Our study investigated occupational exposure to rare earth elements (REEs) in a major REE processing plant from North China by assessing both external exposure and internal exposure in the workers. An exposure group, including 50 workers in the processing plant, and a control group, including 50 workers from a liquor factory located 150 km away from the exposure group, were recruited in the study. Portable air sampler was employed to accurately measure individual exposure to the external environment, and the data demonstrating significantly higher contamination in the REE processing plant compared with the control group (i.e., 87.5 versus 0.49 μg/m³ of ΣREEs). Blood concentrations were also significantly higher in the exposure group (3.47 versus 2.24 μg/L of ΣREEs). However, the compositional profiles of REEs resembled between the exposure and control group in blood or air particles, indicating the influence of mining/processing activities on the surrounding regions. External exposure in the occupational environment appeared to significantly influence internal REE exposure in the REE processing workers. Some other sociodemographic and occupational factors, including the residence time and the type of work, could also influence occupational exposure to selected REEs. Our data clearly demonstrated the highly elevated REE contamination in both working environment and human bodies compared with the control subjects, raising the critical need for better assessing the health risks from occupational REE exposure and efficient management for occupational hazards.

Traffic exhaust is a main source of fine particulate matter (PM₂.₅) in cities. Heavy-duty diesel trucks (HDDTs), the primary mode of freight transport, contribute significantly to PM₂.₅, posing a great threat to public health. However, existing research based on dispersion models to simulate pollutant concentrations lacks high-spatiotemporal-resolution emission inventories of HDDTs as input data, and the public health effects of such emissions in different populations have not been thoroughly assessed. To fill this gap, we focused on Beijing as the research area and developed a high-resolution PM₂.₅ emission inventory for HDDTs based on Global Navigation Satellite System-equipped vehicle trajectory data. We then simulated the fine-scale spatial distribution of diesel-related PM₂.₅ and assessed the population exposure by integrating the dispersion model and population distributions. Further, we quantified the mortality attributable to noncommunicable diseases (NCDs) plus lower respiratory infections (LRIs) related to PM₂.₅ emissions from HDDTs. Results showed that 3.3% of Beijing people lived in areas with high PM₂.₅ HDDT emissions, which were near intercity highways. Furthermore, the estimated number of NCD + LRI annual premature deaths attributed to PM₂.₅ HDDT emissions in Beijing was 339 (95% CI: 276–401). The NCD + LRI mortality increased with age, and deaths were more frequent in males than females. Our results aid the identification of HDDT PM₂.₅ emission exposure hotspots for the formulation of effective mitigation measures and provide important insights into the adverse health impacts of HDDT emissions.

Metal-based nanoparticles (NPs) are considered detrimental to aquatic organisms due to their potential accumulation. However, little is known about the mechanisms underlying these effects and their species-specificity. Here we used stable silver (Ag) NPs (20 nm, from 10 to 500 μg/L) with a low dissolution rate (≤2.4%) to study the bioaccumulation and biological impacts in two freshwater gastropods: Lymnaea stagnalis and Planorbarius corneus. No mortality was detected during the experiments. Ag bioaccumulation showed a dose-related increase with an enhanced concentration in both species after 7d exposure. L. stagnalis displayed a higher accumulation for AgNPs than P. corneus (e.g., up to 18- and 15-fold in hepatopancreas and hemolymph, respectively) which could be due to the more active L. stagnalis having greater contact with suspended AgNPs. Furthermore, the hepatopancreas and stomach were preferred organs for bioaccumulation compared to the kidney, mantle and foot. Regarding biological responses, the hemolymph rather than hepatopancreas appeared more susceptible to oxidative stress elicited by AgNPs, as shown by significantly increasing lipid peroxidation (i.e., formation of malondialdehyde). Neurotoxicity was detected in L. stagnalis when exposed to high concentrations (500 μg/L). Comparison with impacts elicited by dissolved Ag revealed that the effects observed on AgNPs exposure were mainly attributable to NPs. These results highlighted the relationship between the physiological traits, bioaccumulation, and toxicity responses of these two species to AgNPs and demonstrated the necessity of species-specificity considerations when assessing the toxicity of NPs.

