This study investigated the distribution of moss species, physiological parameters (superoxide dismutase, peroxide, catalase, and total chlorophyll), and concentrations of potentially toxic elements (Mn, Cr, Zn, Cu, Pb, and Cd) in moss communities and topsoil at the Huayuan manganese mine, Xiangjiang manganese mine, and Nancha manganese mine (Southern China). Partial least squares path modeling (PLS-PM) was then performed to determine the relationship between the indicators. Cd, Mn, and Zn were the main topsoil pollutants, followed by Pb, Cr, and Cu. A total of 73 moss species, comprising 31 genera from 17 families, and 8 community functional groups were identified. The most dominant families were Pottiaceae (30.14%) and Bryaceae (21.92%). PLS-PM revealed that increasing topsoil Mn, Cr, Zn, Cu, Pb, and Cd significantly reduced species diversity and functional diversity. These potentially toxic elements in the topsoil impeded vegetation growth by deteriorating soil conditions and subsequently altering the microenvironment of the moss communities. The community-weighted means demonstrated that functional traits of turfs and warty leaves were the adaptation of the moss communities to an increasingly dry and exposed microenvironment. Moss species with curly and narrow leaves were used to reduce contact with particulate pollutants. PLS-PM also indicated that Mn, Cr, Pb, and Cd may have a detrimental effect on superoxide dismutase, peroxide, catalase, and total chlorophyll, although further validation studies are needed.

Soil Cd and Zn contamination has become a serious environmental problem. This work explored the performance of wood vinegar (WV) in enhancing the phytoextraction of Cd/Zn by hyperaccumulator Sedum alfredii Hance. Rhizosphere chemical properties, enzyme activities and bacterial community were analyzed to determine the mechanisms of metal accumulation in this process. Results demonstrated that, after 120 days growth, different times dilution of WV increased the shoot biomass of S. alfredii by 85.2%–148%. In addition, WV application significantly increased soil available Cd and Zn by lowing soil pH, which facilitated plant uptake. The optimal Cd and Zn phytoextraction occurred from the 100 times diluted WV (D100), which increased the Cd and Zn extraction by 188% and 164%, compared to CK. The 100 and 50 times diluted WV significantly increased soil total and available carbon, nitrogen and phosphorus, and enhancing enzyme activities of urease, acid phosphatase, invertase and protease by 10.1–21.4%, 29.1–42.7%,12.2–38.3% and 26.8–85.7%, respectively, compared to CK. High-throughput sequencing revealed that the D 100 significantly increased the bacterial diversity compared to CK. Soil bacterial compositions at phylum, family and genera level were changed by WV addition. Compared to CK, WV application increased the relative abundances of genus with plant growth promotion and metal mobilization function such as, Bacillus, Gemmatimonas, Streptomyces, Sphingomonas and Polycyclovorans, which was positively correlated to biomass, Cd/Zn concentrations and extractions by S. alfredii. Structural equation modeling analysis showed that, soil chemical properties, enzyme activities and bacterial abundance directly or indirectly contributed to the biomass promotion, Cd, and Zn extraction by S. alfredii. To sum up, WV improved phytoextraction efficiency by enhancing plant growth, Cd and Zn extraction and increasing soil nutrients, enzyme activities, and modifying bacterial community.

Solitary bees present greater species diversity than social bees. However, they are less studied than managed bees, mainly regarding the harmful effects of pesticides present in agroecosystems commonly visited by them. This study aimed to evaluate the effect of residual doses of imidacloprid and pyraclostrobin, alone and in combination, on the fat body (a multifunctional organ) of the neotropical solitary bee Tetrapedia diversipes by means of morphological and histochemical evaluation of oenocytes and trophocytes. Males and females of newly-emerged adults were submitted to bioassays of acute topical exposure. Experimental groups were essayed: control (CTR), solvent control (ACT), imidacloprid (IMI, 0.0028 ng/μL), pyraclostrobin (PYR, 2.7 ng/μL) and imidacloprid + pyraclostrobin (I + P). The data demonstrated that the residual doses applied in T. diversipes adults are sublethal at 96 h. Both oenocytes and trophocytes cells responded to topical exposure to the pesticides, showing morphological changes. In the IMI group, the bee oenocytes showed the greatest proportion of vacuolization and altered nuclei. The pyraclostrobin exposure increased the intensity of PAS-positive labeling (glycogen) in trophocytes. This increase was also observed in the I + P group. Changes in energy reserve (glycogen) of trophocytes indicate a possible mobilization impairment of this neutral polysaccharide to the hemolymph, which can compromise the fitness of exposed individuals. Also, changes in oenocytes can compromise the detoxification function performed by the fat body. This is the first study to show sublethal effects in neotropical solitary bees and highlight the importance of studies with native bees.

