Artemisinin sustained-release microspheres (ASMs) with long-term inhibition effects (> 40 days) on harmful freshwater bloom-forming cyanobacteria have been found in previous studies, but the inhibition mechanism is not completely clear. In the present study, we examined the growth effect of ASMs on Microcystis aeruginosa (M. aeruginosa) cells at different physiological stages. Growth experiments indicated that M. aeruginosa of different initial densities could be inhibited immediately and chlorophyll-a content both showed significant decreases following exposure of cyanobacteria to optimal dosage of ASMs for 20 days. The algicidal mechanism of ASMs was tested through a suite of physiological parameters (membrane permeability, antioxidant enzymes activity, and lipid peroxidation). The rise of cell membrane permeability indices (intracellular protein, nucleic acid contents, and conductivity) showed that the cellular membrane structure of M. aeruginosa was attacked by ASMs directly causing the leakage of cytoplasm. Antioxidant enzyme activity was a sensitive indicator of the impacts of ASMs which showed a significant downtrend after a few days. ASMs caused a great increase in •O₂⁻ and malondialdehyde (MDA) level of the algal cells which indicated the increase in lipid peroxidation of M. aeruginosa. Irreversible membrane damage induced by ASMs via the oxidation of ROS may be an important factor responsible for the algicidal mechanism of ASMs on M. aeruginosa cells. The application of ASMs might provide a new direction to control M. aeruginosa, especially before the exponential phase according to the optimal economy and inhibition effect. Graphical abstract

The purpose of this study was to investigate, for the first time, the effects of Bifenthrin (Bif) chronic exposure on plasmatic and aortic lipid parameters disturbance and their pro-atherogenic possibility in Wistar rats. The ameliorative role of vitamin E (Vit E) and selenium (Se) were also targeted. Thus, rats were treated by gastric gavage with combination of Vit E (100 mg/kg/bw) and Se (0.25 mg/kg/bw) in alone and co-treated groups for 90 days. Apart from control and Vit E-Se groups, all the groups were subjected to Bif (3 mg/kg, via gavage) toxicity. Results showed that Bif increased markedly plasmatic and aortic total cholesterol, LDL-cholesterol, native LDL-apoB-100, and oxidized-LDL, compared to the control. Moreover, Bif treatment significantly increased the plasmatic levels of the pro-inflammatory cytokines TNF-α, IL-2, and IL-6. In addition, the densitometric quantification of protein bands showed that the amount of hepatic native LDL-receptor protein decreased significantly in the intoxicated rats compared to the control group. The expression of arterial LDL receptors (LDLRs) and scavenger receptors (CD36) was amplified owing to Bif toxicity. This harmful effect was confirmed by histological study using Oil-Red-O staining. Owing to their antioxidant capacities, Vit E and Se have maintained all the changes in plasma and aorta lipids and prevented the pro-atherogenic effect observed in Bif-treated animals.

Coal mining causes serious ecological and environmental damage. The crushed gangue is backfilled into underground goaf, which not only inhibits mining-induced subsidence but also reduces accumulation of waste on the ground: however, the effects of backfilling with gangue backfill materials in goaf are affected by a combination of multiple factors. To predict compression-induced deformation (CID) of gangue backfill materials, key factors influencing compression and deformation characteristics of gangue backfill materials in an underground confined space (lithology, particle size distribution, lateral stress and lateral loading times) were determined. Moreover, two key factors, namely, lithology and particle size distribution of gangue backfill materials, were quantified. Based on orthogonal test design, the compression characteristics of gangue backfill materials were measured under different stress levels and coupling effects of the four key factors by utilising a self-made bidirectional loading test system for bulk materials. Furthermore, through regression, the relationships of the four key factors and axial strain were determined as well as undetermined parameters in axial stress-axial strain equations and axial stress. Based on this, an equation for predicting stress-strain relationship during compression-induced deformation of gangue backfill materials under multi-factor coupling effects was established. Comparison with the orthogonal test results shows that this equation can predict compression-induced deformation of gangue backfill materials in goaf. This is beneficial to providing a basis for predicting strata movement and surface subsidence and guidance for designing backfilling process, thus protecting the surface environment.

