The immune organs, like thymus, are one of the targets of hydrogen sulfide (H₂S). Previously we reported that H₂S induced the differential expression of mRNAs that implicating apoptosis in thymus, however, the roles of noncoding RNAs (ncRNAs) in H₂S-induced thymus injury are still unknown. Pollution gases could alter the expression of ncRNAs, which have been shown to play important roles in many physiological and pathophysiological processes, including immune activity. This study revealed that H₂S exposure induced 9 differentially expressed circRNAs and 15 differentially expressed miRNAs in chicken thymus. Furthermore, the circRNA - miRNA - mRNA network was constructed. We discovered that circR-PTPN23 - miR-15a - E2F3 was involved in the cell cycle and apoptosis. Further, an in vitro H₂S exposure model was established using HD11 cell line and demonstrated that H₂S suppressed cell proliferation and induced apoptosis. Moreover, ciR-PTPN23 and E2F3 were downregulated, but miR-15a was upregulated in both the thymus and HD11 cell line after H₂S exposure. Bioinformatics analysis revealed that ciR-PTPN23 directly bound to miR-15a and that E2F3 was the target gene of miR-15a. Knocking down ciR-PTPN23 suppressed HD11 proliferation and caused G1 arrest and apoptosis, however, this phenomenon could be partially reversed by ciR-PTPN23 overexpression or miR-15a silencing. In summary, the ciR-PTPN23 - miR-15a - E2F3 axis was involved in H₂S-induced cell proliferation suppression and apoptosis.

1,2-dibromo-4-(1,2-dibromoethyl)-cyclohexane (DBE-DBCH) is a brominated flame retardant used in commercial and industrial applications. The use of DBE-DBCH containing products has resulted in an increased release into the environment. However, limited information is available on the long-term effects of DBE-DBCH and its effects in aquatic invertebrates. Thus, the present study was aimed at determining how DBE-DBCH diastereomers (αβ and γδ) affects aquatic invertebrates using Daphnia magna as a model organism. Survival, reproduction, feeding, swimming behavior and toxicogenomic responses to environmental relevant concentrations of DBE-DBCH were analyzed. Chronic exposure to DBE-DBCH resulted in decreased lifespan, and reduced fecundity. Expression of genes involved in reproductive processes, vtg1 and jhe, were also inhibited. DBE-DBCH also induced hypoxia by inhibiting the transcription of genes involved in heme biosynthesis and oxygen transport. Furthermore, DBE-DBCH also inhibited feeding resulting in emptiness of the alimentary canal. Increased expression of the stress response biomarkers was observed following DBE-DBCH exposure. In addition, DBE-DBCH diastereomers also altered the swimming behavior of Daphnia magna. The present study demonstrates that DBE-DBCH cause multiple deleterious effects on Daphnia magna, including effects on reproduction and hormonal systems. These endocrine disrupting effects are in agreement with effects observed on vertebrates. Furthermore, as is the case in vertebrates, DBE-DBCH γδ exerted stronger effects than DBE-DBCH αβ on Daphnia magna. This indicate that DBE-DBCH γδ has properties making it more toxic to all so far studied animals than DBE-DBCH αβ.

A full-scale, experimental landfarm was tested for the capacity to biodegrade oil-polluted soil under high-Arctic tundra conditions in northeast Greenland at the military outpost 9117 Station Mestersvig. Soil contaminated with Arctic diesel was transferred to the landfarm in August 2012 followed by yearly addition of fertilizer and plowing and irrigation to optimize microbial diesel biodegradation. Biodegradation was determined from changes in total petroleum hydrocarbons (TPH), enumeration of specific subpopulations of oil-degrading microorganisms (MPN), and changes in selected classes of alkylated isomers and isomer ratios. Sixty-four percent of the diesel was removed in the landfarm within the first year, but a recalcitrant fraction (18%) remained after five years. n-alkanes and naphthalenes were biodegraded as demonstrated by changing isomer ratios. Dibenzothiophenes and phenanthrenes showed almost constant isomer ratios indicating that their removal was mostly abiotic. Oil-degrading microorganisms were present for the major components of diesel (n-alkanes, alkylbenzenes and alkylnaphthalenes). The degraders showed very large population increases in the landfarm with a peak population of 1.2 × 10⁹ cells g⁻¹ of total diesel degraders. Some diesel compounds such as cycloalkanes, hydroxy-PAHs and sulfur-heterocycles had very few or no specific degraders, these compounds may consequently be degraded only by slow co-metabolic processes or not at all.

