In this work, ZnO–CdWO₄ nanoparticles have been synthesized by the ecofriendly green method with lemon leaf extract to favorably anchor functional groups on their surface. The prepared ZnO–CdWO₄ nanoparticles are used as adsorbent to treat Congo red (CR) dye after characterization through FT-IR, UV–Vis, TEM, SEM-EDX, and HRTEM techniques. The equilibrium partition coefficient and adsorption capacity values for CR by ZnO–CdWO₄ are estimated as 21.4 mg g⁻¹ μM⁻¹ and 5 mg g⁻¹, respectively (at an initial dye concentration of 10 mg L⁻¹). The adsorption process is found as exothermic and spontaneous, as determined by the ΔG°, ΔS°, and ΔH° values. The Boyd plot has been used as a confirmatory tool to fit the adsorption kinetics data along with intraparticle diffusion and pseudo-second-order models. Based on this research, ZnO–CdWO₄ nanoparticles are validated as an effective adsorbent for CR dye in aqueous solutions.

The increasing salinization of groundwater renders it challenging to maintain the water quality. Moreover, knowledge regarding the characteristics and mechanism of groundwater salinization in mining areas remains limited. This study represents the first attempt of combining the hydrochemical, isotope (δD, δ¹⁸O, δ³⁷Cl, and ⁸⁷Sr/⁸⁶Sr) and multivariate statistical analysis methods to explore the origin, control, and influence of fluoride enrichment in mining cities. The TDS content of groundwater ranged from 275.9 mg/L to 2452.0 mg/L, and 54% of the groundwater samples were classified as class IV water according to China's groundwater quality standards (GB/T 14848–2017), indicating a decline in the water quality of the study area. The results of the groundwater ion ratio and isotope discrimination analysis showed that dissolution and evaporation involving water-rock interactions and halite were the main driving processes for groundwater salinization in the study area. In addition to the hydrogeological and climatic conditions, mine drainage inputs exacerbated the increasing salinity of the groundwater in local areas. The mineral dissolution, cation exchange, and evaporation promoted the F⁻ enrichment, while excessive evaporation and salinity inhibited the F⁻ enrichment. Gangue accumulation and infiltration likely led to considerable F⁻ enrichment in individual groundwater regions. Extensive changes in the groundwater salinity indicated differences in the geochemical processes that controlled the groundwater salinization. Given the particularity of the study area, the enrichment of salinization and fluoride triggered by mining activities cannot be ignored.

PM₂.₅ and PM₁₀ fugitive dust samples from multiple sources (construction, demolition, industrial, agricultural fields, and bare ground) were collected in triplicate for each size bin, from 18 distinct locations in and around Bhopal, central India. The dust samples were dried, sieved, and re-suspended in a chamber fitted with a suitable sampling system, to collect PM₂.₅ and PM₁₀ samples onto Teflon and Quartz filters. The filters were subjected to gravimetric and chemical analyses. Trace elements, water-soluble ions, and thermal-optical carbon fractions were quantified using a variety of analyses. These species were then used to develop PM₁₀ and PM₂.₅ chemical source profiles of the fugitive dust sources. As expected, crustal species were abundant in all source categories. For industrial dust, Fe contribution to mass in both size fractions was about 11.4% and above the upper continental crustal abundance. Further, the source profiles generated for each source were different from their counterparts in the US EPA SPECIATE database and profiles reported in literature. Thus, it will be useful to utilize profiles generated in this study to enhance receptor model performance for the study region. However, collinearity analysis of the profiles revealed that PM₁₀ agricultural and bare ground dust; and PM₂.₅ construction and demolition dust profile pairs may not be separated by receptor models. Finally, a human health risk assessment revealed that construction and industrial dust may pose significant risk to the population. The Incremental Lifetime Cancer Risk (ILCR) metric revealed that adults (2 × 10⁻⁵) and children (1 × 10⁻⁵) were susceptible to cancer risk from exposure to metals in PM₂.₅ fugitive dust. Further, children were more vulnerable than adults. This finding merits further investigation of oxidation state and solubility/bioavailability of Cr and Ni in fugitive dusts.

Mercury (Hg) pollution in the ocean is an issue of global concern, however bioaccumulation regimes of this ubiquitous pollutant in marine apex predators have important knowledge gaps. Our fish length and stable isotope (δ¹⁵N and δ¹³C) normalized data of Greenland halibut (GH) (Reinhardtius hippoglossoides) showed that Hg bioaccumulation in fillet tissue decreased by ~35–50 %, over a ten-year period from 2006 to 2015 (n = 7 individual sampling years). Hg was predominantly in the methylmercury form (>77 %). Results from a Bayesian information theoretic model showed that GH Hg concentrations decreased with time and its associated declines in Hg air emissions, estimated trophic position, and a potentially lower degree of demersal prey use as indicated by temporal trend shifts in nitrogen (δ¹⁵N) and carbon (δ¹³C) stable isotope values. GH trophic shifts accounted for about one third of the observed temporal reduction in Hg. Our study demonstrates the importance of simultaneously considering Hg emissions, food web dynamics and trophic shifts as important drivers of Hg bioaccumulation in a marine, deep water fish species and highlights the effectiveness of Hg regulations on ocean apex predator Hg concentrations and overall seafood safety.

