Previous studies indicated that exposure to air pollution was associated with the progress of atherosclerosis, but evidence is very limited in China and even in the world. This study aims to assess the associations of long-term exposures to air pollution and greenness with the occurrence of carotid plaque. Participants of this cohort study were urban residents and office workers who visited Hebei General Hospital for routine physical examination annually from September 2016 through to December 2018. Eligible participants were people diagnosed the absence of carotid plaque clinically at their first hospital visit and were followed up at their second or third hospital visit. Exposure to particulate matter with aerodynamic diameter less than 2.5 μm (PM₂.₅), nitrogen dioxide (NO₂) and ozone (O₃) were estimated using an inverse distance weighted (IDW) method. The level of greenness was assessed using the Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). The associations were evaluated using Cox proportional hazards regression models. Among 4,137 participants, 575 showed the occurrence of carotid plaque during the follow-up period. After controlling for potential confounders, the hazard ratios (HRs) and 95% confidence intervals (95%CIs) of carotid plaque associated with per interquartile range (IQR) increase in PM₂.₅, NO₂, and O₃ were 1.78 (1.55, 2.03), 1.32 (1.14, 1.53) and 1.99 (1.71, 2.31), respectively. Increased EVI and NDVI were significantly associated with lower risk of carotid plaque [HR (and 95%CI): 0.84 (0.77, 0.93) and 0.87 (0.80, 0.94)]. PM₂.₅ significantly mediated 80.47% or 93.00% of the estimated association between EVI or NDVI and carotid plaque. In light of the significant associations between air pollution, greenness and carotid plaque in this study, continued efforts are needed to curb air pollution and plan more green space considering their effects on vascular disease.

Management of water-quality in a river ecosystem needs to be focused on susceptible regions to eutrophication based on proper measurements. The stress–response relationships between nutrients and primary productivity of phytoplankton allow the derivation of ecologically acceptable thresholds of stressors under field conditions. However, spatio-temporal variations in heterogeneous environmental conditions have hindered the development of locally applicable criteria. To address these issues, we utilized a combination of a geographically specialized artificial neural network (Geo-SOM, geo-self-organizing map) and linear mixed-effect models (LMMs). The model was applied to a 24-month dataset of 54 stations that spanned a wide spatial gradient in the Nakdong River basin. The Geo-SOM classified 1286 observations in the basin into 13 clusters that were regionally and seasonally distinct. Inclusion of the random effects of Geo-SOM clustering improved the performance of each LMM, which suggests that there were significant spatio-temporal variations in the Chla–stressor relationships. These variations arise owing to differences in background seasonality and the effects of local pollutant variables and land-use patterns. Among the 16 environmental variables, the major stressors for Chla were total phosphate (TP) as a nutrient and biological oxygen demand (BOD) as a non-nutrient according to the results of both Geo-SOM and LMM analyses. Based on LMMs with the random effect of the Geo-SOM clusters on the intercept and the slope, we can propose recommended thresholds for TP (18.5 μg L⁻¹) and BOD (1.6 mg L⁻¹) in the Nakdong River. The combined method of LMM and Geo-SOM will be useful in guiding appropriate local water-quality-management strategies and in the global development of large-scale nutrient criteria.

The occurrence of organochlorine pesticides (OCPs) used decades ago for vector control in urban areas is still reported as a threat to human health. Pyrethroids emerged as a replacement for OCPs in sanitary campaigns and are currently the main insecticides used for vector control worldwide, with prominent use as agricultural and household insecticides, for veterinary and gardening purposes, and as wood preservative. This study aimed to assess the occurrence, seasonal variation, and potential sources of pyrethroids in ambient air of two urban regions of Southeastern Brazil, along with the potential health risks to local populations via inhalation exposure. Pyrethroids were sampled by polyurethane foam passive air samplers and their concentrations were determined by gas chromatography coupled with electron capture negative ionization mass spectrometry (GC/ECNI-MS). Atmospheric pyrethroid concentrations (hereinafter reported in pg m⁻³) were considerably higher than those reported by previous studies worldwide. Cypermethrin (median: 2446; range: 461–15 125) and permethrin (655; 19–10 328) accounted for 95% of the total measured pyrethroids in ambient air. The remaining fraction comprised smaller amounts of bifenthrin (46; <limit of detection (LOD)–5171), deltamethrin (58; <LOD–564), phenothrin (7; <LOD–22) and fenvalerate (0.3; <LOD–3). Bifenthrin, deltamethrin and permethrin were linked to local sources, while cypermethrin, fenvalerate and phenothrin had more prominent regional contributions. In broad terms, most pyrethroids showed no clear seasonal trend. The concentrations and hazard quotients (HQs) showed the following order of occurrence and magnitude: urban > urban-industrial > background areas. HQs increased with decreasing age group, but deterministic and probabilistic estimates did not identify direct health risks for any group. Nevertheless, since only inhalation exposure was considered in this work, other pathways should be investigated to provide a more comprehensive risk assessment of the human exposure to pyrethroids.

