organophosphite Antioxidants in Soil and the Effects on Soil Bacterial Communities.

The contamination status of novel organophosphate esters (NOPEs) and their precursors organophosphite antioxidants (OPAs) and hydroxylated/diester transformation products (OH-OPEs/di-OPEs) in soils across a large-scale area in China were investigated. The total concentrations of the three test NOPEs in soil were 82.4-716 ng g-1, which were considerably higher than those of traditional OPEs (4.50-430 ng g-1), OPAs (n.d.-30.8 ng g-1), OH-OPEs (n.d.-0.49 ng g-1), and di-OPEs (0.57-21.1 ng g-1). One NOPE compound, i.e., tris(2,4-di-tert-butylphenyl) phosphate (AO168 = O) contributed over 65% of the concentrations of the studied OPE-associated contaminants. A 30-day soil incubation experiment was performed to confirm the influence of AO168 = O on soil bacterial communities. Specific genera belonging to Proteobacteria, such as Lysobacter and Ensifer, were enriched in AO168 = O-contaminated soils. Moreover, the ecological function of methylotrophy was observed to be significantly enhanced (t-test, p < 0.01) in soil treated with AO168 = O, while nitrogen fixation was significantly inhibited (t-test, p < 0.01). These findings comprehensively revealed the contamination status of OPE-associated contaminants in the soil environment and provided the first evidence of the effects of NOPEs on soil microbial communities.

Human exposure characteristics of pharmaceutical and personal care product chemicals and associations with dietary habits.

Considering the widespread presence of pharmaceutical and personal care products (PPCPs) in the environment and their adverse health effects, human exposure to PPCPs has caused worldwide concern. However, there remains insufficient information on the exposure assessment of the Chinese population. Based on this, the exposure levels of 13 PPCPs in the urine samples of 986 Chinese adults were measured, aiming to provide information on the prevalence of PPCP occurrence and investigate potential correlations between PPCP exposure and obesity. Results showed that the detection rates of these compounds in urine ranged from 28.12 % to 98.58 %, with median concentrations ranging below the limit of detection to 10.58 ng mL-1. Methyl-paraben (MeP) was the most dominant paraben and had the highest urinary concentration (median = 10.12 ng mL-1), while 4-hydroxy-benzophenone (4-OH-BP) was the dominant benzophenone derivative (median = 0.22 ng mL-1). In antibacterials, the urinary concentration of triclosan (mean = 42.00 ng mL-1) was much higher than that of triclocarban (mean = 0.63 ng mL-1). PPCP concentrations were significantly associated with sex, age, body mass index, education level, and annual household income (p < 0.050). Regression analysis of dietary habits showed that seafood and tea consumption may be significant exposure sources of PPCP exposure (p < 0.050). Furthermore, individual exposure to MeP (odds ratio (OR) < 1, p = 0.002) and 4-OH-BP (OR < 1, p = 0.009) exhibited a significantly negative association with obesity in females. Also, analysis results from quantile g-computation and Bayesian kernel machine regression models demonstrated that an inverse correlation between PPCP mixture exposure and obesity was significant in females. This study reports the extensive prevalence of PPCP exposure among adults from China, and may provide crucial insights into PPCP exposure dynamics. More epidemiological studies are need in the future, with a thorough knowledge of PPCP exposure.

The role of iron materials in the abiotic transformation and biotransformation of polybrominated diphenyl ethers (PBDEs): A review.

Polybrominated diphenyl ethers (PBDEs), widely used as flame retardants, easily enter the environment, thus posing environmental and health risks. Iron materials play a key role during the migration and transformation of PBDEs. This article reviews the processes and mechanisms of adsorption, degradation, and biological uptake and transformation of PBDEs affected by iron materials in the environment. Iron materials can effectively adsorb PBDEs through hydrophobic interactions, π-π interactions, hydrogen/halogen bonds, electrostatic interactions, coordination interactions, and pore filling interactions. In addition, they are beneficial for the photodegradation, reduction debromination, and advanced oxidation degradation and debromination of PBDEs. The iron material-microorganism coupling technology affects the uptake and transformation of PBDEs. In addition, iron materials can reduce the uptake of PBDEs in plants, affecting their bioavailability. The species, concentration, and size of iron materials affect plant physiology. Overall, iron materials play a bidirectional role in the biological uptake and transformation of PBDEs. It is necessary to strengthen the positive role of iron materials in reducing the environmental and health risks caused by PBDEs. This article provides innovative ideas for the rational use of iron materials in controlling the migration and transformation of PBDEs in the environment.

A ferroptosis-related signature predicts the clinical diagnosis and prognosis, and associates with the immune microenvironment of lung cancer.

