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Degradation of glyphosate in a Colombian soil is influenced by temperature, total organic carbon content and pH 全文
2020
Muskus, Angelica M. | Krauss, Martin | Miltner, Anja | Hamer, Ute | Nowak, Karolina M.
Glyphosate is one of the most used herbicides in the world. The fate of glyphosate in tropical soils may be different from that in soils from temperate regions. In particular, the amounts and types of non-extractable residues (NER) may differ considerably, resulting in different relative contributions of xenoNER (sorbed and sequestered parent compound) and bioNER (biomass residues of degraders). In addition, environmental conditions and agricultural practices leading to total organic carbon (TOC) or pH variation can alter the degradation of glyphosate. The aim of this study is thus to investigate how the glyphosate degradation and turnover are influenced by varying temperature, pH and TOC of sandy loam soil from Colombia. The pH or TOC of a Colombian soil was modified to yield five treatments: control (pH 7.0, TOC 3%), 4% TOC, 5% TOC, pH 6.5, and pH 5.5. Each treatment received 50 mg kg⁻¹ of ¹³C₃¹⁵N-glyphosate and was incubated at 10 °C, 20 °C and 30 °C for 40 days. Rising temperature increased the mineralization of ¹³C₃¹⁵N-glyphosate from 13 to 20% (10 °C) to 32–39% (20 °C) and 41–51% (30 °C) and decreased the amounts of extractable ¹³C₃¹⁵N-glyphosate after 40 days of incubation from 13 to 26% (10 °C) to 4.6–12% (20 °C) and 1.2–3.2% (30 °C). Extractable ¹³C₃¹⁵N-glyphosate increased with higher TOC and higher pH. Total ¹³C-NER were similar in all treatments and at all temperatures (47%–60%), indicating that none of the factors studied affected the amount of total ¹³C-NER. However, ¹³C-bioNER dominated within the ¹³C-NER pool in the control and the 4% TOC treatment (76–88% of total ¹³C-NER at 20 °C and 30 °C), whereas in soil with 5% TOC and pH 6.5 or 5.5 ¹³C-bioNER were lower (47–61% at 20 °C and 30 °C). In contrast, the ¹⁵N-bioNER pool was small (between 14 and 39% of the ¹⁵N-NER). Thus, more than 60% of ¹⁵N-NER is potentially hazardous xenobiotic NER which need careful attention in the future.
显示更多 [+] 显示较少 [-]Glyphosate exposures and kidney injury biomarkers in infants and young children 全文
2020
Trasande, Leonardo | Aldana, Sandra India | Trachtman, Howard | Kannan, Kurunthachalam | Morrison, Deborah | Christakis, Dimitri A. | Whitlock, Kathryn | Messito, Mary Jo | Gross, Rachel S. | Karthikraj, Rajendiran | Sathyanarayana, Sheela
The goal of this study was to assess biomarkers of exposure to glyphosate and assess potential associations with renal function in children. Glyphosate is used ubiquitously in agriculture worldwide. While previous studies have indicated that glyphosate may have nephrotoxic effects, few have examined potential effects on kidney function in children. We leveraged three cohorts across different phases of child development and measured urinary levels of glyphosate. We evaluated associations of glyphosate with three biomarkers of kidney injury: albuminuria (ACR), neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury marker 1 (KIM-1). Multivariable regression analyses examined associations of glyphosate with kidney injury biomarkers controlling for covariates. We identified glyphosate in 11.1% of the total participants. The herbicide was detected more frequently in the neonate population (30%). Multivariable regression models failed to identify significant associations of log-transformed glyphosate with any of the kidney injury biomarkers, controlling for covariates age, sex, and maternal education. While we confirm detectability of glyphosate in children’s urine at various ages and stages of life, there is no evidence in this study for renal injury in children exposed to low levels of glyphosate. Further studies of larger sample size are indicated to better understand putative deleterious effects of the herbicide after different levels of exposure.