Decabromodiphenyl ethane (DBDPE) is a novel flame retardant that is widely used in plastics, electronic products, building materials and textiles. Our previous studies have revealed the oocyte toxicity of DBDPE, but the effect of DBDPE on preimplantation embryo development has not been reported. Here, we investigated whether and how DBDPE exposure affects preimplantation embryo development. Adult female mice were orally exposed to DBDPE (0, 5, 50, 500 μg/kg bw/day) for 14 days. First, we found that after DBDPE exposure, mice showed obvious circadian rhythm disorder. Moreover, the development of preimplantation embryos was inhibited in DBDPE-exposed mice after pregnancy. Then, we further explored and revealed that DBDPE exposure reduced the endogenous melatonin (MLT) level during pregnancy, thereby inhibiting the development of preimplantation embryos. Furthermore, we discovered that exogenous MLT supplementation (15 mg/kg bw/day) rescued the inhibition of preimplantation embryo development induced by DBDPE, and a mechanistic study demonstrated that exogenous MLT inhibited the overexpression of ROS and DNA methylation at the 5-position of cytosine (5-mC) in DBDPE-exposed preimplantation embryos. Simultaneously, MLT ameliorated the DBDPE-induced mitochondrial dysfunction by increasing the mitochondrial membrane potential (MMP), ATP, and Trp1 expression. Additionally, MLT restored DBDPE-induced changes in zona pellucida (ZP) hardness and trophectoderm (TE) cortical tension. Finally, the protective effect of MLT on embryos ameliorated the adverse reproductive outcomes (dead fetus, fetus with abnormal liver, fetal weight loss) induced by DBDPE. Collectively, DBDPE induced preimplantation embryo damage leading to adverse reproductive outcomes, and MLT has emerged as a potential tool to rescue adverse reproductive outcomes induced by DBDPE.

Mycotoxin is toxic secondary metabolite formed by certain filamentous fungi. This toxic compound can enter the food chain through contamination of food (e.g., by colonization of toxigenic fungi on food). In light of the growing concerns on the health hazards posed by mycotoxins, it is desirable to develop reliable analytical tools for their detection in food products in both sensitive and efficient manner. For this purpose, the potential utility of molecularly imprinted polymers (MIPs) has been explored due to their meritful properties (e.g., large number of tailor-made binding sites, sensitive template molecules, high recognition specificity, and structure predictability). This review addresses the recent advances in the application of MIPs toward the sensing of various mycotoxins (e.g., aflatoxins and patulin) along with their fabrication strategies. Then, performance evaluation is made for various types of MIP- and non-MIP-based sensing platforms built for the listed target mycotoxins in terms of quality assurance such as limit of detection (LOD). Further, the present challenges in the MIP-based sensing application of mycotoxins are discussed along with the future outlook in this research field.

Boscalid is a novel, highly effective carboximide fungicide that has been substantially and irrationally applied in greenhouses. However, little is known about the residual characteristics of boscalid and its ecological effects in long-term polluted greenhouse soils. Therefore, actual boscalid pollution status in greenhouse soils was simulated by repeatedly introducing boscalid into the soil under laboratory conditions. The degradation characteristics of boscalid, and its effects on the diversity, composition, function, and co-occurrence patterns of the soil microbial community were systematically investigated. Boscalid degraded slowly, with its degradation half-lives ranging from 31.5 days to 180.1 days in the soil. Boscalid degradation was further delayed by repeated treatment and increasing its initial concentration. Boscalid significantly decreased soil microbial diversity, particularly at the recommended dosage. Amplicon sequencing analysis showed that boscalid altered the soil microbial community and further stimulated the phylum Proteobacteria and four potential boscalid-degrading bacterial genera, Sphingomonas, Starkeya, Citrobacter, and Castellaniella. Although the network analysis revealed that boscalid significantly reduced the microbial network complexity, it enhanced the vital roles of Proteobacteria by increasing its proportion and strengthening the relationships among the internal bacteria in the network. The soil microbial function in the boscalid treatment were simulated at the recommended dosage and two-fold recommended dosage but showed an inhibition-recovery-stimulation trend at the five-fold recommended dosage with an increase in treatment frequency. Moreover, the expression of nitrogen cycling functional genes, nifH, AOA amoA, AOB amoA, nirK, and nirS in all boscalid treatments displayed an inhibition-recovery-stimulation trend during the entire experimental period, and the effects were more pronounced at the five-fold recommended dosage. In conclusion, repeated boscalid treatments delayed degradation, reduced soil microbial diversity and network complexity, disturbed soil microbial community, and interfered with soil microbial function.