Microcystin-LR (MC-LR) and glyphosate (GLY) have been classified as a Group 2B and Group 2A carcinogens for humans, respectively, and frequently found in aquatic ecosystems. However, data on the potential hazard of MC-LR and GLY exposure to the fish gut are relatively scarce. In the current study, a subacute toxicity test of zebrafish exposed to MC-LR (35 μg L⁻¹) and GLY (3.5 mg L⁻¹), either alone or in combination was performed for 21 d. The results showed that MC-LR or/and GLY treatment reduced the mRNA levels of tight junction genes (claudin-5, occludin, and zonula occludens-1) and altered the levels of diamine oxidase and D-lactic, indicating increased intestinal permeability in zebrafish. Furthermore, MC-LR and/or GLY treatment remarkably increased the levels of intestinal IL-1β and IL-8 but decreased the levels of IL-10 and TGF-β, indicating that MC-LR and/or GLY exposure induced an inflammatory response in the fish gut. MC-LR and/or GLY exposure also activated superoxide dismutase and catalase, generally upregulated the levels of p53, bax, bcl-2, caspase-3, and caspase-9, downregulated the levels of caspase-8 and caused notable histological injury in the fish gut. Moreover, MC-LR and/or GLY exposure also significantly altered the microbial community in the zebrafish gut and the expression of miRNAs (miR-146a, miR-155, miR-16, miR-21, and miR-223). Chronic exposure to MC-LR and/or GLY can induce intestinal damage in zebrafish, and this study is the first to demonstrate an altered gut microbiome and miRNAs in the zebrafish gut after MC-LR and GLY exposure.

Tropospheric ozone is a highly oxidative pollutant with the potential to alter plant metabolism. The direct effects of ozone on plant phenotype may alter interactions with other organisms, such as pollinators, and, consequently, affect plant reproductive success. In a set of greenhouse experiments, we tested whether exposure of plants to a high level of ozone affected their phenological development, their attractiveness to four different pollinators (mason bees, honeybees, hoverflies and bumblebees) and, ultimately, their reproductive success. Exposure of plants to ozone accelerated flowering, particularly on plants that were growing in autumn, when light and temperature cues, that commonly promote flowering, were weaker. Simultaneously, there was a tendency for ozone-exposed plants to disinvest in vegetative growth. Plant exposure to ozone did not substantially affect pollinator preference, but bumblebees had a tendency to visit more flowers on ozone-exposed plants, an effect that was driven by the fact that these plants tended to have more open flowers, meaning a stronger attraction signal. Honeybees spent more time per flower on ozone-exposed plants than on control plants. Acceleration of flower production and the behavioural responses of pollinators to ozone-exposed plants resulted in retained reproductive fitness of plants pollinated by bumblebees, honeybees and mason bees, despite the negative effects of ozone on plant growth. Plants that were pollinated by hoverflies had a reduction in reproductive fitness in response to ozone. In a natural setting, acceleration of flowering by ozone might foster desynchronization between plant and pollinator activities. This can have a strong impact on plants with short flowering periods and on plants that, unlike wild mustard, lack compensatory mechanisms to cope with the absence of pollinator activity in the beginning of flowering.

Application of alternating current in electrocoagulation and activation of persulfate (AEC-PS) for the effective removal of humic acid (HA) from aqueous solution was evaluated. In order to optimize the removal efficiency HA by the AEC-PS process, several influencing parameters such as pH, reaction time, PS dose, current density (CD), concentration of NaCl, initial concentration of HA, and coexisting cations and anions influence were investigated. From the batch experiments, the highest HA removal efficiency obtained was 99.4 ± 0.5% at pH of 5, reaction time of 25 min, CD of 4.5 mA/cm², PS dose of 200 mg/L, and NaCl concentration of 0.75 g/L for an initial HA concentration of 30 mg/L. When CD increased from 1.25 to 4.5 mA/cm², the HA removal efficiency was improved from 88.8 ± 4.4% to 96.1 ± 1.5%. In addition, the type of coexisting cations and anions exerted a significant role, leading to a reduction in the removal efficiency of HA. To investigate the dominant free activated radical, radical scavengers such as tert-butyl alcohol and ethanol were employed. It was observed that both OH and SO₄⁻ radicals substantially contributed to the removal of HA, and the contribution of SO₄⁻ radical was higher than that of OH radical, suggesting that AEC-PS process could serve as a novel and effective treatment technique for the removal of organic matters from aqueous sources.