显示更多 [+] 显示较少 [-]3-Acetyldeoxynivalenol induces lysosomal membrane permeabilization-mediated apoptosis and inhibits autophagic flux in macrophages 全文
2020
Liu, Ning | Yang, Ying | Chen, Jingqing | Jia, Hai | Zhang, Yunchang | Jiang, Da | Wu, Guoyao | Wu, Zhenlong
3-Acetyldeoxynivalenol (3-Ac-DON), the acetylated derivative of deoxynivalenol (DON), has been reported to be coexisted with DON in various cereal grains. Ingestion of grain-based food products contaminated by 3-Ac-DON might exert deleterious effects on the health of both humans and animals. However, the biological toxicity of 3-Ac-DON on macrophages and the underlying mechanisms remain largely unknown. In the present study, we showed that RAW 264.7 macrophages treated with 0.75 or 1.50 μg/mL of 3-Ac-DON resulted in DNA damage and the related cell cycle arrest at G1 phase and cell death, activation of the ribotoxic stress and the endoplasmic reticulum (ER) stress responses. The 3-Ac-DON-induced cell death was accompanied by a protective autophagy, because gene silencing of Atg5 using the small interfering RNA enhanced cell death. Results of further experiments revealed a role for lysosomal membrane permeabilization in the 3-Ac-DON triggered inhibition of autophagic flux. Additional work also showed that increased lysosomal biogenesis and leakage of cathepsin B (CTSB) from lysosomes to cytosol was critical for the 3-Ac-DON-induced cell death. Importantly, 3-Ac-DON-induced DNA damage and cell death were rescued by CA-074-me, a CTSB inhibitor. Collectively, these results indicated a critical role of lysosomal membrane permeabilization in the 3-Ac-DON-induced apoptosis of RAW 264.7 macrophages.
显示更多 [+] 显示较少 [-]Elevated mercury concentrations in biota despite reduced sediment concentrations in a contaminated coastal area, Harboøre Tange, Denmark 全文
2020
Bjerregaard, Poul | Schmidt, Torben Grau | Mose, Maria Pedersen
Metals sequestered in coastal sediments are normally considered to be stable, but this investigation shows – somewhat surprisingly – that mercury concentrations in a previously contaminated area, Harboøre Tange, Denmark, have decreased since the 1980s. Mercury concentrations were determined in sediment and benthic biota and present values were compared to values in the 1980s and values from areas without known; history of mercury contamination. Concentrations in both the upper 20 cm of the sediments and; biota are considerably lower now compared to latest monitoring (1980s). Sediment.concentrations at most locations have decreased from the 100–300 ng Hg g⁻¹ dry weight (dw) level to levels below the Background Concentration (BC) of 50 ng Hg g⁻¹ dw defined by Oslo-Paris Convention for the Protection of the Marine Environment of the North-East Atlantic; some stations are at the 2–10 ng Hg g⁻¹ dw level characteristic of Danish coastal sediments with no known history of mercury contamination. Concentrations of mercury in the benthic biota along Harboøre Tange have also decreased since the 1980s but despite the lowered mercury concentrations in the sediments, concentrations in most samples of benthic invertebrate fauna still exceed those in uncontaminated coastal areas and also the Environmental Quality Standard (EQS) of 20 ng Hg g⁻¹ wet weight (≈100 ng Hg g⁻¹ dry weight) defined by the European Union’s Water Framework Directive. Concentration ranges in selected organisms are: (Harboøre Tange l980s/Harboøre Tange now/uncontaminated areas - given in ng Hg g⁻¹ dw): Periwinkles Littorina littorea 9000/150–450/55-77, blue mussels Mytilus edulis up to 9000/300–500/40–170, cockles Cerastoderma edule up to 8000/400–1200/200, brown shrimp Crangon crangon 700–2200/150-450/47, eelgrass Zostera marina up to 330/25–70/12. The present results - together with a literature review - show that a simple and straight forward relationship between the concentrations of mercury in sediment and benthic organisms does not necessarily exist.
显示更多 [+] 显示较少 [-]Characteristics of spatial and seasonal bacterial community structures in a river under anthropogenic disturbances 全文
2020
Ouyang, Liao | Chen, Huirong | Liu, Xinyue | Wong, Ming Hung | Xu, Fangfang | Yang, Xuewei | Xu, Wang | Zeng, Qinghuai | Wang, Weimin | Li, Shuangfei
In this study, the seasonal characteristics of microbial community compositions at different sites in a river under anthropogenic disturbances (Maozhou River) were analyzed using Illumina HiSeq sequencing. Taxonomic analysis revealed that Proteobacteria was the most abundant phylum in all sites, followed by Actinobacteria, Bacteroidetes, Chloroflexi, Acidobacteria and Firmicutes. The variations of the community diversities and compositions between the seasons were not significant. However, significant differences between sites as well as water and sediment samples were observed. These results indicated that sites under different levels of anthropogenic disturbances have selected distinct bacterial communities. pH, dissolved oxygen (DO), concentrations of total nitrogen (TN) and heavy metals were the main factors that influence the diversity and the composition of bacterial community. Specifically, the relative abundance of Proteobacteria was negatively correlated with pH and DO and positively correlated with TN, while Actinobacteria and Verrucomicrobia showed the opposite pattern. Moreover, positive correlations between the relative abundances of Firmicutes and Bacteroidetes and the concentration of heavy metals were also found. Results of functional prediction analysis showed no significant differences of the carbon, nitrogen and phosphorus metabolism across the sites and seasons. Potential pathogens such as Vibrio, Arcobacter, Acinetobacter and Pseudomonas were found in these samples, which may pose potential risks for environment and human health. This study reveals the effect of anthropogenic activities on the riverine bacterial community compositions and provides new insights into the relationships between the environmental factors and the bacterial community distributions in a freshwater ecosystem under anthropogenic disturbances.
