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Survival outcomes of rehabilitated riverine turtles following a freshwater diluted bitumen oil spill
2022
Otten, Joshua G. | Williams, Lisa | Refsnider, Jeanine M.
Rehabilitation is often used to mitigate adverse effects of oil spills on wildlife. With an increase in production of alternatives to conventional crude oil such as diluted bitumen (dilbit), emergency spill responders and wildlife rehabilitators need information regarding the health and survival of free-ranging vertebrates exposed to dilbit under natural conditions. In 2010, one of the largest freshwater oil spills in the United States occurred in the Kalamazoo River in Michigan, when over 3.2 million liters of spilled dilbit impacted 56 km of riverine habitat. During 2010 and 2011 cleanup efforts, thousands of northern map turtles (Graptemys geographica) were captured from oiled stretches of the river, cleaned, rehabilitated, and released. We conducted extensive mark-recapture surveys in 2010, 2011, and 2018–2021, and used this dataset to evaluate the monthly survival probability of turtles 1–14 months post-spill and 8–11 years post-spill based on whether turtles were temporarily rehabilitated and released, overwintered in captivity and then released, or were released without rehabilitation. We found that rehabilitated or overwintered turtles had a higher probability of survival 1–14 months post-spill than non-rehabilitated turtles; however, 8–11 years post-spill the among-group differences in monthly survival probability had become negligible. Additionally, following the oil spill in 2010, nearly 6% of northern map turtles were recovered dead, died during rehabilitation, or suffered injuries that precluded release back into the wild. Our results demonstrate that exposure to dilbit in free ranging turtles causes direct mortality, while effort spent on the capture and rehabilitation of oiled freshwater turtles is important as it increases monthly survival 1–14 months post-spill.
Показать больше [+] Меньше [-]Generation of novel n-p-n (CeO2-PPy-ZnO) heterojunction for photocatalytic degradation of micro-organic pollutants
2022
Rajendran, Saravanan | Hoang, Tuan K.A. | Trudeau, Michel L. | Jalil, A.A. | Naushad, Mu | Awual, Md Rabiul
Recently, hetero junction materials (p-n-p and n-p-n) have been developed for uplifting the visible light activity to destroy the harmful pollutants in wastewater. This manuscript presents a vivid description of novel n-p-n junction materials namely CeO₂-PPy-ZnO. This novel n-p-n junction was applied as the photocatalyst in drifting the mobility of charge carriers and hence obtaining the better photocatalytic activity when compared with p-n and pure system. Such catalyst's syntheses were successful via the copolymerization method. The structural, morphological and optical characterization techniques were applied to identify the physio-chemical properties of the prepared materials. Additionally, the superior performance of this n-p-n nanostructured material was demonstrated in the destruction of micro organic (chlorophenol) toxic wastes under visible light. The accomplished ability of the prepared catalysts (up to 92% degradation of chlorophenol after 180 min of irradiation) and their profound degradation mechanism was explained in detail.
Показать больше [+] Меньше [-]Microbial community dynamics and their relationships with organic and metal pollutants of sugarcane molasses-based distillery wastewater sludge
2022
Tripathi, Sonam | Purchase, Diane | Al-Rashed, Sarah | Ram Chandra,
Distillery sludge is a major source of aquatic pollution, but little is known about their microbial community and their association with the organic and metal pollutants. Sugarcane molasses-based distillery is an important industry in India, although the waste is usually treated prior to disposal, the treatment is often inadequate. The adverse effects of the organic and metal pollutants in sugarcane molasses-based distillery sludge on the microbial biodiversity and abundance in the disposal site have not been elucidated. This study aims to address this gap of knowledge. Samples were collected from the discharge point, 1 and 2 km downstream (D1, D2, and D3, respectively) of a sugarcane distillery in Uttar Pradesh, India, and their physico-chemical properties characterised. Using QIIME, taxonomic assignment for the V3 and V4 hypervariable regions of 16 S rRNA was performed. The phyla Proteobacteria (28–39%), Firmicutes (20–28%), Bacteriodetes (9–10%), Actinobacteria (5–10%), Tenericutes (1–9%) and Patescibacteria (2%) were the predominant bacteria in all three sites. Euryechaeota, were detected in sites D1 and D2 (1–2%) but absent in D3. Spirochaetes (5%), Sinergistetes (2%) and Cloacimonetes (1%) were only detected in samples from site D1. Shannon, Simpson, Chao1, and Observed-species indices indicated that site D1 (10.18, 0.0013, 36706.55 and 45653.84, respectively) has higher bacterial diversity and richness than D2 (6.66, 0.0001, 25987.71 and 49655.89, respectively) and D3 (8.31, 0.002, 30345.53 and 30654.88, respectively), suggesting the organic and metal pollutants provided the stressors to favour the survival of microbial community that can biodegrade and detoxify them in the distillery sludge. This study confirmed that the treatment of the distillery waste was not sufficiently effective and provided new metagenomic information on its impact on the surrounding microbial community. It also offered new insights into potential bioremediation candidates.
