Traditional Chinese medicine residue (TCMR) is the solid substances remaining after the extraction of pharmaceutical ingredients from medicinal plant materials, which include abundant soil nutrients. However, TCMR is nearly lost as domestic garbage, which not only occupies a large amount of land but also leads to the waste of resource, as well as causing the eco-environment potential pollution. Therefore, we implemented this study to assess whether TCMR could be used as an organic fertilizer in agricultural practices for realizing waste resource utilization, improving soil fertility, and enhancing plant growth. The results showed that (1) application of TCMR could improve soil fertility, particularly in enhancing the soil contents of SOM, TN, NaOH-N, NaHCO₃-P, and HNO₃-K; (2) the higher application ratios of TCMR (0.8–1.0%) that increased the soil EC values would cause the risk of soil secondary salinization; (3) the lower application ratios of TCMR (0.2–0.6%) has a better positive effect on improved the maize seedlings’ physiological parameters and photosynthetic performance than the higher application ratios; (4) although application of TCMR lead to the heavy metal (Cr, Pb, Cd, As, and Hg) content increased in soil, there was no ecology risk under below 0.8% application ratio, compared with the China soil risk control standards, geo-accumulation index (Igₑₒ), and pollution load index (PLI). Thus, TCMR could potentially be used as an organic fertilizer in agricultural practices. This approach is an effective strategy not only for achieving TCMR disposal but also for realizing waste resource utilization, as well as for improving soil fertility and plant growth.

Mercury exposure has been shown to affect the reproductive system in many organisms, although the molecular mechanisms are still elusive. In the present study, we exposed Drosophila melanogaster Canton-S adult females to concentrations of 0 mM, 0.1 mM, 0.3 mM, 3 mM, and 30 mM of mercury chloride (HgCl₂) for 24 h, 48 h, or 72 h to determine how mercury could affect fertility. Alkaline assays performed on dissected ovaries showed that mercury induced DNA damage that is not only dose-dependent but also time-dependent. All ovaries treated for 72 h have incorporated mercury and exhibit size reduction. Females treated with 30 mM HgCl₂, the highest dose, had atrophied ovaries and exhibited a drastic 7-fold reduction in egg laying. Confocal microscopy analysis revealed that exposure to HgCl₂ disrupts germinal and somatic cell organization in the germarium and leads to the aberrant expression of a germline-specific gene in somatic follicle cells in developing egg chambers. Together, these results highlight the potential long-term impact of mercury on germline and ovarian cells that might involve gene deregulation.

Pro-thrombotic and inflammatory changes play an important role in cardiovascular morbidity and mortality, resulting from short-term exposure to fine particulate air-pollution. Part of those effects has been attributed to the ultra-fine particles (UFPs) that pass through the lung and directly contact blood-exposed and circulating cells. Despite UFP-induced platelet activation, it is unclear whether the penetrated particles exert any direct effect on endothelial cells. While exposure levels are boosting as a result of world-wide increases in economic development and desertification, which create more air-polluted regions, as well as increase in demands for synthetic UFPs in medicine and various industries, further studies on the health effects of these particles are required. In this study, human pulmonary and cardiac microvascular endothelial cells (MECs) have been exposed to 0.1, 1, 10, and 100 μg/ml suspensions of either a natural (carbon black) or a synthetic (multi-walled carbon nano-tubes) type of UFPs, in vitro. As a result, no changes in the levels of coagulation factor VIII, Von Willebrand factor, Interleukin 8, and P-selectin measured in the cells’ supernatant were observed prior to and 6, 12, and 24 h after exposure. In parallel, the spatio-temporal effect of UFPs on cardiac MECs was evaluated by Transmission Electron Microscopy. Despite phagocytic uptake of pure UFPs observed on cellular sections of the treated cells, Weibel-Palade bodies remained intact in shape and similar in number when compared with the untreated cells. Our work shows that carbon itself is a non-toxic carrier for endothelial cells.

