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Glyphosate exposure induces inflammatory responses in the small intestine and alters gut microbial composition in rats
2020
Tang, Qian | Tang, Juan | Ren, Xin | Li, Chunmei
Glyphosate is the most popular herbicide used worldwide. This study aimed to investigate the adverse effects of glyphosate on the small intestine and gut microbiota in rats. The rats were gavaged with 0, 5, 50, and 500 mg/kg of body weight glyphosate for 35 continuous days. The different segments of the small intestine were sampled to measure indicators of oxidative stress, ion concentrations and inflammatory responses, and fresh feces were collected for microbiota analysis. The results showed that glyphosate exposure decreased the ratio of villus height to crypt depth in the duodenum and jejunum. Decreased activity of antioxidant enzymes (T-SOD, GSH, GSH-Px) and elevated MDA content were observed in different segments of the small intestine. Furthermore, the concentrations of Fe, Cu, Zn and Mg were significantly decreased or increased. In addition, the mRNA expression levels of IL-1β, IL-6, TNF-α, MAPK3, NF-κB, and Caspase-3 were increased after glyphosate exposure. The 16 S rRNA gene sequencing results indicated that glyphosate exposure significantly increased α-diversity and altered bacterial composition. Glyphosate exposure significantly decreased the relative abundance of the phylum Firmicutes and the genus Lactobacillus, but several potentially pathogenic bacteria were enriched. In conclusion, this study provides important insight to reveal the negative influence of glyphosate exposure on the small intestine, and the altered microbial composition may play a vital role in the process.
显示更多 [+] 显示较少 [-]Linking elevated blood lead level in urban school-aged children with bioaccessible lead in neighborhood soil
2020
Wu, Yangyang | Lou, Jianing | Sun, Xue | Ma, Lena Q. | Wang, Jueyang | Li, Mengya | Sun, Hong | Li, Hongbo | Huang, Lei
Lead (Pb) exposure is known to affect the health of children while soil Pb is an important contributor to human Pb exposure. To analyze the effects of both environmental and other factors, especially total and bioaccessible Pb in neighborhood soil, on school-aged urban children’s blood lead level (BLL), 75 children (6–11 years old) were recruited from an industry city in eastern China for BLL measurement and questionnaire survey. Soil samples were collected from their living neighborhoods and measured for total and bioaccessible Pb. The mean BLL was 4.82 μg dL⁻¹, with 42 out of 75 children having BLL exceeding the international guideline of 5 μg dL⁻¹. Low Pb contamination was observed in soil with total Pb ranging from 12.5 to 271 mg kg⁻¹ (mean 34.3 mg kg⁻¹). Based on the in vitro Solubility Bioaccessibility Research Consortium (SBRC) gastric fluid extraction, bioaccessible Pb in soil ranged from 0.40 to 79.1 mg kg⁻¹ (mean 7.58 mg kg⁻¹) with Pb bioaccessibility ranging from 1.74 to 68.1 (mean 19.9%). When BLL was correlated with total Pb in soil, insignificant linear relationship was observed (P > 0.05, correlation coefficient 95%CI = −0.047–0.40, R² = 0.07). However, when BLL was correlated with soil bioaccessible Pb or Pb bioaccessibility, much stronger linear relationships were observed (P < 0.01, correlation coefficient 95%CI = 0.28–0.64, R² = 0.16–0.20), suggesting that bioaccessible Pb was a much stronger predictor of BLL. In addition, strong associations were also observed between BLL and social factors such as house decoration, residence time, and personal habits, suggesting that both soil Pb contamination and social factors play important roles in elevating BLL for city children.