Показать больше [+] Меньше [-]CircRNA-IGLL1/miR-15a/RNF43 axis mediates ammonia-induced autophagy in broilers jejunum via Wnt/β-catenin pathway
2022
Wang, Yue | Wang, Shengchen | Jing, Hongyuan | Zhang, Tianyi | Song, Nuan | Xu, Shiwen
With the continued increase of global ammonia emission, the damage to human or animal caused by ammonia pollution has attracted wide attention. The noncoding RNAs have been reported to regulate a variety of biological processes under different environmental stimulation via ceRNA (competing endogenous RNA) networks. Autophagy is a hallmark of tissue damage from air pollution. However, the specific role of circular RNAs (circRNAs) in the injury of intestinal tissue caused by autophagy remains unclear. Here, we established 42-days old ammonia-exposed broiler models and observed that autophagy flux in broiler jejunum was activated under ammonia exposure. Meanwhile, a total of eight significantly dysregulated expressed circRNAs were obtained and a circRNAs-miRNAs-genes interaction networks were constructed by bioinformatics analysis. Furthermore, an axis named circRNA-IGLL1/miR-15a/RNF43 was predicted to participate in the excessive autophagy by targeting RNF43. The target relationship was proved by dual-luciferase reporter assay in vitro. Mechanistically, downregulated circRNA-IGLL1 could suppress the expression of RNF43 in ammonia-exposed jejunum and the Wnt/β-catenin pathway was activated. Inhibition of miR-15a reversed autophagy caused by downregulated circRNA-IGLL1. CircRNA-IGLL1 could competitively bind miR-15a to regulate RNF43 expression, thus modulating the occurrence of autophagy. Taken together, our results showed that circRNA-IGLL1/miR-15a/RNF43 axis is involved in ammonia-induced intestinal autophagy in broilers.
Показать больше [+] Меньше [-]Opposite selection effects of nZVI and PAHs on bacterial community composition revealed by universal and sphingomonads-specific 16S rRNA primers
2022
Sheng, Dong | Chen, Minjie | Chen, Qiqi | Huang, Yili
Next-generation sequencing method employing the sphingomonads-specific and universal 16s rRNA primers were applied to analyze the response of soil bacterial community to continuous stress of nanoscale zero-valent iron (nZVI) and/or polycyclic aromatic hydrocarbons (PAHs) under suspended conditions. The group specific primer greatly improves taxonomic resolution, the overall OTU numbers increased from 12 by universal primer to 42 by sphingomonads-specific primer. It was found that nZVI and PAHs had opposite selection effects on bacterial community composition, furthermore, the abundance of Sphingopyxis was positively related to nZVI while negatively related to PAHs, whereas abundances of Sphingobium and Sphingosinicella were positively related to PAHs (p < 0.01). The improved taxonomic resolution helps identify the potential keystone taxa, which provides valuable information for future bioremediation technology such as synthetic microbiome.