Marine-derived fungi are relevant genetic resources for bioremediation of saline environments/processes. Among the five fungi recovered from marine sponges able to degrade pyrene (Py) and benzo[a]pyrene (BaP), Tolypocladium sp. strain CBMAI 1346 and Xylaria sp. CBMAI 1464 presented the best removal rates of Py and BaP, respectively. Since the decrease in BaP was related to mycelial adsorption, a combined strategy was applied for the investigation of Py degradation by the fungus Tolypocladium sp. CBMAI 1346. The selected fungus was able to degrade about 95% of Py after 7 days of incubation (optimized conditions), generating metabolites different from the ones found before optimization. Metabolites and transcriptomic data revealed that the degradation occurred mainly by the cytochrome P450 pathway. Putative monooxygenases and dioxygenases found in the transcriptome may play an important role. After 21 days of degradation, no toxicity was found in the optimized culture conditions. The findings from the present study highlight the potential of marine-derived fungi to degrade environmental pollutants and convey innovative information related to the metabolism of pyrene.

In this work, CuWO₄ is prepared and its effect of improving photocatalytic degradation of atrazine by TiO₂ as well as the synergetic mechanism is studied. Results show that the addition of CuWO₄ (50 mg/L) into the reaction system can significantly enhance the efficiency of atrazine degradation, resulting in an increased degradation efficiency of 92.1% after 270 min, which is 1.94 times higher than that of the single TiO₂. As the sintering temperate of CuWO₄ was increased, the degradation efficiency of atrazine increased initially and then deceased after reaching a maximum at 500 °C. The origin of the synergistic effect of TiO₂-CuWO₄ is attributed to the introduction of solid CuWO₄. The photochemical test results indicate that the photogenerated electrons transfer from irradiated TiO₂ to CuWO₄, which is beneficial to the O₂ reduction and H₂O₂ formation in aqueous solution thus promoting the photocatalytic activity of TiO₂. These observations unveil the importance of improving photocatalytic activity of TiO₂ with Cu-bearing semiconductors.

Mining activity is an important source of heavy metals in soil. Understanding the contents and distribution of heavy metals in mineral-waste soil and surrounding environments is important for the rational management of mines and reducing the migration of heavy metals to surrounding environments. We used a non-ferrous metal mine in southern China as a research object. Three types of sampling site (A–C) were established on the mineral-waste soil in the mining area and on nearby farmland (D) and along a river channel (E) outside the mining area: A, newly processed mineral-waste soil; B, steep 6-month-old stack of waste soil; C, gentle slope of 12-month-old waste soil; D, farmland soil within 1 km of the mine; and E, river water and adjacent soil. Soil samples were collected from the 0–10-cm layer at each site type. The contents and spatial distribution of Pb, Zn, and Cd at the sampling sites were analyzed, and the environmental risks were evaluated. The mean Pb, Zn, and Cd contents in the mining area (types A–C) were 2028, 3794, and 14.8 mg kg⁻¹, respectively, which were 8-, 19-, and 49-fold higher than the second-level limits of the Environmental Quality Standard for Soils of China, and the mean contents of Pb, Zn, and Cd for sites D and E were 76.4, 131, and 0.18 mg kg⁻¹ and 147, 194, and 0.95 mg kg⁻¹, respectively, all of which were under the second-level limits. Sites C and E were also used to analyze the spatial distribution of the Pb, Zn, and Cd contents. Geostatistical analysis found that the Pb, Zn, and Cd contents had a clear and similar spatial pattern at site C and generally decreased from north to south. Soil Pb, Zn, and Cd contents at site E generally increased, and water Pb, Zn, and Cd concentrations decreased along the river channel. The soils at site types A–C in the mining area were heavily polluted, with a high potential threat to the surrounding environment, and the farmland and river-bank soils at D and E were free of pollution or were lightly polluted, with low potential ecological risks. This study provides a scientific basis and supporting data for heavy-metal treatment in mining areas.