Targeting ferroptosis-related pathway is a potential strategy for treatment of lung cancer (LC). Consequently, exploration of ferroptosis-related markers is important for treating LC. We collected LC clinical data and mRNA expression profiles from TCGA and GEO database. Ferroptosis-related genes (FRGs) were obtained through FerrDB database. Expression analysis was performed to obtain differentially expressed FRGs. Diagnostic and prognostic models were constructed based on FRGs by LASSO regression, univariate, and multivariate Cox regression analysis, respectively. External verification cohorts GSE72094 and GSE157011 were used for validation. The interrelationship between prognostic risk scores based on FRGs and the tumor immune microenvironment was analyzed. Immunocytochemistry, Western blotting, and RT-qPCR detected the FRGs level. Eighteen FRGs were used for diagnostic models, 8 FRGs were used for prognostic models. The diagnostic model distinguished well between LC and normal samples in training and validation cohorts of TCGA. The prognostic models for TCGA, GSE72094, and GSE157011 cohorts significantly confirmed lower overall survival (OS) in high-risk group, which demonstrated excellent predictive properties of the survival model. Multivariate Cox regression analysis further confirmed risk score was an independent risk factor related with OS. Immunoassays revealed that in high-risk group, a significantly higher proportion of Macrophages_M0, Neutrophils, resting Natural killer cells and activated Mast cells and the level of B7H3, CD112, CD155, B7H5, and ICOSL were increased. In conclusion, diagnostic and prognostic models provided superior diagnostic and predictive power for LC and revealed a potential link between ferroptosis and TIME.

Aromatic amine antioxidants (AAs) and p-phenylenediamines-quinones (PPD-Qs) in e-waste recycling industry park: Occupational exposure and liver X receptors (LXRs) disruption potential.

Recently, evidence of aromatic amine antioxidants (AAs) existence in the dust of the electronic waste (e-waste) dismantling area has been exposed. However, there are limited studies investigating occupational exposure and toxicity associated with AAs and their transformation products (p-phenylenediamines-quinones, i.e., PPD-Qs). In this study, 115 dust and 42 hand wipe samples collected from an e-waste recycling industrial park in central China were analyzed for 19 AAs and 6 PPD-Qs. Notably, the median concentration of ∑6PPD-Qs (1,110 ng/g and 1,970 ng/m2) was significantly higher (p < 0.05, Mann-Whitney U test) than that of ∑6PPDs (147 ng/g and 34.0 ng/m2) in dust and hand wipes. Among the detected analytes, 4-phenylaminodiphenylamine quinone (DPPD-Q) (median: 781 ng/g) and 1,4-Bis(2-naphthylamino) benzene quinone (DNPD-Q) (median: 156 ng/g), were particularly prominent, which were first detected in the e-waste dismantling area. Occupational exposure assessments and nuclear receptor interference ability, conducted through estimated daily intake (EDI) and molecular docking analysis, respectively, indicated significant occupational exposure to PPD-Qs and suggested prioritized Liver X receptors (LXRs) disruption potential of PPDs and PPD-Qs. The study provides the first evidence of considerable levels of AAs and PPD-Qs in the e-waste-related hand wipe samples and underscores the importance of assessing occupational exposure and associated toxicity effects.

Preparation of novel Fe-containing zeolite-A for KN-R decolorization by Fenton-like reaction.

Herein, novel catalysts of Fe-containing zeolite-A (Fe/zeolite-A) were synthesized by exchanging iron ions into zeolite-A framework, and short-chain organic acids (SCOAs) were employed as chelating agents. Reactive Brilliant Blue KN-R (KN-R) was used as a model pollutant to evaluate the performance of these catalysts based on the heterogeneous Fenton reaction. The results showed that Fe-OA/3A, which applied zeolite-3A as the supporter and oxalic as the chelating agent, presented the most prominent KN-R decolorization efficiency. Under the initial pH of 2.5, 0.4 mM KN-R could be totally decolorized within 20 min. However, the mineralization efficiency of KN-R was only 58.2%. Therefore, anthraquinone dyes were introduced to modify zeolite-3A. As a result, the mineralization efficiency of KN-R was elevated to 92.7% when using Alizarin Violet (AV) as the modifier. Moreover, the modified catalysts exhibited excellent stability, the KN-R decolorization efficiency could be maintained above 95.0% within 20 min after operating for nine cycles. The mechanism revealed that the Fe(II)/Fe(III) cycle was accelerated by AV-modified catalyst thus prompting the KN-R decolorization in Fenton-like system. These findings provide new insights for preparing catalysts with excellent activity and stability for dye wastewater treatment.