Показать больше [+] Меньше [-]Effect of fulvic acid concentration levels on the cleavage of piperazinyl and defluorination of ciprofloxacin photodegradation in ice
2022
Li, Zhuojuan | Dong, Deming | Zhang, Liwen | Li, Yanchun | Guo, Zhiyong
Ice is an important physical and chemical sink for various pollutants in cold regions. The photodegradation of emerging fluoroquinolone (FQ) antibiotic contaminants with dissolved organic matter (DOM) in ice remains poorly understood. Here, the photodegradation of ciprofloxacin (CIP) and fulvic acid (FA) in different proportions as representative FQ and DOM in ice were investigated. Results suggested that the photodegradation rate constant of CIP in ice was 1.9 times higher than that in water. When CFA/CCIP ≤ 60, promotion was caused by FA sensitization. FA increased the formation rate of cleavage in the piperazine ring and defluorination products. When 60 < CFA/CCIP < 650, the effect of FA on CIP changed from promoting to inhibiting. When 650 ≤ CFA/CCIP ≤ 2600, inhibition was caused by both quenching effects of 143.9%–51.3% and light screening effects of 0%–48.7%. FA inhibited cleavage in the piperazine ring for CIP by the scavenging reaction intermediate of aniline radical cation in ice. When CFA/CCIP > 2600, the light screening effect was greater than the quenching effect. This work provides new insights into how DOM affects the FQ photodegradation with different concentration proportions, which is beneficial for understanding the environmental behaviors of fluorinated pharmaceuticals in cold regions.
Показать больше [+] Меньше [-]Phytoremediation of DEHP and heavy metals co-contaminated soil by rice assisted with a PGPR consortium: Insights into the regulation of ion homeostasis, improvement of photosynthesis and enrichment of beneficial bacteria in rhizosphere soil
2022
Liu, Anran | Wang, Wenjing | Chen, Xiancao | Zheng, Xiaoyan | Fu, Wenting | Wang, Gang | Ji, Jing | Guan, Chunfeng
The coexistence of di (2-ethylhexyl) phthalate (DEHP), Cd, and Zn poses a serious challenge to soil ecosystems. This study aimed to evaluate the phytoremediation potential of rice assisted with a plant growth promoting rhizobacteria (PGPR) consortium for the remediation of DEHP, Cd, and Zn co-contaminated soil. The consortium consisted of four bacterial strains, all of which exhibited Cd–Zn resistance and DEHP degradability. The results showed that the rice assisted by the bacterial consortium dissipated 86.1% DEHP while removing 76.0% Cd²⁺ and 92.2% Zn²⁺ from soil within 30 d. The presence of the PGPR consortium promoted plant growth and improved soil enzymatic activity, which may have helped enhance the removal of DEHP and heavy metals from the soil. Moreover, the application of the consortium modified the bacterial community and increased the relative abundance of bacteria related to DEHP degradation (Sphingomonas, Xanthobacteraceae), heavy metal immobilization (Massilia), and soil nutrient cycling (Nitrospira, Vicinamibacterales), which promoted plant growth and the removal of DEHP and heavy metals from soil. Notably, the DEHP and heavy metal contents in rice decreased substantially during the phytoremediation process. Therefore, the PGPR consortium could be beneficial for enhancing the removal of DEHP and heavy metals from the soil, without inducing the accumulation of these pollutants in rice. In general, this study confirmed that the combined use of rice and the PGPR consortium could remedy DEHP and heavy metal co-contaminated soil economically and ecologically without simultaneously posing risks for rice consumption.
Показать больше [+] Меньше [-]Alkylation modified pistachio shell-based biochar to promote the adsorption of VOCs in high humidity environment
2022
Cheng, Tangying | Li, Jinjin | Ma, Xiuwei | Zhou, Lei | Wu, Hao | Yang, Linjun
The objective of this work was to evaluate the adsorption capacity of alkylated modified porous biochar prepared by esterification and etherification (PSAC-2) for low concentrate volatile organic compounds (VOCs, toluene and ethyl acetate) in high humidity environment by experiments and theoretical calculations. Results showed that PSAC-2 has a large specific surface area and weak surface polarity, at 80% relative humidity, its capacities for toluene and ethyl acetate adsorption could be maintained at 92% and 87% of the initial capacities (169.9 mg/g and 96.77 mg/g). The adsorption behaviors of toluene, ethyl acetate, and water vapor were studied by adsorption isotherms, and isosteric heat was obtained. The desorption activation energy was obtained by temperature programmed desorption experiment. The outcomes manifested that the PSAC-2 can achieve strong adsorption performance for weakly polar molecules. Through density functional theory (DFT) simulations, owing to the interaction of hydrogen bonds, oxygen-containing groups became a significant factor influencing the adsorption of VOCs in humid environments. These results could provide an important reference for VOCs control in a high humidity environment.
