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The current state of environmental pollution with sulfur dioxide (SO2) in Poland based on sulfur concentration in Scots pine needles
2020
Likus-Cieślik, Justyna | Socha, Jarosław | Gruba, Piotr | Pietrzykowski, Marcin
The current air pollution by SO₂ due to anthropogenic pressure in Poland was assessed based on sulfur concentrations in pine needles (Pinus sylvestris L.). On 308 monitoring sample plots located in pine stands distributed across Poland, measurements were conducted in mineral soil layers (0–10 cm, 10–40 cm, 40–100 cm) and in the soil organic layer (+5–0 cm). Samples of Scots pine foliage (current-year needles) were then collected, and the sulfur concentration in these needles was determined. Based on these data, a map of the spatial variability of sulfur concentrations in pine needles was drawn. The mean sulfur concentration in the pine needles was 854.8 mg kg⁻¹ in dry mass. Higher SO₂ emissions were noted in regions influenced by industry, such as the Upper Silesia and regions under strong urban pressure. Sulfur concentrations in Scots pine needles were related to the stands' degrees of defoliation. A comparison of the current sulfur concentrations in pine needles from biomonitoring in 2015–2016 with those from previous biomonitoring (in 1983–1985, by Dmuchowski and Bytnerowicz (1995) showed that air quality has improved and SO₂ emissions have decreased.
اظهر المزيد [+] اقل [-]Toxicity of different forms of antimony to rice plants: Effects on reactive oxidative species production, antioxidative systems, and uptake of essential elements
2020
Zhu, Yanming | Wu, Qianhua | Lv, HaiQin | Chen, Wenxiang | Wang, Lizhen | Shi, ShengJie | Yang, JiGang | Zhao, PingPing | Li, Yuanping | Christopher, Rensing | Liu, Hong | Feng, RenWei
Antimonite [Sb(III)] and antimonate [Sb(V)] are known to have different toxicity to plants, but the corresponding mechanisms are not fully understood. This study was conducted to investigate reactive oxygen species (ROS), antioxidant systems, and levels of certain essential elements in response to exposure to Sb(III) and Sb(V). Results showed that exposure to Sb(V) caused oxidative stress in a rice plant (Yangdao No.6). Sb(III) was shown to be more toxic than Sb(V) as judged from a lower shoot biomass, a higher loss of essential elements, and higher production of superoxide anion free radicals (O₂⁻). The toxicity of Sb(III) might partially be due to the disturbance of the O₂ˉ dismutation reaction, which resulted in root cell membrane damage under exposure to 20 mg L⁻¹ Sb(III). Sb(V) stimulated the shoot fresh weight and the shoot uptake of many essential elements. Moreover, Sb(V) and Sb(III) both stimulated the accumulation of calcium in the shoots and roots, and calcium was found to significantly correlate with the concentrations of many essential elements and with some parameters correlated to antioxidant systems, suggesting a Ca-induced regulatory mechanism. The activity of glutathione peroxidase was significantly enhanced by Sb(V) and Sb(III), suggesting a role in scavenging hydrogen peroxide. Catalase was activated by exposure to 20 mg L⁻¹ Sb(III) in the roots and by exposure to 20 mg L⁻¹ Sb(V) both in the shoots and roots. However, peroxidase was activated by exposure to 5 mg L⁻¹ Sb(III) in the shoots and by exposure to 5 mg L⁻¹ Sb(V) in the roots. This study, for the first time, showed the differences between Sb(V) and Sb(III) toxicity when looking at the antioxidant response and essential element uptake.
