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Serum bisphenol A analogues in women diagnosed with the polycystic ovary syndrome – is there an association? Texte intégral
2021
Jurewicz, Joanna | Majewska, Joanna | Berg, Andrzej | Owczarek, Katarzyna | Zajdel, Radosław | Kaleta, Dorota | Wąsik, Andrzej | Rachoń, Dominik
Due to the endocrine disrupting effects of bisphenol A (BPA) several governmental authorities have banned its use and the manufacturers had to find alternative substances with similar chemical properties. This led to the increase in the use of so-called BPA analogues, which however also turn out to possess mild estrogenic and ani-androgenic properties and thus, may cause fertility problems and sex-hormone dependent endocrinopathies. The aim of this study was to evaluate the potential association between the exposure to BPA and its two analogues: BPS and BPF, with the diagnosis of the polycystic ovary syndrome (PCOS), which remains the most common female endocrinopathy. Serum concentrations of BPA, BPS and BPF were measured using high performance liquid chromatography method with tandem mass spectrometry (HPLC-MS/MS) among 199 women with PCOS and 158 control subjects. In women with PCOS serum BPS concentrations were significantly higher compared to the control subjects (geometric mean [95% CI]: 0.14 ng/mL [0.10; 1.17] vs. 0.08 ng/mL [0.06; 0.09], P = 0.023). Serum BPA and BPF concentrations did not differ between the studied groups. There was however a negative correlation between serum BPA and HOMA-IR (r = − 0.233, P = 0.001) and TST (r = − 0.203, P = 0.006) in women with PCOS. No correlations were found between the serum BPs and other metabolic parameters such as serum lipids, insulin, DHEA-S, androstenedione and FAI. When studying the association between serum BPA analogues and PCOS it turned out that women whose serum BPS concentrations were in the first tertile were more likely to be diagnosed with this endocrinopathy (OR [95% CI]: 1.21 [1.04; 3.46], P = 0.017). This association was also statistically significant when adjusted for age, education, BMI, smoking, income, and alcohol consumption (adjusted OR [95% CI]: 1.12 [1.03; 3.71], P = 0.029). These results point to the potential association between the exposure to BPS and the diagnosis of PCOS. The role of BPA is not clear and warrants further studies.
Afficher plus [+] Moins [-]Bisphenol AF induces apoptosis via estrogen receptor beta (ERβ) and ROS-ASK1-JNK MAPK pathway in human granulosa cell line KGN Texte intégral
2021
Huang, Mingquan | Li, Xingjie | Jia, Shengjun | Liu, Shuang | Fu, Li | Jiang, Xue | Yang, Meng
Bisphenol AF (BPAF) is an emerging environmental pollutant. Although BPAF is widely spread in the environment and human surroundings, its interference with ovarian function has not been fully elucidated. The aim of this study was to identify the mechanism underlying the effect of BPAF on the apoptosis of KGN cells, which maintain the physiological characteristics of ovarian granulosa cells. Our results indicated that BPAF induces KGN cell apoptosis in a concentration- and time-dependent manner. Meanwhile, BPAF exposure significantly promoted the expression of pro-apoptotic proteins, including Bax, Bid and Bak, while the expression of anti-apoptotic proteins, such as Bcl-2, Bcl-xL and Mcl-1, decreased significantly. We further detected a significant increase in intracellular ROS levels in response to high concentrations of BPAF exposure. After blocking the corresponding pathway, it was found that ROS mediates ASK1 and JNK activation. Furthermore, the role of Ca²⁺ overload and estrogen receptor β (ERβ) in BPAF-induced KGN cell apoptosis was also confirmed by using inhibitors. These results suggest that BPAF has potential reproductive toxicity for females, and ROS-ASK1-JNK axis may play a key role in BPAF-induced ovarian dysfunction. In addition, Ca²⁺ overload and ERβ pathway activation may also be an important mechanism of reproductive toxicity of BPAF.