显示更多 [+] 显示较少 [-]The fate of cigarette butts in different environments: Decay rate, chemical changes and ecotoxicity revealed by a 5-years decomposition experiment
2020
Bonanomi, Giuliano | Maisto, Giulia | De Marco, Anna | Cesarano, Gaspare | Zotti, Maurizio | Mazzei, Pierluigi | Libralato, Giovanni | Staropoli, Alessia | Siciliano, Antonietta | De Filippis, Francesca | La Storia, Antonietta | Piccolo, Alessandro | Vinale, Francesco | Crasto, Antonio | Guida, Marco | Ercolini, Danilo | Incerti, Guido
Cigarette butts (CBs) are the most common litter item on Earth but no long-term studies evaluate their fate and ecological effects. Here, the role of nitrogen (N) availability and microbiome composition on CBs decomposition were investigated by a 5-years experiment carried out without soil, in park grassland and sand dune. During decomposition, CBs chemical changes was assessed by both ¹³C CPMAS NMR and LC-MS, physical structure by scanning electron microscope and ecotoxicity by Aliivibrio fischeri and Raphidocelis subcapitata. Microbiota was investigated by high-throughput sequencing of bacterial and eukaryotic rRNA gene markers. CBs followed a three-step decomposition process: at the early stage (∼30 days) CBs lost ∼15.2% of their mass. During the subsequent two years CBs decomposed very slowly, taking thereafter different trajectories depending on N availability and microbiome composition. Without soil CBs showed minor chemical and morphological changes. Over grassland soil a consistent N transfer occurs that, after de-acetylation, promote CBs transformation into an amorphous material rich in aliphatic compounds. In sand dune we found a rich fungal microbiota able to decompose CBs, even before the occurrence of de-acetylation. CBs ecotoxicity was highest immediately after smoking. However, for R. subcapitata toxicity remained high after two and five years of decomposition.
显示更多 [+] 显示较少 [-]Sewage sludge application as a vehicle for microplastics in eastern Spanish agricultural soils
2020
van den Berg, Pim | Huerta-Lwanga, Esperanza | Corradini, Fabio | Geissen, Violette
Microplastic pollution is becoming a major challenge with the growing use of plastic. In recent years, research about microplastic pollution in the environment has become a field of study with increased interest, with ever expanding findings on sources, sinks and pathways of microplastics. Wastewater treatment plants effectively remove microplastics from wastewater and concentrate them in sewage sludge which is often used to fertilise agricultural fields. Despite this, quantification of microplastic pollution in agricultural fields through the application of sewage sludge is largely unknown. In light of this issue, four wastewater treatment plants and 16 agricultural fields (0–8 sewage sludge applications of 20–22 tons ha⁻¹ per application), located in the east of Spain, were sampled. Microplastics were extracted using a floatation and filtration method, making a distinction between light density microplastics (ρ < 1 g cm⁻³) and heavy density microplastics (ρ > 1 g cm⁻³). Sewage sludge, on average, had a light density plastic load of 18,000 ± 15,940 microplastics kg⁻¹ and a heavy density plastic load of 32,070 ± 19,080 microplastics kg⁻¹. Soils without addition of sewage sludge had an average light density plastic load of 930 ± 740 microplastics kg⁻¹ and a heavy density plastic load of 1100 ± 570 microplastics kg⁻¹. Soils with addition of sewage sludge had an average light density plastic load of 2130 ± 950 microplastics kg⁻¹ and a heavy density plastic load of 3060 ± 1680 microplastics kg⁻¹. On average, soils’ plastic loads increased by 280 light density microplastics kg⁻¹ and 430 heavy density microplastics kg⁻¹ with each successive application of sewage sludge, indicating that sewage sludge application results in accumulation of microplastics in agricultural soils.