اظهر المزيد [+] اقل [-]Glyphosate-based herbicides influence antioxidants, reproductive hormones and gut microbiome but not reproduction: A long-term experiment in an avian model
2020
Ruuskanen, Suvi | Rainio, Miia J. | Gómez-Gallego, Carlos | Selenius, Otto | Salminen, Seppo | Collado, Maria Carmen | Saikkonen, Kari | Saloniemi, Irma | Helander, Marjo
Controversial glyphosate-based herbicides (GBHs) are the most frequently used herbicides globally. GBH residues in the wild, in animal and human food may expose non-target organisms to health risks, yet the developmental and cumulative effects of GBHs on physiology and reproduction remain poorly understood. We present the first long-term study on the effects of subtoxic GBH exposure (160 mg/kg) on multiple key physiological biomarkers (cellular oxidative status and neurotransmitters), gut microbiome, reproductive hormones, and reproduction in an avian model. We experimentally exposed in Japanese quail females and males (Coturnix japonica) to GBHs and respective controls from the age of 10 days–52 weeks. GBH exposure decreased hepatic activity of an intracellular antioxidant enzyme (catalase), independent of sex, but did not influence other intracellular oxidative stress biomarkers or neurotransmitter enzyme (acetylcholinesterase). GBH exposure altered overall gut microbiome composition, especially at a younger age and in females, and suppressed potentially beneficial microbes at an early age. Many of the microbial groups increased in frequency from 12 to 28 weeks under GBH exposure. GBH exposure decreased male testosterone levels both at sexual maturity and at 52 weeks of exposure, but did not clearly influence reproduction in either sex (maturation, testis size or egg production). Future studies are needed to characterize the effects on reproductive physiology in more detail. Our results suggest that cumulative GBH exposure may influence health and reproduction-related traits, which is important in predicting their effects on wild populations and global poultry industry.
اظهر المزيد [+] اقل [-]Improved PM2.5 predictions of WRF-Chem via the integration of Himawari-8 satellite data and ground observations
2020
Hong, Jia | Mao, Feiyue | Min, Qilong | Pan, Zengxin | Wang, Wei | Zhang, Tianhao | Gong, Wei
The new-generation geostationary satellites feature higher radiometric, spectral, and spatial resolutions, thereby making richer data available for the improvement of PM₂.₅ predictions. Various aerosol optical depth (AOD) data assimilation methods have been developed, but the accurate representation of the AOD-PM₂.₅ relationship remains challenging. Empirical statistical methods are effective in retrieving ground-level PM₂.₅, but few have been evaluated in terms of whether and to what extent they can help improve PM₂.₅ predictions. Therefore, an empirical and statistics-based scheme was developed for optimizing the estimation of the initial conditions (ICs) of aerosol in WRF-Chem (Weather Research and Forecasting/Chemistry) and for improving the PM₂.₅ predictions by integrating Himawari-8 data and ground observations. The proposed method was evaluated via two one-year experiments that were conducted in parallel over eastern China. The contribution of the satellite data to the model performance was evaluated via a 2-week control experiment. The results demonstrate that the proposed method improved the PM₂.₅ predictions throughout the year and mitigated the underestimation during pollution episodes. Spatially, the performance was highly correlated with the amount of valid data.
اظهر المزيد [+] اقل [-]Size-fractionated carbonaceous aerosols down to PM0.1 in southern Thailand: Local and long-range transport effects
2020
Phairuang, Worradorn | Inerb, Muanfun | Furuuchi, Masami | Hata, Mitsuhiko | Tekasakul, Surajit | Phīraphong Thīkhasakun,
In this study, size-fractionated particulate matters (PM) down to ultrafine (PM₀.₁) particles were collected using a cascade air sampler with a PM₀.₁ stage, in Hat Yai city, Songkhla province, southern Thailand during the year 2018. The particle-bound carbonaceous aerosols (CA) as elemental carbon (EC) and organic carbon (OC) were quantified with the thermal/optical reflectance method following the IMPROVE_TOR protocol. The concentrations of different temperature carbon fractions (OC1-OC4, EC1-EC3 and PyO) in the size-fractionated PM were evaluated to discern OC and EC correlations as well as those between char-EC and soot-EC. The results showed that biomass burning, motor vehicle, and secondary organic aerosols (SOC) all contributed to the size-fractionated PM. The OC/EC ratios ranged from 2.90 to 4.30 over the year, with the ratios of PM₂.₅₋₁₀ being the highest, except during the open biomass burning period. The concentration of CA was found to increase during the pre-monsoon season and had its peak value in the PM₀.₅₋₁.₀ fraction. The long-range transport of PMs from Indonesia, southwest of Thailand toward southern Thailand became more obvious during the pre-monsoon season. Transported plumes from biomass burning in Indonesia may increase the concentration of OC and EC both in the fine (PM₀.₅₋₁.₀ and PM₁.₀₋₂.₅) and coarse (PM₂.₅₋₁₀ and PM>₁₀) fractions. The OC fraction in PM₀.₁ was also shown to be significantly affected by the transported plumes during the pre-monsoon season. Good OC and EC correlations (R² = 0.824–0.915) in the fine particle fractions indicated that they had common sources such as fossil fuel combustion. However, the lower and moderate correlations (R² = 0.093–0.678) among the coarser particles suggesting that they have a more complex pattern of emission sources during the dry and monsoon seasons. This indicates the importance of focusing emission control strategies on different PM particle sizes in southern Thailand.