Afficher plus [+] Moins [-]Elucidating the impact of three metallic nanoagrichemicals and their bulk and ionic counterparts on the chemical properties of bulk and rhizosphere soils in rice paddies Texte intégral
2021
Growing applications of nanoagrichemicals have resulted in their increasing accumulation in agricultural soils, which could modify soil properties and affect soil health. A greenhouse pot trial was conducted to determine the effects of three metallic nanoagrichemicals on several fundamental chemical properties of a rice paddy soil, including zinc oxide nanoparticles (ZnO NPs) and copper oxide nanoparticles (CuO NPs) at 100 mg/kg, and silicon oxide nanoparticles (SiO₂ NPs) at 500 mg/kg, as well as their bulk and ionic counterparts. The investigated soil amendments displayed significant and distinctive impact on the examined soil chemical properties relevant to agricultural production, including soil pH, redox potential, soil organic carbon (SOC), cation exchange capacity (CEC), and plant available As. For example, all amendments increased the bulk soil pH at day 47 to some extent, but the increase was substantially higher for SiO₃²⁻ (37.7%) than other amendments (5.8%–13.7%). Soil Eh was elevated markedly at day 47 after the addition of soil amendments in both the bulk soil (45.9%–74.4%) and rice rhizosphere soil (20.3%–68.9%). CuO NPs and Cu²⁺ generally exhibited greater impact on soil chemical properties than other agrichemicals. Significantly different responses to soil amendments were observed between bulk and rhizosphere soils, suggesting the essential role of plants in affecting soil properties and their responses to environmental disturbance. Overall, our results confirmed that the tested amendments could have remarkable impacts on the fundamental chemical properties of rice paddy soils.
Afficher plus [+] Moins [-]Interactive effects of microplastic pollution and heat stress on reef-building corals Texte intégral
2021
Plastic pollution is an emerging stressor that increases pressure on ecosystems such as coral reefs that are already challenged by climate change. However, the effects of plastic pollution in combination with global warming are largely unknown. Thus, the goal of this study was to determine the cumulative effects of microplastic pollution with that of global warming on reef-building coral species and to compare the severity of both stressors. For this, we conducted a series of three controlled laboratory experiments and exposed a broad range of coral species (Acropora muricata, Montipora digitata, Porites lutea, Pocillopora verrucosa, and Stylophora pistillata) to microplastic particles in a range of concentrations (2.5–2500 particles L⁻¹) and mixtures (from different industrial sectors) at ambient temperatures and in combination with heat stress. We show that microplastic can occasionally have both aggravating or mitigating effects on the corals’ thermal tolerance. In comparison to heat stress, however, microplastic constitutes a minor stressor. While heat stress led to decreased photosynthetic efficiency of algal symbionts, and increased bleaching, tissue necrosis, and mortality, treatment with microplastic particles had only minor effects on the physiology and health of the tested coral species at ambient temperatures. These findings underline that while efforts to reduce plastic pollution should continue, they should not replace more urgent efforts to halt global warming, which are immediately needed to preserve remaining coral reef ecosystems.
Afficher plus [+] Moins [-]An in-situ bio-remediation of nitrobenzene in stimulated aquifer using emulsified vegetable oil Texte intégral
2021
Widespread nitrobenzene (NB) contamination in groundwater requires an economical and effective remediation technology. In situ microbial reactive zone enhanced by injecting emulsified vegetable oil (EVO) is an effective method for remediating NB-contaminated groundwater, which can be reduced to aniline (AN) effectively in the reactive zone. However, the bio-mechanism of NB remediation in a real contaminated site is still unclear. Thus, a 3-D tank was established to conduct a pilot-scale experiment and the bacterial communities in the tank were analyzed by 16S rDNA high-throughput sequencing. The results suggested that the injection of EVO can stimulate some certain microorganisms to grow, and reduce NB though biological and biochemical processes. There were three degradation pathways of NB: (1) direct oxidation by Pseudomonas; (2) direct mineralization by Clostridium sensu stricto; and (3) coupled reduction of NB through microbial dissimilatory iron reduction by Geobacter and Arthrobacter. Among these pathways, the coupled reduction process is the main degradation pathway.
