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Radiocesium concentrations in invertebrates and their environmental media at two distances from the Fukushima Dai-ichi Nuclear Power Plant during 3–6 years after the 2011 accident 全文
2020
Iwasa, Mitsuhiro | Nakaya, Fumiya | Kabeya, Hideyuki | Sato, Kosuke | Ishikawa, Shin'ichirō | Takahashi, Teppei
Activity concentrations of the radioactive cesium (¹³⁴Cs and ¹³⁷Cs) were investigated in invertebrates at two sites of moderately high and higher air radiation dose rates, 14 km and 11 km distances, respectively, from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) from 2013 to 2016. At a14-km point, the ¹³⁴⁺¹³⁷Cs concentrations of soils in coniferous and broadleaf forests increased from 2013 to 2014, and thereafter declined until 2016. The ¹³⁴⁺¹³⁷Cs concentrations of the phytophagous beetle Anomala cuprea (Hope) rapidly decreased by 76.1% from 2013 to 2014, reflecting reduction in those of broadleaves. The ¹³⁴⁺¹³⁷Cs concentration levels of the carnivorous beetle Dolichus halensis (Schaller) showed a relatively low levels. The ¹³⁷Cs concentrations of the necrophagous beetle Eusilpha japonica (Motshulsky) and coprophagous beetle Onthophagus lenzii (Harold) remained constant without reduction from 2013 to 2016. Average ¹³⁴⁺¹³⁷Cs concentrations throughout four years were the highest in the geophagous crustacean (Armadillidium vulgare Latreille), followed by necrophagous beetle and coprophagus beetle. The ¹³⁴⁺¹³⁷Cs concentrations in earthworms with gut contents were significantly correlated with those in soils at each habitat from 2014 to 2015 at a14-km point, and the concentration levels at an 11-km point in 2015 were remarkably high (898 kBq kg⁻¹). Transfer factors (TFs) in earthworms ranged from 1.02 to 2.66 at a 14-km point and 0.66 to 5.0 at an11-km point. The transfer and chronological changes of radiocesium in invertebrates were discussed in relation to food habits through trophic levels in woodlands and pasturelands.
显示更多 [+] 显示较少 [-]Toxic effects and mechanisms of three commonly used fungicides on the human colon adenocarcinoma cell line Caco-2 全文
2020
Tao, Huaping | Bao, Zhiwei | Jin, Cuiyuan | Miao, Wenyu | Fu, Zhengwei | Jin, Yuanxiang
Fungicides, usually refer to the chemical agents that can effectively control or kill the pathogenic microorganisms. Here, we revealed the effects of three different fungicides, imazalil (IMZ), chlorothalonil (CTL) and carbendazim (CBZ), which are typical broad-spectrum fungicides that are detected at high levels in the natural environment, on heterogeneous human epithelial colorectal cells (Caco-2 cells). All three fungicides had the potential to induce different degrees of toxicity, cause apoptosis, reactive oxygen species (ROS) and even change the cell cycle in the cells. The half maximal inhibitory concentration (IC50) of CTL is the lowest among these three fungicides, suggesting that it may have the highest exposure risk, followed by IMZ, and CBZ. The results of the real-time PCR, Western blotting, and mitochondrial membrane potential (MMP) assays and the activities of key enzymes suggested that CTL induced apoptosis in Caco-2 cells via a mitochondrial-dependent pathway, as indicated by the upregulation of the expression of the apoptotic p53 and bax genes, the increase of the apoptosis marker cytochrome-c, the decrease of mRNA level of bcl-2 gene, and the decrease in the MMP. Exposure to two other fungicides also upregulated the transcriptional level of bax and the expression of cytochrome-c, but the mRNA level of bcl-2 was increased (IMZ) or unchanged (CBZ), suggesting that other pathways may be involved in the induction of cellular apoptosis by these two fungicides. In addition, all three of the fungicides could induce oxidative stress in Caco-2 cells. Our data showed that the three different kinds of fungicides all caused toxic effects in Caco-2 cells through various pathways.
显示更多 [+] 显示较少 [-]Mitigation effects of CO2-driven ocean acidification on Cd toxicity to the marine diatom Skeletonema costatum 全文
2020
Dong, Fang | Wang, Pu | Qian, Wei | Tang, Xing | Zhu, Xiaoshan | Wang, Zhenyu | Cai, Zhonghua | Wang, Jiangxin
Ocean acidification (OA) is a global problem to marine ecosystems. Cadmium (Cd) is a typical metal pollutant, which is non-essential but extremely toxic to marine organisms. The combined effects of marine pollution and climate-driven ocean changes should be considered for the effective marine ecosystem management of coastal areas. Previous reports have separately investigated the influences of OA and Cd pollution on marine organisms. However, little is known of the potential combined effects of OA and Cd pollution on marine diatoms. We investigated the sole and combined influences of OA (1500 ppm CO₂) and Cd exposure (0.4 and 1.2 mg/L) on the coastal diatom Skeletonema costatum. Our results clearly showed that OA significantly alleviated the toxicity of Cd to S. costatum growth and mitigated the oxidant stress, although the intercellular Cd accumulation still increased. OA partially rescued S. costatum from the inhibition of photosynthesis and pyruvate metabolism caused by Cd exposure. It also upregulated genes involved in gluconeogenesis, glycolysis, the citrate cycle (TCA), Ribonucleic acid (RNA) metabolism, and especially the biosynthesis of non-protein thiol compounds. These changes might contribute to algal growth and Cd resistance. Overall, this study demonstrates that OA can alleviate Cd toxicity to S. costatum and explores the potential underlying mechanisms at both the cellular and molecular levels. These results will ultimately help us understand the impacts of combined stresses of climate change and metal pollution on marine organisms and expand the knowledge of the ecological risks of OA.