اظهر المزيد [+] اقل [-]Dosage effects of lincomycin mycelial residues on lincomycin resistance genes and soil microbial communities
2020
Wang, Mengmeng | Liu, Huiling | Dai, Xiaohu
Lincomycin mycelial residues (LMRs) are one kind of byproduct of the pharmaceutical industry. Hydrothermal treatment has been used to dispose of them and land application is an attractive way to reuse the treated LMRs. However, the safe dose for soil amendment remains unclear. In this study, a lab-scale incubation experiment was conducted to investigate the influence of the amendment dosage on lincomycin resistance genes and soil bacterial communities via quantitative PCR and 16S rRNA sequencing. The results showed that introduced lincomycin degraded quickly in soil and became undetectable after 50 days. Degradation rate of the high amendment amount (100 mg kg−1) was almost 4 times faster than that of low amendment amount (10 mg kg−1). Moreover, the introduced LMRs induced the increase of lincomycin resistance genes after incubation for 8 days, and two genes (lmrA and lnuB) showed a dosage-related increase. For example, the abundance of gene lmrA was 17.78, 74.13 and 128.82 copies g−1 soil for lincomycin concentration of 10, 50 and 100 mg kg−1, respectively. However, the abundance of lincomycin resistance genes recovered to the control level as the incubation period extended to 50 days, indicating a low persistence in soil. In addition, LMRs application markedly shifted the bacterial composition and significant difference was found between control soil, 10 mg kg−1 and 50 mg kg−1 lincomycin amended soil. Actually, several genera bacteria were significantly related to the elevation of lincomycin resistance genes. These results provided a comprehensive understanding of the effects of lincomycin dosage on the fate of resistance genes and microbial communities in LMRs applied soil.
اظهر المزيد [+] اقل [-]Exploring plastic-induced satiety in foraging green turtles
2020
Santos, Robson G. | Andrades, Ryan | Demetrio, Guilherme Ramos | Kuwai, Gabriela Miki | Sobral, Mañana Félix | Vieira, Júlia de Souza | Machovsky-Capuska, Gabriel E.
In the last decade many studies have described the ingestion of plastic in marine animals. While most studies were dedicated to understanding the pre-ingestion processes involving decision-making foraging choices based on visual and olfactory cues of animals, our knowledge in the post-ingestion consequences remains limited. Here we proposed a theoretical complementary view of post-ingestion consequences, attempting to connect plastic ingestion with plastic-induced satiety. We analyzed data of plastic ingestion and dietary information of 223 immature green turtles (Chelonia mydas) from tropical Brazilian reefs in order to understand the impacts of plastic ingestion on foraging behavior. Generalized linear mixing models and permutational analysis of variance suggested that plastic accumulations in esophagus, stomach and intestine differed in their impact on green turtle’s food intake. At the initial stages of plastic ingestion, where the plastic still in the stomach, an increase in food intake was observed. The accumulation of plastic in the gastrointestinal tract can reduce food intake likely leading to plastic-induced satiety. Our results also suggest that higher amounts of plastics in the gastrointestinal tract may led to underweight and emaciated turtles. We hope that adopting and refining our proposed framework will help to clarify the post-ingestion consequences of plastic ingestion in wildlife.