Afficher plus [+] Moins [-]Low density polyethylene degradation by filamentous fungi Texte intégral
2021
Polyethylene (PE) is the most abundant non-degradable plastic waste, posing a constant and serious threat to the whole ecosystem. In the present study, the fungal community of plastic wastes contaminating a landfill soil has been studied. After 6 months of enrichment, 95 fungi were isolated, mostly belonging to the Ascomycota phylum. They were screened under in vitro condition: most of fungi (97%) were capable of growing in the presence of PE powder (5–10 g L⁻¹) as sole carbon source. Fusarium strains better tolerated high concentration of PE. Up to 13 strains were chosen for further degradation trails, where the process was monitored by respirometry tests and by observing changes in PE chemical and physical structure by FTIR analysis and SEM images. Major results were observed for Fusarium oxysporum, Fusarium falciforme and Purpureocillum lilacinum, as they caused strong oxidation phenomena and changes in the PE film morphology. Results suggested that the initial oxidation mechanisms targeted first the methyl terminal groups. Changes in the infrared spectra were strongly strain-dependent, denoting the activation of different degradation pathways. Through the SEM analysis, the actual damages provoked by fungi were observed, including swellings, pits and furrows, bumps and partial exfoliations. Considering the rising concern about plastic disposal worldwide, the ability of these fungi to colonize PE and utilize it as carbon source is of great interest, as no pretreatments and pro-oxidant stimulants were needed.
Afficher plus [+] Moins [-]Quantitative and qualitative evaluation of plastic particles in surface waters of the Western Black Sea Texte intégral
2021
Pojar, Iulian | Kochleus, Christian | Dierkes, Georg | Ehlers, Sonja M. | Reifferscheid, Georg | Stock, Friederike
Microplastic abundances have been studied intensively in the last years in marine and freshwater environments worldwide. Though several articles have been published about the Mediterranean Sea, only few studies about the Black Sea exist. The Black Sea drains into the Mediterranean Sea and may therefore significantly contribute to the Mediterranean marine pollution. So far, only very few articles have been published about micro-, meso- and macroplastic abundances in the Western Black Sea. In order to fill this knowledge gap and to decipher the number of plastics on the water surface, 12 samples were collected from surface waters with a neustonic net (mesh size 200 μm) in the Black Sea close to the Danube Delta and the Romanian shore. Organic matter was digested and plastic particles were isolated by density separation. The results of visual inspection, pyrolysis GC-MS (for microplastics) and ATR-FTIR (for mesoplastics >5 mm) revealed an average concentration of 7 plastic particles/m³, dominated by fibers (∼76%), followed by foils (∼13%) and fragments (∼11%). Only very few spherules were detected. The polymers polypropylene (PP) and polyethylene (PE) dominated which is in line with other studies analyzing surface waters from rivers in Western Europe as well as in China. Statistical analyses show that the plastic concentration close to the mouth of the Danube River was significantly higher than at four nearshore regions along the Romanian and Bulgarian coastline. This could be explained by plastic inputs from the Danube River into the western part of the Black Sea.
Afficher plus [+] Moins [-]Traditional and novel organophosphate esters (OPEs) in PM2.5 of a megacity, southern China: Spatioseasonal variations, sources, and influencing factors Texte intégral
2021
Zeng, Yuan | Chen, She-Jun | Liang, Yao-Hui | Zhu, Chun-You | Liu, Zheng | Guan, Yu-Feng | Ma, Hui-Min | Mai, Bi-Xian
Organophosphate esters (OPEs) are ubiquitous contaminants in the environment, whereas their atmospheric processes and fate are poorly understood. The present study revealed the spatial heterogeneity and seasonal variations of traditional and novel OPEs in PM₂.₅ (particulate matter with diameters < 2.5 μm) across a megacity (including residential areas and potential source sites) in South China. Potential influencing factors on the contamination levels of OPEs were addressed. The total concentrations of 11 traditional OPEs ranging from 262 to 42,194 pg/m³ (median = 1872 pg/m³) were substantially higher than those of 10 novel OPEs (33.5–3835 pg/m³, median = 318 pg/m³). Significant spatial and temporal variations in the concentrations of most OPEs were observed. The overall district-specific contamination levels in this city showed dependence on the secondary industry sector for non-predominant OPEs and on the tertiary industry for predominant OPEs. The seasonal variations of the OPE concentrations suggest difference in their sources or influence of meteorological conditions. The correlations between the individual OPEs in PM₂.₅ are determined largely by either their applications or physicochemical properties (in particular vapor pressure). The correlations between OPE concentrations and each meteorological factor (temperature, relative humidity, wind speed, and surface solar radiation) were inconsistent (positive and negative). Wind speed had the greatest effect on the OPE levels; While most OPEs bound to PM₂.₅ were not efficiently scavenged by below-cloud rainfall. The results suggest that atmospheric half-life and Henry’s Law Constant of OPEs are also determining factors for the wind speed and rainfall influence, respectively. However, mechanisms underlying the influence of meteorological conditions on atmospheric OPEs still need further research.