The present study assessed the exposure to methylparaben (MP) and propylparaben (PP) from antiperspirants in serum of 24 women aged 20–30 years old and an in vitro skin assay. An effective liquid chromatography–tandem mass spectrometry method for the determination of MP and PP levels in serum was developed and validated in the range of 10–100 μg/L; the method was fast, simple, sensitive, linear, precise, and accurate. In addition, a simple and rapid liquid chromatography–ultraviolet detection method for the determination of MP and PP levels in antiperspirants was developed and validated in the range of 2–26 mg/L, which presented satisfactory linearity, precision, and accuracy. Using these two methods, 20 commercial antiperspirants were evaluated, and only three showed MP and PP in the formulation. The antiperspirant containing 0.2% and 0.1% w/w MP and PP, respectively, was given to the volunteers, to estimate the internal dose, and submitted to a pig ear skin permeation assay in Franz diffusion cells, presenting a permeation flux of 32% for MP and 71% for PP. In this assay, both MP and PP permeated the skin; however, there was no correlation between antiperspirant use and paraben serum concentration in the volunteers. Graphical abstract

Landfill stabilization contributes to the safe operation and maintenance of landfills. This study used a simulated aerobic bioreactor landfill to investigate the impact of different compaction densities on its stabilization to provide a basis for optimal parameter selection during landfill design. Samples of municipal solid waste were tested with compaction densities of 450, 500, 550, 600, and 650 kg/m³ during the experiment. The optimum compaction density was obtained by periodically monitoring the temperature of the waste pile, the water quality of leachate, and the composition of the waste. The impacts of waste compaction density on waste pile temperature and leachate were investigated and coupled with the analysis of waste composition to discuss the possible reaction mechanism. Results showed that the most complete waste degradation occurred at 550 kg/m³ compaction density, which was effective at accelerating stabilization of the simulated aerobic bioreactor landfill. Limitations of the experiment are given to lay foundations for further study.

This work investigates the dynamic heterogeneous causal links among financial development, construction industry, energy use, and environmental quality across the development levels, for 30 Chinese provinces during the period 2001–2016. For this purpose, a model of environmental quality has been constructed introducing the financial development and construction industry as endogenous factors. A Pedroni’s cointegration is employed and found the long-run cointegrating mechanism among the variables of interest. The dynamic common correlated effects mean group approach (DCCEMGA) is adopted to estimate the impact elasticities. Moreover, for robustness check, a sensitivity analysis is conducted employing common correlated effects mean group approach (CCEMGA). The main results are first, a two-way positive causal bridge is existent between gross domestic product (GDP) and energy use, construction industry and GDP, and financial development and GDP. In terms of the contribution of the construction industry to economic performance, construction industry-driven growth acceleration impact is observed. Second, a one-way positive causal link is identified running from financial development (both the banking sector and stock market) to the construction industry and is termed as finance-driven construction promotion effect. Also, a one-sided positive causal connection is operating from financial development and construction industry to energy use and carbon dioxide emissions. Finally, a standard environmental Kuznets curve (EKC), financial development-augmented EKC, and construction industry-augmented EKC hypotheses are found valid in the whole country and eastern region of China. Based on empirics, a regional heterogeneity has been observed in terms of the degree of impact and statistical significance while comparing the regional panels. The sensitivity analysis proved the empirical results to be robust and reliable. Moreover, based on the findings, policy recommendations are documented. Graphical abstract

The long-term distribution of in situ optically active substances (OAS), accuracy assessment of satellite retrieved chlorophyll-a (chl-a) and its long-term trend has been carried out at a coastal site of the north-western Bay of Bengal. The temporal distribution of chl-a, total suspended matter (TSM) and absorption due to coloured dissolved organic matter at 440 nm (aCDOM440) discerned a common peak during southwest monsoon season (August–October). Chl-a also showed a prominent peak during pre-southwest monsoon period (March–April). The spatial variability of TSM and aCDOM440 was maximum during southwest monsoon, whereas in the case of chl-a, it was during pre-southwest monsoon. The accuracy assessment of chl-a retrieved from Moderate Resolution Imaging Spectroradiometer-Aqua (MODISA), Ocean Colour Monitor-2 (OCM-2) and Visible Infrared Imager Radiometer Suite (VIIRS) showed overestimation in nearshore waters. The error in satellite measurement of chl-a was within the range of 33 to 51%. The chl-a retrieved from MODISA was most accurate as indicated by statistical analysis. The long-term trend in satellite chl-a clearly indicated bi-modal distribution with a primary peak during pre-southwest monsoon attributed to recurrent phytoplankton bloom that was mostly confined to nearshore waters. Whereas, the secondary peak in chl-a, during the end of southwest monsoon, spreads far offshore.