显示更多 [+] 显示较少 [-]Metal-organic framework MIL-100(Fe) for dye removal in aqueous solutions: Prediction by artificial neural network and response surface methodology modeling
2020
Jang, Ho-Young | Kang, Jin-Kyu | Park, Jeong-Ann | Lee, Seung-Chan | Kim, Sŏng-bae
In this study, a metal organic framework MIL-100(Fe) was synthesized for rhodamine B (RB) removal from aqueous solutions. An experimental design was conducted using a central composite design (CCD) method to obtain the RB adsorption data (n = 30) from batch experiments. In the CCD approach, solution pH, adsorbent dose, and initial RB concentration were included as input variables, whereas RB removal rate was employed as an output variable. Response surface methodology (RSM) and artificial neural network (ANN) modeling were performed using the adsorption data. In RSM modeling, the cubic regression model was developed, which was adequate to describe the RB adsorption according to analysis of variance. Meanwhile, the ANN model with the topology of 3:8:1 (three input variables, eight neurons in one hidden layer, and one output variable) was developed. In order to further compare the performance between the RSM and ANN models, additional adsorption data (n = 8) were produced under experimental conditions, which were randomly selected in the range of the input variables employed in the CCD matrix. The analysis showed that the ANN model (R² = 0.821) had better predictability than the RSM model (R² = 0.733) for the RB removal rate. Based on the ANN model, the optimum RB removal rate (>99.9%) was predicted at pH 5.3, adsorbent dose 2.0 g L−1, and initial RB concentration 73 mg L−1. In addition, pH was determined to be the most important input variable affecting the RB removal rate. This study demonstrated that the ANN model could be successfully employed to model and optimize RB adsorption to the MIL-100(Fe).
显示更多 [+] 显示较少 [-]Identification of microplastics in surface water and Australian freshwater shrimp Paratya australiensis in Victoria, Australia
2020
Nan, Bingxu | Su, Lei | Kellar, Claudette | Craig, Nicholas J. | Keough, Michael J. | Pettigrove, Vincent
Compared to marine microplastics research, few studies have bio-monitored microplastics in inland waters. It is also important to understand the microplastics’ uptake and their potential risks to freshwater species. The Australian glass shrimp Paratya australiensis (Family: Atyidae) is commonly found in fresh waterbodies in eastern Australia, and are sensitive to anthropogenic stressors but have a wide tolerance range to the natural environmental conditions. This study aimed to understand the microplastics’ occurrence and types in water samples and the shrimp P. australiensis, and identify if the shrimp could be a suitable bioindicator for microplastic pollution. Surface water and P. australiensis across ten urban and rural freshwater sites in Victoria were sampled. In total, 30 water samples and 100 shrimp were analysed for microplastic content, and shrimp body weights and sizes were also recorded. Microplastics were picked, photographed and identified using FT-IR microscopy: in water samples, 57.9% of items including suspect items were selected to identify; all microplastics found in shrimp samples were identified. Microplastics were present in the surface waters of all sites, with an average abundance of 0.40 ± 0.27 items/L. A total of 36% of shrimp contained microplastics with an average of 0.52 ± 0.55 items/ind (24 ± 31 items/g). Fibre was the most common shape, and blue was the most frequent colour in both water and shrimp samples. The dominant plastic types were polyester in water samples, and rayon in shrimp samples. Even though results from this study show a relatively low concentration of microplastics in water samples in comparison with global studies, it is worth noticing that microplastics were regularly detected in fresh waterbodies in Victoria, Australia. Compared with water samples, shrimp contained a wider variety of plastic types, suggesting they may potentially behave as passive samplers of microplastics pollution in freshwater environments.
显示更多 [+] 显示较少 [-]Polycyclic musks in surface water and sediments from an urban catchment in the megacity Beijing, China
2020
Zhang, Handan | Bu, Qingwei | Wu, Dongkui | Yu, Gang
Two typical polycyclic musks (PCMs), namely 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-(g)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), were determined in 63 surface water and 42 sediment samples collected from the North Canal River watershed, an urban catchment located in the megacity Beijing, China. Concentrations of HHCB and AHTN were 13.2 ng/L–395 ng/L and 2.98 ng/L–232 ng/L in surface water, while 4.10 ng/g–818 ng/g and 1.21 ng/g–731 ng/g in sediments. The results showed that PCM concentrations in the North Canal River watershed were at the high end when compared to that in other regions in China and worldwide. A watershed-wide annual mass budget showed that HHCB (∼150 kg/year) and AHTN (∼80 kg/year) mainly originated from urban wastewaters. Both PCMs were eliminated primarily by outflowing water (72 kg/year and 43 kg/year for HHCB and AHTN, respectively) and due to losses to the atmosphere (40 kg/year and 26 kg/year for HHCB and AHTN, respectively). An assessment of ecological risks posed by HHCB and AHTN to aquatic organisms in the North Canal River watershed was performed by using a tiered ecological risk assessment. The results showed that PCMs were unlikely to pose an ecological risk at the watershed scale (the probability of the incidence of adverse effect was <3.5% at the 99% protection level). However, according to the results from the risk quotient method, the tributaries draining wastewater effluents should be hotspots that warrant further research in future.