Afficher plus [+] Moins [-]The effect of earthworms on plant response in metal contaminated soil focusing on belowground-aboveground relationships Texte intégral
2021
The effect of earthworms on plant response in metal contaminated soil focusing on belowground-aboveground relationships Texte intégral
2021
Contaminated soils are lands in Europe deemed less favourable for conventional agriculture. To overcome the problem of their poor fertility, bio-fertilization could be a promising approach. Soil inoculation with a choice of biological species (e.g. earthworm, mycorrhizal fungi, diazotroph bacteria) can be performed in order to improve soil properties and promote nutrients recycling. However, questions arise concerning the dynamics of the contaminants in an inoculated soil.The aim of this study was to highlight the soil-plant-earthworm interactions in the case of a slightly contaminated soil. For this purpose, a pot experiment in controlled conditions was carried out during 2 months with a Cd, Zn, and Cu contaminated sandy soil, including conditions with or without earthworms (Aporrectodea caliginosa) and with or without plants (Lolium perenne).The three components of the trace element bioavailability were studied to understand the belowground-aboveground relationships and were quantified as followed: i) environmental availability in soils by measuring trace element concentrations in soil solution, ii) environmental bioavailability for organisms by measuring trace element concentrations in depurated whole earthworms bodies and in the plant aerial biomass, and iii) toxicological bioavailability, by measuring survival rate and body weight changes for earthworms and biomass for plants. The results showed that earthworm inoculation increased the content of all studied TE in soil solution. Moreover, lower concentrations of Cd and Zn were found in plants in the presence of earthworms while the bioavailability decreased when compared to the condition without plants. The trace element bioaccumulation in earthworms did not produce a direct toxicity, according to the earthworm survival rate and body weight results.Finally, our pot experiment confirmed that even in contaminated soils, the presence of A. caliginosa promotes plant adaptation and improves biomass production, reducing trace element uptake.
Afficher plus [+] Moins [-]The effect of earthworms on plant response in metal contaminated soil focusing on belowground-aboveground relationships Texte intégral
2021
Hullot, Olivier | Lamy, Isabelle | Tiziani, Raphael | Mimmo, Tanja | Ciadamidaro, Lisa
Contaminated soils are lands in Europe deemed less favourable for conventional agriculture. To overcome the problem of their poor fertility, bio-fertilization could be a promising approach. Soil inoculation with a choice of biological species (e.g. earthworm, mycorrhizal fungi, diazotroph bacteria) can be performed in order to improve soil properties and promote nutrients recycling. However, questions arise concerning the dynamics of the contaminants in an inoculated soil. The aim of this study was to highlight the soil-plant-earthworm interactions in the case of a slightly contaminated soil. For this purpose, a pot experiment in controlled conditions was carried out during 2 months with a Cd, Zn, and Cu contaminated sandy soil, including conditions with or without earthworms (Aporrectodea caliginosa) and with or without plants (Lolium perenne). The three components of the trace element bioavailability were studied to understand the belowground-aboveground relationships and were quantified as followed: i) environmental availability in soils by measuring trace element concentrations in soil solution, ii) environmental bioavailability for organisms by measuring trace element concentrations in depurated whole earthworms bodies and in the plant aerial biomass, and iii) toxicological bioavailability, by measuring survival rate and body weight changes for earthworms and biomass for plants. The results showed that earthworm inoculation increased the content of all studied TE in soil solution. Moreover, lower concentrations of Cd and Zn were found in plants in the presence of earthworms while the bioavailability decreased when compared to the condition without plants. The trace element bioaccumulation in earthworms did not produce a direct toxicity, according to the earthworm survival rate and body weight results. Finally, our pot experiment confirmed that even in contaminated soils, the presence of A. caliginosa promotes plant adaptation and improves biomass production, reducing trace element uptake.