Poor removal of many pharmaceuticals and personal care products in sewage treatment plants leads to their discharge into the receiving waters, where they may cause negative effects for aquatic environment and organisms. In this study, electrochemical removal process has been used as alternative method for removal of mefenamic acid (MEF). For our knowledge, removal of MEF using electrochemical process has not been reported yet. Effects of initial concentration of mefenamic acid, sodium chloride (NaCl), and applied voltage were evaluated for improvement of the efficiency of electrochemical treatment process and to understand how much electric energy was consumed in this process. Removal percentage (R%) was ranged between 44 and 97%, depending on the operating parameters except for 0.1 g NaCl which was 9.1%. Consumption energy was 0.224 Wh/mg after 50 min at 2 mg/L of mefenamic acid, 0.5 g NaCl, and 5 V. High consumption energy (0.433 Wh/mg) was observed using high applied voltage of 7 V. Investigation and elucidation of the transformation products were provided by Bruker software dataAnalysis using liquid chromatography-time of flight mass spectrometry. Seven chlorinated and two non-chlorinated transformation products were investigated after 20 min of electrochemical treatment. However, all transformation products (TPs) were eliminated after 140 min. For the assessment of the toxicity, it was impacted by the formation of transformation products especially between 20 and 60 min then the inhibition percentage of E. coli bacteria was decreased after 80 min to be the lowest value.

Phytoremediation combined with amendments and stabilization technologies are two crucial methods to deal with soil contaminated with heavy metals. Copper (Cu) contamination in soil near Cu mines poses a serious threat to ecosystems and human health. This study investigated the effect of ethylenediaminetetraacetic acid (EDTA) and biochar (BC) on the accumulation and subcellular distribution of Cu in Amaranthus retroflexus L. to demonstrate the remediation mechanism of EDTA and BC at the cellular level. The role of calcium (Ca) in response to Cu stress in A. retroflexus was also elucidated. We designed a pot experiment with a randomized block of four Cu levels (0, 100, 200, 400 mg kg⁻¹) and three treatments (control, amendment with EDTA, and amendment with BC). The subcellular components were divided into three parts (cell walls, organelles, and soluble fraction) by differential centrifugation. The results showed that EDTA amendment significantly increased (p < 0.05) the concentrations of Cu in root cell walls and all subcellular components of stems and leaves (cell walls, organelles, and the soluble fraction). EDTA amendment significantly increased (p < 0.05) the proportion of exchangeable fraction and carbonate fraction in the soil. While BC amendment significantly decreased (p < 0.05) the concentrations of Cu in root cell walls and the root soluble fraction, it had no significant effects on Cu concentrations in the subcellular components of stems and leaves. The results revealed that EDTA mainly promoted the transfer of Cu to aboveground parts and accumulation in subcellular components of stems and leaves, while BC mainly limited Cu accumulation in root cell walls and the root soluble fraction. Ca concentrations in cell walls of roots, stems, and leaves increased as the Cu stress increased in all treatment groups, indicating that Ca plays an important role in relieving Cu toxicity in Amaranthus retroflexus L.

Poly-aluminium chloride (PAC) is often used to enhance phosphorus removal and control membrane fouling in membrane bioreactors (MBRs). However, the influence of aluminium accumulation on the biological nitrification and phosphorus removal of MBRs has not been well assessed. In the present study, the effects of accumulated aluminium on sludge activity and morphology were investigated in a lab-scale anoxic–oxic membrane bioreactor. The reasonably high removal efficiencies of NH₄⁺-N, TN, and COD, i.e. 94.9%, 84.8%, and 92.8%, respectively, were achieved in the reactor when the percentage of atomic aluminium on sludge surface increased to 14.2%. However, the decreases in the ammonia oxidation rate, nitrite oxidation rate, and specific oxygen uptake rate of sludge by 82.1%, 79.8%, and 46.4%, respectively, were observed. Meanwhile, the activity of phosphate-accumulating organisms was completely inhibited. Furthermore, the protein content in the extracellular polymeric substances of sludge decreased substantially, and the sludge became more dispersed due to the alum accumulation, compared with that of the initial phase. Therefore, long-term dosing of PAC in the MBR should be managed to avoid excessive aluminium accumulation in the sludge.