Although it is a probable human carcinogen, propylene oxide is widely applied in industry and daily life. However, data on neurodevelopmental effects of propylene oxide exposure among children are extremely limited. We aimed to determine the urinary concentrations of propylene oxide metabolite among school-aged children and evaluate the potential association of propylene oxide exposure with risk of dyslexia. A total of 355 dyslexic children and 390 controls were recruited from three cities (Jining, Wuhan, and Hangzhou) in China, between 2017 and 2020. Urinary N-acetyl-S-(2-hydroxypropyl)-L-cysteine (i.e., 2-hydroxypropyl mercapturic acid; 2-HPMA) was measured as the biomarker of propylene oxide exposure. The detection frequency of 2-HPMA was 100%. After adjusting for potential confounders, the odds ratio (OR) for dyslexia per 2-fold increase in urinary 2-HPMA was 1.19 [95% confidence interval (95% CI): 1.01, 1.40, P = 0.042]. Compared with the lowest quartile of urinary 2-HPMA concentrations, children with the highest quartile of 2-HPMA had a 1.63-fold (95% CI: 1.03, 2.56, P = 0.036) significantly increased risk of dyslexia, with a dose-response relationship (P-trend = 0.047). This study provides epidemiological data on the potential association between propylene oxide exposure and the risk of dyslexia in children. Further studies are warranted to confirm the findings and reveal the underlying biological mechanisms.

This study investigates a comparison between the photocatalytic action of two nanocomposites (TiO₂ and TiO₂(Ag) doped) on the degradation of phenol from water. The nanocomposites were synthesized by the UV photo-reduction process to get a silver metal loading of 0.25, 0.5, 0.75, and 1% (w/w). In addition to this, Eriochrome Cyanine Red (ECR) and Eosin Yellow (EY) both anionic dyes were used for sensitization of Ag-doped TiO₂ photo-catalyst such as TiO₂(Ag)ECR and TiO₂(Ag)EY. The TiO₂(Ag-1.0)EY photo-catalyst indicated higher absorbance compared to the TiO₂(Ag-1.0)ECR in the 400–700 nm range (visible range). The degradation of phenol was tested by varying the pH, silver loading and catalyst dosage. The maximum degradation of phenol was 98% in 180 min at pH 7 in presence of 1% (w/w) silver loading with 0.5 gL⁻¹ dosage of photo-catalyst TiO₂(Ag-1.0)EY. At this condition, the reduction in the phenol concentration was noticed from 20 mg/L to 0.4 mg/L.

China has been in a rapid development period in recent decades, the mass production and use of chemical industrial products and pesticides have resulted in a large amount of pollutants in the environment. These pollutants enter the human body through environmental exposure and dietary intake, causing adverse health effects. Although many of them have been banned and restricted in the production and use in China, these pollutants still remain in the human body due to their high persistence and strong bioaccumulation. In this review, we aim to reveal the accumulation levels and profiles, as well as the temporal and spatial distribution of common chemical pollutants including chlorinated paraffins (CPs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers, organophosphorus flame retardants (OPFRs), new halogenated flame retardants (NHFRs), polychlorinated biphenyls, phthalic acid esters, perfluorinated compounds, bisphenols, organophosphorus pesticides and pyrethroid insecticides in the blood (including whole blood, serum and plasma) of Chinese adults by extracting 93 related studies published from 1990 to 2021. Results have shown that CPs, OCPs and PAHs were the main pollutants in China, the levels of short-chain chlorinated paraffin, p,p'-DDE and phenanthrene in blood even reached 11,060.58, 740.41 and 498.28 ng/g lipid respectively. Under the strict control of pollutants in China, the levels of most pollutants have been on a downward trend except for perfluoro octanoate and perfluoro nonanoate. Besides, OPFRs, NHFRs and PAHs may have a potential upward trend, requiring further research and observation. As for spatial distribution, East China (Bohai Bay and Yangtze River Delta) and South China (Pearl River Delta) were the major polluted regions due to their fast development of industry and agriculture.

Herein, magnetic porous pinecone-derived hydrochar (MPHCMW) co-activated by KHCO₃ and K₂FeO₄ through one-step microwave-assisted pyrolysis was innovatively synthesized for hexavalent chromium (Cr(VI)) and anthracene (ANT) removal from water. The analyses of characterization consequences and co-activation mechanisms not merely proved the high specific surface area (703.97 m²/g) and remarkable microporous structures of MPHCMW caused by the synergistic chemical activation of KHCO₃ and K₂FeO₄, but also testified successful loading of Fe⁰ and Fe₃O₄ on MPHCMW by the process of carbothermal reduction between K₂FeO₄ and carbon matrix of hydrochar. The resultant MPHCMW possessed pH-dependence for Cr(VI), while adsorption for ANT was hardly impacted by the pH of solution. Moreover, the adsorption processes of MPHCMW could attain equilibrium within 60 min for Cr(VI) and 30 min for ANT with multiple kinetics, and the corresponding adsorption capacity for Cr(VI) and ANT was 128.15 and 60.70 mg/g, respectively. Additionally, the adsorption percentages of MPBCMW for Cr(VI)/ANT was maintained at 87.87/82.64% after three times of adsorption-desorption cycles. Furthermore, pore filling, complexation, electrostatic interaction, reduction and ion exchange were testified to enhance the removal of Cr(VI), while the ANT removal was achieved via π-π stacking, complexation, pore filling and hydrogen bonding force.