显示更多 [+] 显示较少 [-]Co-exposure to polycyclic aromatic hydrocarbons, benzene and toluene may impair lung function by increasing oxidative damage and airway inflammation in asthmatic children
2020
Kuang, Hongxuan | Liu, Jian | Zeng, Yingwei | Zhou, Wenji | Wu, Peiqiong | Tan, Jianhua | Li, Yonghong | Pang, Qihua | Jiang, Wenhui | Fan, Ruifang
As previous studies found that the direct associations between urinary polycyclic aromatic hydrocarbon (PAH), benzene and toluene (BT) metabolites and the decreased lung function were not conclusive, we further investigated relationship of oxidative damage and airway inflammation induced by PAHs and BTs exposure with lung function. A total of 262 children diagnosed with asthma and 72 heathy children were recruited. Results showed that asthmatic children had higher levels of PAHs and BTs exposure, as well as Malonaldehyde (MDA) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) compared with healthy children. Furthermore, binary logistic regression showed that each unit increases in level of urinary 2-&3-hydroxyfluorene (2-&3-OHF), 2-hydroxyphenanthrene (2-OHPhe), 1-hydroxyphenanthrene (1-OHP) and S-phenylmercapturic acid (S-PMA) were significantly associated with an elevated risk of asthma in children with odds ratios of 1.5, 2.3, 1.7 and 1.4, respectively, suggesting that PAHs and BTs exposure could increase the risk of asthma for children. Neither PAH nor BT metabolite could comprehensively indicate the decreased lung function as only 2-&3-OHF and 1-OHP were significantly and negatively correlated with forced vital capacity (FVC). Moreover, levels of most individual PAH and BT metabolite were significantly correlated to MDA and 8-OHdG. Further hierarchical regression analysis indicated that MDA and 8-OHdG levels did not show significant effects on the decreased lung function, suggesting that they are not the suitable biomarkers to indirectly indicate the altered lung function induced by PAHs and BTs. Urinary 2-OHPhe and 1-&9-hydroxyphenanthrene (1-&9-OHPhe) were significantly correlated with fractional exhaled nitric oxide (FeNO). Moreover, FeNO significantly contributed to decreased lung function and explained 7.7% of variance in ratio of forced expiratory volume in 1 s (FEV₁) and FVC (FEV₁/FVC%). Hence, FeNO, rather than oxidative damage indicators or any urinary PAH and BT metabolite, is more sensitive to indirectly reflect the decreased lung function induced by PAHs and BTs exposure for asthmatic children.