The frequency and duration of exposure to acrylamide (AA) from the environment and diet are associated with a range of adverse health effects. However, whether long-term AA exposure is related to diabetes mellitus (DM) remains unknown. Data from 3577 adults in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 and 2013–2016 aged ≥ 20 years was analysed. The main analyses applied multivariate logistic regression and restricted cubic spline models to investigate the associations between DM and AA haemoglobin biomarkers, including haemoglobin adducts of acrylamide and glycidamide (HbAA and HbGA), the sum of HbAA and HbGA (HbAA + HbGA), and the ratio of HbGA to HbAA (HbGA/HbAA) levels. After multivariable adjustment, the odds ratios (95% confidence intervals) for DM comparing the highest with the lowest AA haemoglobin biomarker quartiles were 0.71 (0.55, 0.93), 0.92 (0.71, 1.18), 0.80 (0.62, 1.03) and 1.95 (1.51, 2.51) for HbAA, HbGA, HbAA + HbGA and HbGA/HbAA, respectively. The restricted cubic spline model demonstrated that HbAA was linearly and inversely associated with risk of DM (P for trend = 0.013), while HbGA/HbAA was nonlinearly and positively associated with the prevalence of DM (P for trend <0.001). These results support for epidemiological evidence that the HbAA and HbGA/HbAA are significantly associated with DM. Further studies are warranted to infer the causal role of AA exposure in the prevalence of DM.

Parabens (PBs) are widely used as preservatives in food, pharmaceuticals and personal care products (PCPs). Due to their potential characteristics, similar to endocrine-disrupting compounds, their safety in our daily products and frequent exposure to human health have become public concerns. Nevertheless, little information is available about the occurrence of PBs in outdoor environments and their implications for human exposure. In this study, seven pairs of gas- and particle-phase air samples and 48 soil samples from Harbin City, China, were collected for the analysis of eight typical PBs (including methyl-paraben, ethyl-paraben, propyl-paraben, isopropyl-paraben, butyl-paraben, isobutyl-paraben, benzyl-paraben, and heptyl-paraben), which have been frequently selected as target compounds in previous studies. Concentrations of ∑₈PBs in outdoor air samples were 253–1540 pg/m³ with a median of 555 pg/m³. The results of the gas-particle partitioning indicated that PBs had not reached equilibrium between the gas phase and particle phase. Concentrations of ∑₈PBs in the soil samples were <LOQ-5530 ng/kg dw. Higher concentrations of PBs were observed in soils from commercial and residential areas with extensive anthropogenic activities. Based on the inhalation rate of air and ingestion rate of soil, the estimated daily intake (EDI) was calculated. The EDI values (EDIₐᵢᵣ + EDIₛₒᵢₗ) for male adults, female adults and children were comparable, with mean values of 2.74 × 10⁻², 3.21 × 10⁻² and 2.70 × 10⁻² ng/kg-bw/day, respectively. All EDIs were much lower than the daily acceptable intake, indicating lower health risk with PB occurrence in outdoor environments. Finally, the total EDI from all external exposure routes (outdoor air, indoor air, soil, indoor dust, foodstuffs, pharmaceuticals and PCPs) was calculated for the first time. The total EDI was not consistent with that of the internal exposure, which provided new insight into future studies for human exposure assessment.

Particulate matter (PM) had been associated with cardiotoxicity, while the mechanism of toxicity has yet to be elucidated, with mitochondria dysfunction as a potential candidate. To investigate the potential cardiotoxic effects of ambient PM exposure and assess the damage to cardiac mitochondria, C57/B6 mice were exposed to filtered air or real ambient PM for three or six weeks. Furthermore, to reveal the role of peroxisome proliferators-activated receptor alpha (PPAR alpha) in PM exposure induced cardiotoxicity/mitochondria damage, animals were also co-treated with PPAR alpha agonist WY 14,643 or PPAR alpha antagonist GW 6471. Cardiotoxicity was assessed with echocardiography and histopathology, while mitochondria damage was evaluated with mitochondria membrane potential measurement and transmission electron microscopy. Potential impacts of PM exposure to PPAR alpha signaling were detected with co-immunoprecipitation and western blotting. The results indicated that exposure to ambient PM exposure induced cardiotoxicity in C57/B6 mice, including altered cardiac functional parameters and morphology. Cardiac mitochondria damage is detected, in the form of compromised mitochondria membrane potential and morphology. Molecular investigations revealed disruption of PPAR alpha interaction with peroxisome proliferator-activated receptor gamma coactivator-1A (PGC-1a) as well as altered expression levels of PPAR alpha downstream genes. Co-treatment with WY 14,643 alleviated the observed toxicities, while co-treatment with GW 6471 had mixed results, exaggerating most cardiotoxicity and mitochondrial damage endpoints but alleviating some cardiac functional parameters. Interestingly, WY 14,643 and GW 6471 co-treatment seemed to exhibit similar regulative effects towards PPAR alpha signaling in animals exposed to PM. In conclusion, ambient PM exposure indeed induced cardiotoxicity in C57/B6 mice, in which cardiac mitochondria damage and disrupted PPAR alpha signaling are contributors.