The ionic strength of infiltration water changes with the seasonal alternation of irrigation sources. In this study, reactivity changes of birnessite-coated sand with the fluctuations of ionic strength of infiltration water (i.e. from groundwater to rainwater) and the involved mechanism were investigated through column experiments. Birnessite-coated sand was less reactive in groundwater than in rainwater because of the higher cation content and higher pH of groundwater. The cations in the groundwater were adsorbed on birnessite-coated sand and then desorbed in presence of a dilute aqueous solution represented by rainwater. The reactivity of the passivated birnessite-coated sand was recovered instantaneously, and approximately one-third of the pristine reactivity was restored. During recovery, Na⁺ desorption and lincomycin (LIN) removal both exhibited a two-stage reaction pattern. The LIN removal correlated with Na⁺ desorption (r = 0.99) so that the reactive sites that were binding 5.602 μmol of Na⁺ became available for 1 μmol of LIN removal. These results suggest that the reactivity of manganese oxides toward organic contaminant is associated with the ionic strength of infiltration water and indicate that the partial reactivity can be naturally restored.

Photoaging is an important reaction for waste plastics in the aquatic environment and plays a key role in the lifetime of plastics. Nevertheless, when natural photosensitive substances such as nitrate participate in this process, the physiochemical changes in plastics and the corresponding reaction mechanisms are not well-understood. In this work, the photochemical behavior of polyethylene terephthalate (PET) bottles in deionized water and nitrate solution was systematically investigated under ultraviolet (UV) irradiation. The analyses of the surface physicochemical properties of the photoaged PET bottles indicated that, after 20 days of photo-irradiation, the presence of nitrate reduced the contact angle from 69.8 ± 0.9° to 60.0 ± 0.3°, and increased the O/C ratio from 0.23 to 0.32, respectively. The leaching rate of dissolved organic carbon (DOC), which was 0.0193 mg g⁻¹·day⁻¹ in nitrate solution, was twice that of 0.00941 mg g⁻¹·day⁻¹ in deionized water. Furthermore, fluorescence spectroscopy revealed that the increasing DOC had aromatic rings with hydroxyl on the side-chain formed after UV irradiation. The positive effect of nitrate on the degradation of PET bottles was mainly through the generation of hydroxyl radicals that were produced through the photolysis of nitrate. In addition, two-dimensional correlation spectroscopy analysis showed that the chain scission of PET plastics could be initiated by nitrate-induced ·OH attacking the carbon-oxygen bonds instead of forming peroxides with oxygen. This work elucidates the mechanism of photodegradation of plastics that was induced by nitrate and highlights the important role of natural photosensitive substances in the photoaging process of plastics.

Forest fires can threaten amphibians because ash-associated contaminants transported by post-fire runoff impact both terrestrial and aquatic ecosystems. Still, the effects of these contaminants on the skin microbiome of amphibians have been overlooked. Thus, the main objective of this study was to assess the effects of ash from different severity wildfires (moderate and high) on the skin microbiome of the Iberian frog (Rana iberica). Bacterial isolates sampled from R. iberica skin microbiome were tested for their antimicrobial activity against the pathogen Aeromonas salmonicida. The isolates with antimicrobial activity were identified and further exposed to several concentrations (0, 6.25, 12.5, 25, 50, 75, and 100%) of Eucalypt (Eucalyptus globulus) aqueous extracts (AAEs) of ash from both a moderate and a high severity wildfire. The results showed that 53% of the bacterial isolates presented antimicrobial activity, with Pseudomonas being the most common genus. Exposure to AAEs had diverse effects on bacterial growth since a decrease, an increase or no effects on growth were observed. For both ash types, increasing AAEs concentrations led to an increase in the number of bacteria whose growth was negatively affected. Ash from the high severity fire showed more adverse effects on bacterial growth than those from moderate severity, likely due to the higher metal concentrations of the former. This study revealed that bacteria living in Iberian frogs' skin could be impaired by ash-related contaminants, potentially weakening the individual's immune system. Given the foreseen increase in wildfires' frequency and severity under climate change, this work raises awareness of the risks faced by amphibian communities in fire-prone regions, emphasising the importance of a rapid implementation of post-fire emergency measures for the preservation and conservation of this group of animals.