显示更多 [+] 显示较少 [-]Determinants of personal exposure to fine particulate matter in the retired adults – Results of a panel study in two megacities, China 全文
2020
Li, Na | Xu, Chunyu | Liu, Zhe | Li, Ning | Chartier, Ryan | Chang, Junrui | Wang, Qin | Wu, Yaxi | Li, Yunpu | Xu, Dongqun
This study aimed to investigate the relationship between outdoor, indoor, and personal PM₂.₅ exposure in the retired adults and explore the effects of potential determinants in two Chinese megacities. A longitudinal panel study was conducted in Nanjing (NJ) and Beijing (BJ), China, and thirty-three retired non-smoking adults aged 43–86 years were recruited in each city. Repeated measurements of outdoor-indoor-personal PM₂.₅ concentrations were measured for five consecutive 24-h periods during both heating and non-heating seasons using real-time and gravimetric methods. Time-activity and household characteristics were recorded. Mixed-effects models were applied to analyze the determinants of personal PM₂.₅ exposure. In total, 558 complete sets of collocated 24-h outdoor-indoor-personal PM₂.₅ concentrations were collected. The median 24-h personal PM₂.₅ exposure concentrations ranged from 43 to 79 μg/m³ across cities and seasons, which were significantly greater than their corresponding indoor levels (ranging from 36 to 68 μg/m³, p < 0.001), but significantly lower than outdoor levels (ranging from 43 to 95 μg/m³, p < 0.001). Indoor and outdoor PM₂.₅ concentrations were the strongest determinants of personal exposures in both cities and seasons, with RM² ranging from 0.814 to 0.915 for indoor and from 0.698 to 0.844 for outdoor PM₂.₅ concentrations, respectively. The personal-outdoor regression slopes varied widely among seasons, with a pronounced effect in BJ (NHS: 0.618 ± 0.042; HS: 0.834 ± 0.023). Ventilation status, indoor PM₂.₅ sources, personal characteristics, and meteorological factors, were also found to influence personal exposure levels. The city and season-specific models developed here are able to account for 89%–93% of the variance in personal PM₂.₅ exposure. A LOOCV analysis showed an R² (RMSE) of 0.80–0.90 (0.21–0.36), while a 10-fold CV analysis demonstrated a R² (RMSE) of 0.83–0.90 (0.20–0.35). By incorporating potentially significant determinants of personal exposure, this modeling approach can improve the accuracy of personal PM₂.₅ exposure assessment in epidemiologic studies.
显示更多 [+] 显示较少 [-]Selecting the best stabilization/solidification method for the treatment of oil-contaminated soils using simple and applied best-worst multi-criteria decision-making method 全文
2020
Kujlu, Rahele | Moslemzadeh, Mehrdad | Rahimi, Somayeh | Aghayani, Ehsan | Ghanbari, Farshid | Mahdavianpour, Mostafa
Oil-contaminated soils resulted from drilling activities can cause significant damages to the environment, especially for living organisms. Treatment and management of these soils are the necessity for environmental protection. The present study investigates the field study of seven oil-contaminated soils treated by different stabilization/solidification (S/S) methods, and the selection of the best treated site and treatment method. In this study, first, the ratios of consumed binders to the contaminated soils (w/w) and the treatment times for each unit of treated soils were evaluated. The ratios of consumed binders to the contaminated soils were between 6 and 10% and the treatment times for each unit of treated soils were between 4.1 and 18.5 min/m³. Physicochemical characteristics of treated soils were also determined. Although S/S methods didn’t change the water content of treated soils, they increased the porosity of soils. Unexpectedly, the cement-based S/S methods didn’t increase the pH of the treated soils. The highest and the lowest leaching of petroleum hydrocarbons was belonging to S/S using diatomaceous earth (DE) and the combination of Portland cement, sodium silicate and DE (CS-DE), respectively. The best acid neutralization capacity was obtained for soils treated using the combination of Portland cement and sodium silicate (CS). Based on the best-worst multi-criteria decision-making method (BWM-MCDM), the soils treated using CS-DE was select as the best. The BWM-MCDM can be used as an effective tool for the selection of the best alternative in all areas of environmental decontamination.