اظهر المزيد [+] اقل [-]Effects of short-term exposure to environmentally-relevant concentrations of benzo(a)pyrene-sorbed polystyrene to White seabass (Atractoscion nobilis)☆
2020
Coffin, Scott | Magnuson, Jason T. | Vliet, Sara M.F. | Volz, David C. | Schlenk, Daniel
Plastic marine debris hyper-concentrates hydrophobic contaminants such as polycyclic aromatic hydrocarbons (PAHs) and can transfer these sorbed contaminants to biota following ingestion. PAHs are known to induce cardiotoxicity and visual toxicity at sublethal doses. Juvenile White seabass (Atractoscion nobilis) fish were fed environmentally relevant concentrations of either virgin polystyrene or benzo(a)pyrene (BaP)-sorbed polystyrene for 5 days and were monitored for changes in phototactic response, swimming behavior, and hepatic cytochrome p450 1A (CYP1A) enzyme activity. No significant differences in the monitored endpoints were recorded in fish that ingested either polystyrene or BaP-sorbed polystyrene relative to control fish following the short-term exposure. However, fish exposed to 252 μg/L BaP alone as a positive control had significantly elevated CYP1A enzyme activity (p = 0.046) and impaired phototactic response (p = 0.020), though no altered swimming behavior was observed (p = 0.843) relative to control fish. These results demonstrate that pelagic fish ingesting environmentally relevant concentrations of BaP-sorbed polystyrene for a short, 5-day duration do not demonstrate measurable changes in vision, swimming activity, nor CYP1A activity. High variability within enzyme activity and behavioral responses suggest that lack of significant effects may be due to low sample size.
اظهر المزيد [+] اقل [-]Influence of some physicochemical parameters on the passive sampling of copper (II) from aqueous medium using a polymer inclusion membrane device
2020
González-Albarrán, René | de Gyves, Josefina | Rodríguez de San Miguel, Eduardo
Recently polymer inclusion membranes (PIMs) have been proposed as materials for passive sampling, nonetheless a theoretical base to describe the mass transfer process through those materials, under such conditions of monitoring, has not been elucidated. Under the assumption that: (i) the transport of the metal ion occurs at steady state conditions, (ii) the concentration gradients are linear, and (iii) the kinetics of the chemical reactions in the extraction process on the membrane are elemental; an equation for the passive sampling of copper (II) using a PIM system containing Kelex-100 as carrier is derived. The prediction capacity of this sampler under different conditions of temperature, metal concentration, flow velocity, ionic strength and pH is analyzed as well. Among the dependencies of the PIM on the physicochemical conditions, effects of concentration, temperature and flow velocity tend to increment copper (II) flux across the membrane, being the parameter temperature the one with the most pronounced effect at T ≥ 30 °C. Ionic strength had no great effect on passive sampler response, however the sampler is dependent on the acidity of the medium. The comparable metal ion concentrations estimated from the PIM sampler to those obtained by direct measurements of the sampling medium suggest that PIMs can be robust materials when used as passive sampler devices.
اظهر المزيد [+] اقل [-]Hexavalent chromium induces mitochondrial dynamics disorder in rat liver by inhibiting AMPK/PGC-1α signaling pathway
2020
Yang, Qingyue | Han, Bing | Xue, Jiangdong | Lv, Yueying | Li, Siyu | Liu, Yan | Wu, Pengfei | Wang, Xiaoqiao | Zhang, Zhigang
Occupational exposure to hexavalent chromium (Cr(VI)) can cause cytotoxicity and carcinogenicity. In this study, we established a liver injury model in rats via intraperitoneal injection of potassium dichromate (0, 2, 4, and 6 mg/kg body weight) for 35 d to investigate the mechanism of Cr(VI)-induced liver injury. We found that Cr(VI) induced hepatic histopathological lesions, oxidative stress, and apoptosis and reduced the expression of mitochondrial-related regulatory factors such as adenosine 5′-monophosphate-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in a dose-dependent manner. Furthermore, Cr(VI) promoted mitochondrial division and inhibited fusion, leading to increased expression of caspase-3 and production of mitochondrial reactive oxygen species. Our study demonstrates that long-term exposure to Cr(VI) induces mitochondrial dynamics disorder by inhibiting AMPK/PGC-1α signaling pathway in rat liver.
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