Показать больше [+] Меньше [-]Where and how? A systematic review of microplastic pollution on beaches in Latin America and the caribbean (LAC)
2022
Mesquita, Yan Weber | Mengatto, Mateus Farias | Nagai, Renata Hanae
The dispersion of microplastics (MPs) in coastal and marine environments and their potential harmful effects on organisms and ecosystems makes MPs pollution an emerging problem that has gained increasing attention from the scientific community. Despite the recent increase in the number of studies on MPs presence in different marine environments, investigations in Latin America and the Caribbean (LAC) are still relatively limited. This review presents the spatial distribution (where) and the methods applied (how) in assessing MPs contamination on LAC sandy beaches, identifying the challenges to be faced in advancing the understanding of this emerging contaminant. Most of the 39 papers reviewed were published between 2020 and 2021 (51%) and conducted on Brazilian beaches (43%). The LAC investigations apply spot sampling (69%) on shoreline stretches between 10 and 1000 km (59%). These works used inconsistent sampling methods, incomparable techniques for MPs extraction from sediments, and different measurement units to report their data. The MPs presence on LAC beaches is not negligible, as it varies significantly in its distribution and concentration (0–2457 MP/dw kg and 0–5458 MP/m²). Its highest accumulation is on ocean island beaches; however, there are still large stretches of coastline (Cuba, Venezuela, Argentina) with no data on MPs presence and a small number of studies exploring these contaminants' temporal variability. The lack of standardization in the studies’ methodologies, particularly their measurement units, hinders their quantitative comparison and our ability to establish baseline values regarding MPs abundance on LAC beaches. In this sense, future works should direct efforts towards the spatial and temporal expansion of their sampling, as well as protocol standardization to facilitate result comparability on MPs on LAC sandy beaches.
Показать больше [+] Меньше [-]Tire microplastics exposure in soil induces changes in expression profile of immune-related genes in terrestrial crustacean Porcellio scaber
2022
Dolar, Andraž | Drobne, Damjana | Narat, Mojca | Jemec Kokalj, Anita
Tire particles pose a potential threat to terrestrial organisms because they are deposited in large quantities in the soil by tire wear abrasion, and moreover their chemical complexity poses an additional risk. Microplastics can affect several physiological processes in organisms, including those related to immunity. Therefore, we investigated the expression profile of selected immune-related genes (MnSod, Manganese Superoxide dismutase; Cat, Catalase; CypG, Cyclophilin G; Nos, Nitric oxide synthase; Ppae2a, Prophenoloxidase-activating enzyme 2a; Dscam, Down syndrome cell adhesion molecule; Myd88, Myeloid-differentiation factor 88; Toll4, Toll-like receptor 4; Mas-like, Masquerade-like protein) in haemocytes and the digestive gland hepatopancreas of terrestrial crustacean Porcellio scaber after two different time exposures (4 and 14 days) to tire particles in soil. Our results reveal for the first time the response of P. scaber after microplastic exposure at the transcriptome level. We observed time- and tissue-dependent changes in the expression of the analysed genes, with more pronounced alterations in haemocytes after 14 days of exposure. Some minor changes were also observed in hepatopancreas after 4 days. Changes in the expression profile of the analysed genes are a direct indication of a modulated immune status of the test organism, which, however, does not represent an adverse effect on the test organism under the given conditions. Nevertheless, the question remains whether the observed change in immune status affects the immunocompetence of the test organism.
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