Both submerged macrophytes (SMs) and artificial macrophytes (AMs) have been widely used to improve water quality in eutrophic water. However, in heavily eutrophic aquatic ecosystems, the purification function of SMs is often restricted by the poor growth state due to competition from algae, while the purification function of AMs is often restricted by the limited carbon source supply for biofilm microbes attached to the AM surface. The objective of this study was to develop a new strategy to increase pollutant removal efficiency (RE) by combining the use of SMs and AMs. Pilot-scale microcosms, including treatments with both SMs and AMs (S&A), only SMs (SO) and only AMs (AO), were established to identify the performance of the new strategy. The results suggest that treatment S&A obtained REs of 88.9% for total nitrogen (TN) and 48.1% for chemical oxygen demand (COD); as comparison, treatments SO and AO obtained REs of 77.4% and 81.2% for TN and REs of −13.7% and 39.0% for COD, respectively. Compared with SO, the S&A treatment benefited SM growth in biomass, leaf chlorophyll concentration and root activity by inhibiting algae growth. In addition, compared with treatment AO, S&A increased the biofilm microbial biomass and the relative abundance of nitrifiers of families Nitrosomonadaceae and Nitrospira attached to AM surfaces. Therefore, by the mutual promotion of SMs and biofilms on AMs, the synergic application of SMs and AMs is a useful strategy for improving TN and COD REs in eutrophic water bodies such as rivers and constructed wetlands.A strategy was developed to increase nitrogen and COD removal in eutrophic water by the mutual promotion of submerged macrophytes and biofilms on artificial macrophytes.

The environmental-friendly photocatalytic process with a magnetic catalyst CoFe₂O₄/TiO₂ mediated by solar light for ibuprofen (IBP) degradation in pure water, wastewater effluent and artificial seawater was investigated systematically. The study aims to reveal the efficiency, the mechanism and toxicity evolution during IBP degradation. Hydroxyl radicals and photo-hole (h⁺) were found to contribute to the IBP decay. The presence of SO₄²⁻ showed no significant effect, while NO₃⁻ accelerated the photodegradation, and other anions including HCO₃⁻, Cl⁻, F⁻, and Br⁻ showed significant inhibition. The removal efficiency was significantly elevated with the addition of peroxymonosulfate (PMS) or persulfate (PS) ([Oxidant]₀:[IBP]₀ = 0.4–4), with reaction rate of 5.3–13.1 and 1.3–2.9 times as high as the control group, respectively. However, the reaction was slowed down with the introduction of H₂O₂. A mathematic model was employed to describe the effect of ferrate, high concentration or stepwise addition of ferrate was suggested to play a positive role in IBP photodegradation. Thirteen transformation products were identified and five of them were newly reported. The degradation pathways including hydroxylation, the benzene ring opening and the oxidation of carbon were proposed. IBP can be efficiently removed when spiked in wastewater and seawater despite the decreased degradation rate by 41% and 56%, respectively. Compared to the IBP removal, mineralization was relatively lower. The adverse effect of the parent compound IBP to the green algae Chlorella vulgaris was gradually eliminated with the decomposition of IBP. The transformation product C178a which possibly posed toxicity to rotifers Brachionus calyciflorus can also be efficiently removed, indicating that the photocatalysis process is effective in IBP removal, mineralization and toxicity elimination.

Hooghly River (HR), the other name used for the lower stretch of River Ganga, is a prime freshwater source in the eastern part of India. However HR has been evidenced with a variety of emerging organic pollutants (EOPs) in the recent past. Given the extensive use of plasticizers and additive in plastic products, we have investigated seven plasticizers and bisphenol A (BPA) in the surface and storm-water of HR up to the tip of the Bay of Bengal. Further using a previously published sediment data we have estimated the fluxes for the aforementioned EOPs. Surface water and storm-water concentrations of seven plasticizers varied between 92.62 and 770 ng/L (176.1 ± 104.8; Avg ± SD) and 120.9–781.5 ng/L (355.2 ± 232.5), respectively. BPA varied between 43 and 8800 ng/L (658.3 ng/L ± 1760) and 117.9–2147 ng/L (459.3 ± 620.2) in surface and storm-water, respectively. With the increase in salinity, a decreasing trend for bis-(2-ethylhexyl) phthalate (DEHP) was evidenced. However, concentration of BPA increased with the increase in salinity. Significant and strong correlation between DEHP and BPA (R² = 0.6; p < 0.01) in the suburban corridor might have resulted from sludge disposal of the scrap recycling activities. Using site-specific principal component analysis, unregulated disposal of plastic waste, particularly from such industrial belts and tourist spots were identified as the possible point sources for plasticizers and BPA in this region. Net diffusive flux based on fugacity fraction showed a trend depending on the pollutant’s aqueous solubility and partition coefficient. However, transfer tendency from water to sediment was noticed in the sites having point source. Estimated ecotoxicological risk posed by BPA was higher for edible fishes and for lower order organisms, PAEs was the major contributor.