Quantum dots (QDs) are nanoparticles of inorganic semiconductors and have great promise in various applications. Many studies have indicated that mitochondria are the main organelles for the distribution and toxic effects of QDs. However, the underlying mechanism of QDs interacting with mitochondria and affecting their function is unknown. Here, we report the mechanism of toxic effects of 3-mercaptopropionic acid (MPA)-capped CdTe QDs on mitochondria. Human liver carcinoma (HepG2) cells were exposed to 25, 50 and 100 μmol/L of MPA-capped CdTe QDs. The results indicated that MPA-capped CdTe QDs inhibited HepG2 cell proliferation and increased the extracellular release of LDH in a concentration-dependent manner. Furthermore, MPA-capped CdTe QDs caused reactive oxygen species (ROS) generation and cell damage through intrinsic apoptotic pathway. MPA-capped CdTe QDs can also lead to the destruction of mitochondrial cristae, elevation of intracellular Ca²⁺ levels, decreased mitochondrial transmembrane potential and ATP production. Finally, we showed that MPA-capped CdTe QDs inhibited mitochondrial fission, mitochondrial inner membrane fusion and mitophagy. Taken together, MPA-capped CdTe QDs induced significant mitochondrial dysfunction, which may be caused by imbalanced mitochondrial fission/fusion and mitophagy inhibition. These findings provide insights into the regulatory mechanisms involved in MPA-capped CdTe QDs-induced mitochondrial dysfunction.

The sedimentary history of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) over the past 140 years in a lake sediment core from Huixian karst wetland was reconstructed. The total PAHs and OCPs concentrations ranged from 40.0 to 210 ng g⁻¹ and 0.98 to 31.4 ng g⁻¹, respectively. The vertical distribution of PAHs and OCPs in different stages was great consistent with the history of regional socio-economic development and the usage of OCPs. As the indicators of socio-economic development, gross domestic product (GDP), population, energy consumption, highway mileage, and private vehicles correlated with the PAHs concentrations, indicating the impact of human activities on PAHs levels. The PAHs and OCPs concentrations were also affected by environmental changes in the wetland, as reconstructed by total organic carbon (TOC), sand, silt, clay, quartz, and calcite in sediments. Redundancy analysis (RDA) results showed TOC was the dominant factor to explain the concentrations of PAHs and OCPs with the explanation of 86.7% and 43.5%, respectively. In addition, TOC content had significantly positive correlation with PAHs (0.96, p < 0.01) and OCPs (0.78, p < 0.01). In particular, the significantly positive correlation (p < 0.05) between calcite and PAHs and OCPs inferred that karstification might play an important role in the migration of PAHs and OCPs in the karst area. Therefore, the lake in Huixian wetland tended to be a sink more than a source of PAHs and OCPs influenced by the increasing TOC content and karstification under climate warming.

One active ingredient can be a component of different types of formulations of pesticides, while the toxicity of its formulations may vary depending on various constituents used in the mixture. The present study focuses on evaluating the effects of the active ingredient clomazone and its formulations (Rampa® EC and GAT Cenit 36 CS, both containing 360 g a.i./l of clomazone) on non-target aquatic macrophytes. The two formulation types differ in their active ingredient release and presumed environmental impact. In order to cover different ecological traits, two species of aquatic macrophytes – the floating monocot Lemna minor and the rooted dicot Myriophyllum aquaticum, were used as test models. The results of this study revealed differences in the sensitivity of tested plants to clomazone. Based on the most sensitive parameters, M. aquaticum proved to be more sensitive than L. minor to the technical ingredient and both formulations. The species sensitivity distribution (SSD) approach that was tried out in an attempt to create a higher tier step of risk assessment of clomazone for primary producers indicates that tests on rooted macrophytes can add value in risk assessment of plant protection products. The capsule formulation of clomazone was less toxic than the emulsion for L. minor, but more toxic for M. aquaticum. The most toxic for L. minor was the emulsifiable concentrate formulation Rampa® EC, followed by technical clomazone (EC₅₀ 33.3 and 54.0 mg a.i./l, respectively), while the aqueous capsule suspension formulation GAT Cenit 36 CS did not cause adverse effects. On the other hand, the most toxic for M. aquaticum was the formulation GAT Cenit 36 CS, followed by technical clomazone and the formulation Rampa® EC, demonstrating a greater effect of the capsule formulation.