Afficher plus [+] Moins [-]The effect of earthworms on plant response in metal contaminated soil focusing on belowground-aboveground relationships Texte intégral
2021
Hullot, Olivier | Lamy, Isabelle | Tiziani, Raphael | Mimmo, Tanja | Ciadamidaro, Lisa | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Free University of Bozen-Bolzano | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | MAGIC project - European Union's Horizon 2020 research and innovation program
International audience | Contaminated soils are lands in Europe deemed less favourable for conventional agriculture. To overcome the problem of their poor fertility, bio-fertilization could be a promising approach. Soil inoculation with a choice of biological species (e.g. earthworm, mycorrhizal fungi, diazotroph bacteria) can be performed in order to improve soil properties and promote nutrients recycling. However, questions arise concerning the dynamics of the contaminants in an inoculated soil. The aim of this study was to highlight the soil-plant-earthworm interactions in the case of a slightly contaminated soil. For this purpose, a pot experiment in controlled conditions was carried out during 2 months with a Cd, Zn, and Cu contaminated sandy soil, including conditions with or without earthworms (Aporrectodea caliginosa) and with or without plants (Lolium perenne). The three components of the trace element bioavailability were studied to understand the belowground-aboveground relationships and were quantified as followed: i) environmental availability in soils by measuring trace element concentrations in soil solution, ii) environmental bioavailability for organisms by measuring trace element concentrations in depurated whole earthworms bodies and in the plant aerial biomass, and iii) toxicological bioavailability, by measuring survival rate and body weight changes for earthworms and biomass for plants. The results showed that earthworm inoculation increased the content of all studied TE in soil solution. Moreover, lower concentrations of Cd and Zn were found in plants in the presence of earthworms while the bioavailability decreased when compared to the condition without plants. The trace element bioaccumulation in earthworms did not produce a direct toxicity, according to the earthworm survival rate and body weight results. Finally, our pot experiment confirmed that even in contaminated soils, the presence of A. caliginosa promotes plant adaptation and improves biomass production, reducing trace element uptake.
Afficher plus [+] Moins [-]PAHs and their hydroxylated metabolites in the human fingernails from e-waste dismantlers: Implications for human non-invasive biomonitoring and exposure Texte intégral
2021
Ma, Shengtao | Zeng, Zihuan | Lin, Meiqing | Tang, Jian | Yang, Yan | Yu, Yingxin | Li, Guiying | An, Taicheng
Non-invasive human biomonitoring methods using hair and fingernails as matrices are widely used to assess the exposure of organic contaminants. In this work, a total of 72 human fingernails were collected from workers and near-by residents from a typical electronic waste (e-waste) dismantling site, and were analyzed for human exposure to polycyclic aromatic hydrocarbons (PAHs) and their mono-hydroxyl metabolites (OH-PAHs). The concentrations of PAHs and OH-PAHs were obtained as 7.97–551 and 39.5–3280 ng/g for e-waste workers (EW workers), 7.05–431 and 27.3–3320 ng/g for non-EW workers, 7.93–289 and 124–779 ng/g for adult residents, and 8.88–1280 and 181–293 ng/g for child residents, respectively. The composition profiles of PAHs in the human fingernails of the four groups were similar, with isomers of Phe, Pyr and Fluo being the predominated congeners, while 2-OH-Nap accounted for more than 70% of the total OH-PAHs. These contaminants were found most in the fingernails of EW workers, followed by non-EW workers, adult residents, and child residents, indicating e-waste dismantling activities are the major sources of PAH exposure. However, significantly higher levels of PAHs with 4–6 rings were observed only in workers as opposed to the residents, and a significant correlation between 3-OH-Flu (p < 0.05) and 2-OH-Phe (p < 0.01) in the fingernails and urine was observed, but no significant correlation was found between the concentration of OH-PAHs in matched hair and fingernail samples. In addition, the levels of PAHs in fingernails increased with the age of EW workers. This is the first study to explore the accumulation and distribution of PAHs and OH-PAHs in human fingernails, which would provide valuable insight into non-invasive biomonitoring and health risk assessment of PAHs.
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