Pot experiment was conducted to evaluate the effect of two types of biochar (2% (w/w)), Pennisetum sinese Roxb biochar (PB) and coffee grounds biochar (CB), combined with iron fertilizer (1.3 g kg⁻¹ Fe) on the growth, quality, Cd/Pb accumulation in watercress, soil physicochemical properties, soil fertility, soil enzyme activities, and fraction distribution of Cd/Pb in soil. The results showed that the two types of biochar combined with iron fertilizer (BC-Fe) amendments could increase the shoot height, root length, plant biomass, soluble sugar and soluble protein of watercress, soil pH value, soil organic matter (SOM), ammonium nitrogen (NH₄⁺-N), available phosphorus, and available potassium. CB-Fe amendment enhanced soil urease, sucrose, and catalase activities, while PB-Fe amendment only enhanced soil urease activity among the three enzymes. The two BC-Fe amendments decreased exchangeable-Cd/Pb and reducible-Cd/Pb concentrations, while enhanced oxidizable-Cd/Pb and residual-Cd/Pb concentrations. Furthermore, the two BC-Fe amendments decreased significantly Cd and Pb accumulation in watercress root and shoot. The reduction rate for Cd and Pb in shoot by 42.9%, 20.0%, and 68.2%, 58.4% under PB-Fe and by 38.1%, 20%, and 62.5%, 48.8% under CB-Fe, respectively, for the first crop and the second crop. In conclusion, BC-Fe amendment could improve soil physicochemical properties and soil fertility, promote Cd and Pb transfer to the stable form, thus, reduce the bioavailability and mobility of Cd and Pb, and further, decrease Cd and Pb ecotoxicity and its accumulation in watercress and improve watercress quality.

Dechlorane plus (DP) is a chlorinated flame retardant with high production volume (HPV) and is widely used in our daily necessities. In the present study, a laboratory-scale microcosm was built up to simulate the uptake, depuration, bioaccumulation, and stereoselective enrichment of DP in a lower concentration and equilibration condition. Common carp (Cyprinus carpio) were used for 32 days exposure and 32 days depuration. The concentration ratios of syn-DP to total DP (fₛyₙ values) in fish examined were lower than that in commercial products. Rate constants of uptake (kS) and elimination (kₑ) for the syn- and anti-DP were calculated using a first-order kinetic model. The uptake rate constants of syn- and anti-DP were 0.63 and 0.89 day⁻¹, respectively. The depuration rate constants of syn-DP (0.11 day⁻¹) were similar to anti-DP (0.096 day⁻¹), suggesting that anti-DP is absorbed faster than syn-DP by common carp. The estimated bioconcentration factors for both syn-DP (5700 L/kg) and anti-DP (9300 L/kg) were higher than the bioconcentration hazard criteria outlined in the Stockholm Convention, suggesting the bioconcentration potential to aquatic organisms for DP.

Anthropogenic disturbance of coastal ecosystems has increased the need for comprehensive methods and indicators to assess the health status of marine ecosystems. Biotic indices are important as they indicate different ecological states. In this study, Eco-Exergy-based indices (Exergy and Structural Exergy) and diversity indices (Shannon–Wiener index and Margalef index) were applied in the seas around the Zhoushan archipelago, and correlation analysis between biotic indices and environmental factors was used to test the robustness of these indices in capturing the environment changes, aimed to provide reference in selecting the indices for assessing marine eco-environment quality. Results showed that the benthic indices of Exergy, Shannon–Wiener, and Margalef increased with the distance from the mainland. The Eco-Exergy-based indices and Margalef index were significantly, negatively correlated with dissolved inorganic nitrogen and reactive phosphate, and significantly, positively correlated with the salinity of seawater. Overall, the marine ecosystem was more stable further away from the coast, where salinity was higher, and pollutants such as nutrients in seawater were lower. In addition, biodiversity and Eco-Exergy was also higher. Generally, Eco-Exergy-based indices were observed to be good indicators for detecting the environment changes in the study area.