Few studies have investigated the effect of personal PM₂.₅ and PM₁ exposures on heart rate variability (HRV) for a community-based population, especially in Asia. This study evaluates the effects of personal PM₂.₅ and PM₁ exposure on HRV during two seasons for 35 healthy adults living in an urban community in Taiwan. The low-cost sensing (LCS) devices were used to monitor the PM levels and HRV, respectively, for two consecutive days. The mean PM₂.₅ and PM₁ concentrations were 13.7 ± 11.4 and 12.7 ± 10.5 μg/m³ (mean ± standard deviation), respectively. Incense burning was the source that contributed most to the PM₂.₅ and PM₁ concentrations, around 9.2 μg/m³, while environmental tobacco smoke exposure had the greatest impacts on HRV indices, being associated with the highest decrease of 20.2% for high-frequency power (HF). The results indicate that an increase in PM₂.₅ concentrations of one interquartile range (8.7 μg/m³) was associated with a change of −1.92% in HF and 1.60% in ratio of LF to HF power (LF/HF). Impacts on HRV for PM₁ were similar to those for PM₂.₅. An increase in PM₁ concentrations of one interquartile range (8.7 μg/m³) was associated with a change of −0.645% in SDNN, −1.82% in HF and 1.54% in LF/HF. Stronger immediate and lag effects of PM₂.₅ exposure on HRV were observed in overweight/obese subjects (body mass index (BMI) ≥24 kg/m²) compared to the normal-weight group (BMI <24 kg/m²). These results indicate that even low-level PM concentrations can still cause changes in HRV, especially for the overweight/obese population.

Southeast Asia is particularly susceptible to the negative impacts of increasing coastal pollution as coastal populations and cities grow at unprecedented rates. Although water chemistry can be monitored, there are greater advantages in using bioindicators as reflectors of the combined effect of multiple pollution types on coastal ecosystem health and for early detection of the negative impacts of pollutants on biotic systems. This study explores the utility and application of ostracods as pollution bioindicators and examines the response of ostracod assemblages to variable pollution in Lap An Lagoon, central Vietnam. From 14 sites within the lagoon, 79 species of 46 genera were identified and sediment grain size, total organic carbon, organic matter and heavy metal concentration were measured. Cluster analysis, detrended correspondence analysis and canonical correspondence analysis identified four distinct ostracod biofacies that were highly correlated to the physical environmental variables (salinity, depth, sediment type, heavy metal concentrations, total organic carbon and organic matter) and are shown to be the main factors controlling ostracod biofacies. Low ostracod diversities were found in silty sediments with heavy metal concentrations likely toxic. Sinocytheridea impressa was indicative of a marginally polluted environment within the lagoon. This study provides evidence for the potential for Southeast Asian ostracods to be used in water quality assessments and the data collected can be used as a baseline for future pollution monitoring.

This experiment was conducted to evaluate the ecotoxicity of typical explosives and their mechanisms in the soil microenvironment. Here, TNT (trinitrotoluene), RDX (cyclotrimethylene trinitramine), and HMX (cyclotetramethylene tetranitramine) were used to simulate the soil pollution of single explosives and their combination. The changes in soil enzyme activity and microbial community structure and function were analyzed in soil, and the effects of explosives exposure on the soil metabolic spectrum were revealed by non-targeted metabonomics. TNT, RDX, and HMX exposure significantly inhibited soil microbial respiration and urease and dehydrogenase activities. Explosives treatment reduced the diversity and richness of the soil microbial community structure, and the microorganisms able to degrade explosives began to occupy the soil niche, with the Sphingomonadaceae, Actinobacteria, and Gammaproteobacteria showing significantly increased relative abundances. Non-targeted metabonomics analysis showed that the main soil differential metabolites under explosives stress were lipids and lipid-like molecules, organic acids and derivatives, with the phosphotransferase system (PTS) pathway the most enriched pathway. The metabolic pathways for carbohydrates, lipids, and amino acids in soil were specifically inhibited. Therefore, residues of TNT, RDX, and HMX in the soil could inhibit soil metabolic processes and change the structure of the soil microbial community.

Microplastic contamination in ecosystems has emerged as an environmental issue of global significance. This research quantified microplastics in oysters from 22 sites along Taiwan coastlines. In total, 6630 microplastic items were found in 660 oysters of two genera (Crassostrea and Saccostrea). The average content of microplastics was 3.24 ± 1.02 items/g (wet weight), ranging from 0.63 ± 0.52 items/g to 37.94 ± 19.22 items/g. Over half of the microplastics were smaller than 100 μm, and the most common shape was fragments (67%), followed by fibers (29%). The dominant color was transparent (49.76%), followed by black (25.66%). Polymer types were identified using a μRaman microscope, and the major component was polyethylene terephthalate (PET) (69.54%). Microplastic contamination was higher overall in wild than in farmed oysters. In addition, the microplastic content of oysters from northeastern waters was significantly greater than that of other oysters; this result is similar to the findings of previous research on floating marine litter and beach cleaning data. The results indicated that the average content of microplastic in oysters along the Taiwan coastline was similar to that in oysters in adjacent regions. This study suggests that innovative technologies should be implemented for monitoring and removing pollution, tracking marine pollution origins, and improving accountability and that plastic limitation strategies should be strengthened.