Bifenazate is a novel acaricide for selective foliar spraying and is widely used to control mites in agricultural production. However, its toxicity to aquatic organisms is unknown. Here, a zebrafish model was used to study bifenazate toxicity to aquatic organisms. Exposure to bifenazate was found to cause severe cardiotoxicity in zebrafish embryos, along with disorders in the gene expression related to heart development. Bifenazate also caused oxidative stress. Cardiotoxicity caused by bifenazate was partially rescued by astaxanthin (an antioxidant), accompanied by cardiac genes and oxidative stress-related indicators becoming normalized. Our results showed that exposure to bifenazate can significantly change the ATPase activity and gene expression levels of the calcium signaling pathway. These led to heart failure, in which the blood accumulated outside the heart without entering it, eventually leading to death. The results indicated that bifenazate exposure caused cardiotoxicity in zebrafish embryos through the induction of oxidative stress and inhibition of the calcium signaling pathway.

Wetland snakes, as top predators, are becoming globally recognised as bioindicators of wetland contamination. Livers are the traditional test organ for contaminant exposure in organisms, but research is moving towards a preference for non-lethal tissue sampling. Snake scales can be used as an indicator of exposure, as many metals bind to the keratin. We used laser ablation with inductively coupled plasma-atomic emission spectroscopy and mass spectrometry (LA-ICP-MS) to quantify the concentrations of 19 metals and metalloids (collectively referred to ‘metals’ hereafter) in Western tiger snake (Notechis scutatus occidentalis) scales from four wetlands along an urban gradient, and compared them to concentrations measured in captive tiger snake scales. We conducted repeat measures to determine the concentration accuracy of each metal using LA-ICP-MS. Concentrations in wild Western tiger snake scales were significantly higher than in reference tiger snake scales for most metals analysed, suggesting accumulation from environmental exposure. We compared the scale concentrations to sediment concentrations of sampled wetlands, and found inter-site differences between mean concentrations of metals in scales parallel patterns recorded from sediment. Four metals (Mn, As, Se, Sb) had strong positive correlations with liver tissue contents suggesting scale concentrations can be used to infer internal concentrations. By screening for a larger suite of metals than we could using traditional digestive methods, we identified additional metals (Ti, V, Sr, Cs, Tl, Th, U) that may be accumulating to levels of concern in tiger snakes in Perth, Western Australia. This research has progressed the use of LA-ICP-MS for quantifying a suite of metals available in snake scales, and highlights the significance of using wetland snake scales as a non-lethal indicator of environmental contamination.

Chemical pollutants, such as pesticides, often leach into aquatic environments and impact non-target organisms. Marine invertebrates have complex life cycles with multiple life-history stages. Exposure to pesticides during one life-history stage potentially influences subsequent stages; a process known as a carry-over effect. Here, we investigated carry-over effects on the jellyfish Aurelia coerulea. We exposed polyps to individual and combined concentrations of atrazine (2.5 μg/L) and chlorpyrifos (0.04 μg/L) for four weeks, after which they were induced to strobilate. The resultant ephyrae were then redistributed and exposed to either the same conditions as their parent-polyps or to filtered seawater to track potential carry-over effects. The percentage of deformities, ephyrae size, pulsation and respiration rates, as well as the metabolic profile of the ephyrae, were measured. We detected a subtle carry-over effect in two metabolites, acetoacetate and glycerophosphocholine, which are precursors of the neurotransmitter acetylcholine, important for energy metabolism and osmoregulation of the ephyrae. Although these carry-over effects were not reflected in the other response variables in the short-term, a persistent reduction of these two metabolites could have negative physiological consequences on A. coerulea jellyfish in the long-term. Our results highlight the importance of considering more than one life-history stage in ecotoxicology, and measuring a range of variables with different sensitivities to detect sub-lethal effects caused by anthropogenic stressors. Furthermore, since we identified few effects when using pesticides concentrations corresponding to Australian water quality guidelines, we suggest that future studies consider concentrations detected in the environment, which are higher than the water quality guidelines, to obtain a more realistic scenario by possible risk from pesticide exposure.

Enhancing and investigating the photocatalytic activity over composites for new models remains a challenge. Here, an emerging S-scheme photocatalyst composed of 2D/0D g-C₃N₄ nanosheets-assisted SnO₂ nanoparticles (g-C₃N₄/SnO₂) is successfully synthesized and used for degrading nitrogen oxide (NO), which causes negative impacts on the environment. A wide range of characterization techniques confirms the successful synthesis of SnO₂ nanoparticles, g-C₃N₄ nanosheets, and 2D/0D g-C₃N₄/SnO₂ S-scheme photocatalysts via hydrothermal and annealing processes. Besides, the visible-light response is confirmed by optical analysis. The S-scheme charge transfer was elucidated by Density-Functional Theory (DFT) calculation, trapping experiments, and electron spin resonance (ESR). We found that intrinsic oxygen vacancies of SnO₂ nanoparticles and S-scheme charge transfer addressed the limitation of other heterojunction types. It is notable that compared pure SnO₂ nanoparticles and g-C₃N₄, g-C₃N₄/SnO₂ offered the best photocatalytic NO degradation and photostability under visible light with the removal of more than 40% NO at 500 ppb throughout the experiment. Benefiting from the unique structural features, the new generation architectural structure of S-scheme heterojunction exhibited potential photocatalytic activity and it would simultaneously act more promising for environmental treatment in the coming years.