显示更多 [+] 显示较少 [-]Trends of production, consumption and environmental emissions of Decabromodiphenyl ether in mainland China 全文
2020
Chen, Yuan | Li, Jinhui | Tan, Quanyin
Decabromodiphenyl ether (DecaBDE) is a brominated flame retardant belonging to the group of polybrominated diphenyl ethers. DecaBDE has been widely used for various applications, such as plastics, textiles, and building and construction materials. Limited information on DecaBDE production and usage inventory has been elaborated, however. Therefore, this work aimed to produce a preliminary emissions inventory of DecaBDE in mainland China by estimating production and consumption amounts of DecaBDE, and characterizing its emission factors during production and usage, based on industrial investigation and theoretical prediction. It was indicated that the total production of DecaBDE reached 464.68 thousand metric tons (kt), of which 62.72 kt were exported, since the beginning of its production. Shandong and Jiangsu provinces dominate the production, with proportions of 77.95% and 18.45%, respectively. The production stage releases most of the DecaBDE to the atmosphere, with an emissions factor of 23 ± 1.9 kg/t, followed by 20 ± 0.9 kg/t DecaBDE to waste water and 16 ± 1.0 kg/t DecaBDE as solid residue. DecaBDE emissions in the consumption stage—namely the plastic production process—are 0.17 ± 0.06–0.23 ± 0.08 kg DecaBDE to the atmosphere and 1.72 ± 0.58–2.29 ± 0.77 kg DecaBDE to solid residue, for each metric ton of plastic produced. The total annual DecaBDE emissions to waste water are 93.98–1140.9 mg—negligible. The results showed that the sources of DecaBDE environmental pollution are its manufacturing and flame-retardant plastic modification plants, which are easily overlooked by both the government and the public. Yet DecaBDE emissions elimination and the environmentally sound management of the DecaBDE waste generated from these two processes are crucial for environmental protection.
显示更多 [+] 显示较少 [-]Transfer of dechlorane plus between human breast milk and adipose tissue and comparison with legacy lipophilic compounds 全文
2020
Pan, Hai-Yan | Li, Ji-Fang-Tong | Li, Xing-Hong | Yang, You-Lin | Qin, Zhan-Fen | Li, Jin-Bo | Li, Yuan-Yuan
In this study, levels of dechlorane plus (DP) in breast milk and matched adipose tissue samples were measured from 54 women living in Wenling, China. Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured simultaneously for comparison. The levels of ∑DPs/∑PBDEs varied from less than one to several dozens of ng g⁻¹ lipid weight (lw) in matrices and the levels of ∑PCBs varied between several to hundreds of ng g⁻¹ lw. In the same matrix, ∑DPs and ∑PCBs/∑PBDEs showed a significant relationship (p < 0.05), indicating that they shared common sources. Accordingly, there was a strong association of lipid-adjusted concentrations of individual compounds (BDE-209 excluded) between matrices (p < 0.001), suggesting that breast milk could be a proxy for adipose tissue in human bioburden monitoring of these compounds. The predicted lipid-adjusted milk/adipose ratios varied from 0.62 to 1.5 but showed significant differences (p<0.001) between compounds, suggesting a compound-specific transfer between milk lipids and adipose tissue lipids. Specifically, the milk/adipose ratios for syn-DP and anti-DP (−1.40 and 1.3, respectively) were significantly higher than those of CB congeners and hexa/hepta-BDE congeners (p < 0.05). In addition, unlike PCBs/PBDEs (excluding BDE-209), DP’s hydrophobicity might not be responsible for its preferable distribution in milk lipids. Instead, the interaction with nonlipid factors played a key role. The fraction of anti-DP between the two kinds of matrices was not significantly different, suggesting that the biochemical transfer processes may not be efficient enough to distinguish DP isomers. Nevertheless, the congener patterns of PCBs/PBDEs gave a clue about the compound-specific transfer between milk and adipose tissue. To our knowledge, this is the first to report the relationships of DP between adipose tissue and breast milk. These results could provide useful and in-depth information on biomonitoring of DP and facilitate the understanding of the accumulation and excretion potentials of DP and its distribution-related mechanism in humans.
显示更多 [+] 显示较少 [-]Environmental and human health issues related to long-term contamination by chlordecone in the French Caribbean 全文
2020
Benoit, Pierre | Cravedi, Jean Pierre, J. P. | Desenclos, J-C. | Mouvet, Christophe | Rychen, Guido | Samson, Michel | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | ToxAlim (ToxAlim) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Ecole d'Ingénieurs de Purpan (INP - PURPAN) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Santé publique France - French National Public Health Agency [Saint-Maurice, France] | Bureau de Recherches Géologiques et Minières (BRGM) | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Université de Lorraine (UL)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Institut de recherche en santé, environnement et travail (Irset) ; Université d'Angers (UA)-Université de Rennes (UR)-École des Hautes Études en Santé Publique [EHESP] (EHESP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes (Biosit : Biologie - Santé - Innovation Technologique) | ANR-16-CE21-0008,INSSICCA,Stratégies innovantes pour sécuriser les systèmes d'élevage dans les zones contaminées par la chlordécone. Une approche modèle développée dans les Antilles et applicable dans les zones contaminées à l'échelle mondiale(2016)
International audience
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