Bioremediation technologies have demonstrated significant success on biological quality recovery of hydrocarbon contaminated soils, employing techniques among which composting and vermiremediation stand out. The aim of this study was to evaluate the efficiency of these processes to remediate diesel-contaminated soil, employing local organic materials and earthworms. During the initial composting stage (75 days), the substrate was made up using contaminated soil, lombricompost, rice hulls and wheat stubbles (60:20:15:5% w/w). Diesel concentration in the contaminated substrate was about 5 g kg⁻¹, equivalent to a Total Petroleum Hidrocarbons (TPH) experimental concentration of 3425 ± 50 mg kg⁻¹. During the later vermiremediation stage (60 days), the earthworm species Eisenia fetida and Amynthas morrisi were evaluated for their hydrocarbon degradation capacity. Physicochemical and biological assays were measured at different times of each stage and ecotoxicity assays were performed at the end of the experiments. TPH concentration reduced 10.91% after composting and from 45.2 to 60.81% in the different treatments after vermiremediation. Compared with TPH degradation in the treatment without earthworms (16.05%), results indicate that earthworms, along with indigenous microorganisms, accelerate the remediation process. Vermiremediation treatments did not present phytotoxicity and reflected high substrate maturity values (>80% Germination Index) although toxic effects were observed due to E. fetida and A morrisi exposure to diesel. Vermiremediation was an efficient technology for the recovery of substrate biological quality after diesel contamination in a short period. The addition of organic materials and suitable food sources aided earthworm subsistence, promoted the decontamination process and improved the substrate quality for future productive applications.

Under the climate change context, warming Southern Ocean waters may allow mercury (Hg) to become more bioavailable to the Antarctic marine food web (i.e., ice-stored Hg release and higher methylation rates by microorganisms), whose biomagnification processes are poorly documented. Biomagnification of Hg in the food web of the Antarctic Peninsula, one of the world's fastest-warming regions, was examined using carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotope ratios for estimating feeding habitat and trophic levels, respectively. The stable isotope signatures and total Hg (T-Hg) concentrations were measured in Antarctic krill Euphausia superba and several Antarctic predator species, including seabirds (gentoo penguins Pygoscelis papua, chinstrap penguins Pygoscelis antarcticus, brown skuas Stercorarius antarcticus, kelp gulls Larus dominicanus, southern giant petrels Macronectes giganteus) and marine mammals (southern elephant seals Mirounga leonina). Significant differences in δ¹³C values among species were noted with a great overlap between seabird species and M. leonina. As expected, significant differences in δ¹⁵N values among species were found due to interspecific variations in diet-related to their trophic position within the marine food web. The lowest Hg concentrations were registered in E. superba (0.007 ± 0.008 μg g⁻¹) and the highest values in M. giganteus (12.090 ± 14.177 μg g⁻¹). Additionally, a significant positive relationship was found between Hg concentrations and trophic levels (reflected by δ¹⁵N values), biomagnifying nearly 2 times its concentrations at each level. Our results support that trophic interaction is the major pathway for Hg biomagnification in Southern Ocean ecosystems and warn about an increase in the effects of Hg on long–lived (and high trophic level) Antarctic predators under climate change in the future.

Understanding the processes that underlay an ecological disaster represents a major scientific challenge. Here, we investigated phytoplankton and zooplankton community changes before and during a fauna mass kill in a European protected wetland. Evidence on gradual development and collapse of harmful phytoplankton blooms, allowed us to delineate the biotic and abiotic interactions that led to this ecological disaster. Before the mass fauna kill, mixed blooms of known harmful cyanobacteria and the killer alga Prymnesium parvum altered biomass flow and minimized zooplankton resource use efficiency. These blooms collapsed under high nutrient concentrations and inhibitory ammonia levels, with low phytoplankton biomass leading to a dramatic drop in photosynthetic oxygenation and a shift to a heterotrophic ecosystem phase. Along with the phytoplankton collapse, extremely high numbers of red planktonic crustaceans-Daphnia magna, visible through satellite images, indicated low oxygen conditions as well as a decrease or absence of fish predation pressure. Our findings provide clear evidence that the mass episode of fish and birds kill resulted through severe changes in phytoplankton and zooplankton dynamics, and the alternation on key abiotic conditions. Our study highlights that plankton-related ecosystem functions mirror the accumulated heavy anthropogenic impacts on freshwaters and could reflect a failure in conservation and restoration measures.