显示更多 [+] 显示较少 [-]Prenatal exposure to residential PM2.5 and anogenital distance in infants at birth: A birth cohort study from Shanghai, China
2020
Sun, Xiaowei | Liu, Cong | Wang, Ziliang | Yang, Fen | Liang, Hong | Miao, Maohua | Yuan, Wei | Kan, Haidong
Fine particulate matter (PM₂.₅) is believed to be one of the most hazardous air pollution with a ubiquitous presence. Animal studies have reported the association between prenatal exposure to traffic pollutant (not exclusively including PM₂.₅) and reproductive development in male offspring. However, the effects of prenatal exposure to PM₂.₅ on reproductive health in children are still unknown. The present study was based on the Shanghai-Minhang Birth Cohort Study (S-MBCS). A total of 876 pregnant women and their infants were included. Infants’ anogenital distance (AGD, the distance from the anus to the genitals; AGDap [anus-penis] and AGDas [anus-scrotum] for boys, and AGDac [anus-clitoris] and AGDaf [anus-fourchette] for girls) were measured at birth. PM₂.₅ concentrations during pregnancy were estimated using satellite based modeling approach. Multiple linear regression analysis and multiple informant model were conducted to examine the associations between prenatal exposure to PM₂.₅ (pre μg/m³) and offspring’s AGDs (mm). In order to minimize the misclassification of exposure, a sensitivity analysis restricted to mothers being off work during pregnancy was performed. In multiple linear regression models, we found that prenatal exposure to PM₂.₅ during the 1ˢᵗ and 3ʳᵈ trimesters was associated with shorter AGDs. In multiple informant model, similar patterns were found, and statistically significant reductions were observed in AGDap (β=−0.278, 95%CI: -0.343∼-0.212), AGDac (β=−0.188, 95%CI: -0.247∼-0.130) and AGDaf (β= −0.163, 95%CI: -0.238∼-0.088) with PM₂.₅ exposure during the 1ˢᵗ trimester, and AGDap (β=−0.201, 95%CI: -0.247∼-0.155), AGDas (β=−0.158, 95%CI: -0.198∼-0.117), AGDac (β=−0.128, 95%CI: -0.167∼-0.089) and AGDaf (β = −0.144, 95%CI: -0.194∼-0.094) with PM₂.₅ exposure during the 3ʳᵈ trimester. The sensitivity analysis restricted to women being off work during pregnancy showed similar results. PM₂.₅ exposure during the 1ˢᵗ and 3ʳᵈ trimesters was associated with shortened AGDs in offspring at birth. Our findings provide preliminary evidence that prenatal exposure to PM₂.₅ might be associated with the reproductive development of offspring.
显示更多 [+] 显示较少 [-]Advanced determination of the spatial gradient of human health risk and ecological risk from exposure to As, Cu, Pb, and Zn in soils near the Ventanas Industrial Complex (Puchuncaví, Chile)
2020
Tapia-Gatica, Jaime | González-Miranda, Isabel | Salgado, Eduardo | Bravo, Manuel A. | Tessini, Catherine | Dovletyarova, Elvira A. | Paltseva, Anna A. | Neaman, Alexander
The townships of Puchuncaví and Quintero, on the coast of central Chile, have soils contaminated by atmospheric deposition of sulfur dioxide and trace elements from the nearby Ventanas Industrial Complex. The purpose of this study was to evaluate potential human health and ecological risks, by determining the spatial distribution of soil total concentrations arsenic (As), copper (Cu), lead (Pb), and zinc (Zn) in these townships. Total concentrations of these elements were determined in 245 topsoil samples, used to generate continuous distribution maps. The background concentrations of Cu, As, Pb, and Zn in the studied soils were 100, 16, 35, and 122 mg kg⁻¹, respectively. The concentrations of Cu, As, and Pb were positively correlated with each other, suggesting that their source is the Ventanas copper smelter. On the other hand, correlations for Zn were weaker than for other trace elements, suggesting low impact of the Ventanas copper smelter on spatial distribution of Zn. Indeed, only 6% of the study area exhibited Zn concentrations above the background level. In contrast, 77, 32 and 35% of the study area presented Cu, As, and Pb concentrations, respectively, above the background level. The carcinogenic risk due to exposure to As was above the threshold value of 10⁻⁰⁴ in the population of young children (1–5 years old) on 27% of the study area. These risk values are classified as unacceptable, which require specific intervention by the Chilean government. Based on the estimated concentrations of exchangeable Cu, 10, 15, and 75% of the study area exhibited high, medium, and low phytotoxicity risk, respectively.
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