显示更多 [+] 显示较少 [-]Impacts of electrokinetic isolation of phosphorus through pore water drainage on sediment phosphorus storage dynamics 全文
2020
Tang, Xianqiang | Li, Rui | Hinton, William | Wu, Xingyi
Pore water is a crucial storage medium and a key source of sediment phosphorus. A novel equipment based on electrokinetic geosynthetics (EKGs) was used for isolating phosphorus from eutrophic lake sediments through pore water drainage. Three mutually independent indoor group experiments (A, B, and C) were conducted to investigate the effects of voltage gradient (0.00, 0.25, and 0.50 V/cm) on pore water drainage capacity, phosphorus removal performance, sediment physicochemical properties, and phosphorus storage dynamics. The average reduction in the sediment moisture and total phosphorus content was 2.5%, 4.3%, and 4.6% and 28.15, 75.95, and 112.65 mg/kg after 6 days of treatment for A, B and C, respectively. Efficient pore water drainage through gravity and electroosmotic flow and electromigration of phosphate were the main drivers of sediment-dissolved and mobilized phosphorus separation. A high voltage gradient facilitated the migration of pore water and the phosphorus in it. The maximal effluent total phosphorous (TP) concentration was up to 27.9 times that in the initial pore water samples, and negligible effluent TP was detected when the pore water pH was less than 2.5. The TP concentration was exponentially and linearly related to the pH and electronic conductivity of the electroosmotic flow, respectively. The migration of H⁺ within the sediment matrix promoted the liberation of metals bounded to phosphorus, particularly of Ca–P and Fe–P. Pore water drainage through an EKG resulted in Ex–P separation of up to 87.50% and a 13.84 mg/kg decrease in Ca–P and 125.35 mg/kg accumulation of low mobile Fe–P in the weak acid anode zone.
显示更多 [+] 显示较少 [-]Effectiveness of melatonin to restore fish brain activity in face of permethrin induced toxicity 全文
2020
Moniruzzaman, Mahammed | Mukherjee, Mainak | Das, Debjit | Chakraborty, Suman Bhusan
Present study demonstrates permethrin induced oxidative damage in fish brain and explores effectiveness of melatonin to ameliorate brain function. Adult female Notopterus notopterus were exposed to nominal permethrin concentrations at 1/20th (0.34 μg/l) and 1/10th (0.68 μg/l) of LC₅₀ for 15 days. The measured permethrin concentrations using gas chromatography (GC-ECD) were 0.28 μg/l and 0.57 μg/l, respectively. Some fish were sacrificed to collect brain tissue after 15 days of exposure. Remaining fish from both groups were administered exogenous melatonin (50 μg/kg, 100 μg/kg body weight) for 7 days and brain tissues were collected. Brain enzymes, ntioxidant factors, HSP70, HSP90, nuclear factor-kappa binding (NFkB), melatonin receptor (MT1R) proteins were measured. Permethrin treatment significantly (P < 0.05) decreased the levels of glutathione and brain enzymes. Malondialdehyde (MDA), xanthine oxidase (XO), HSPs increased at each concentration of permethrin. However, superoxide dismutase, glutathione s-transferase levels increased at low permethrin concentration followed by sharp decrease at higher concentration. Expression of NFkB and MT1R increased significantly (P < 0.05). Melatonin administration reinstated activity of brain enzymes, reduced MDA, XO levels and modulated HSPs. Melatonin also increased expression of NFkB and MT1R. Exogenous melatonin improves oxidative status in permethrin stressed fish brain. Melatonin modulates expression of HSPs that enables brain to become stress tolerant and survive by initiating NFkB translocation. Melatonin could act through melatonin receptor protein to induce synthesis of antioxidant proteins. Therefore the study successfully evaluates the potential of melatonin application for better culture and management of fish against pesticide toxicity.
显示更多 [+] 显示较少 [-]Human health risk assessment of some bottled waters from Romania 全文
2020
Dippong, Thomas | Hoaghia, Maria-Alexandra | Mihali, Cristina | Cical, Elena | Calugaru, Mihai
The paper presents the quality status of 14 brands of bottled water, with sources of groundwaters from different mountain areas alongside the Carpathian Mountains from Romania. A number of 12 physico-chemical parameters (ammonium, bicarbonate, electrical conductivity, carbonate, chemical oxygen demand, chloride, nitrate, nitrite, pH, sulphate, total hardness, turbidity), 9 metals and metalloids (Li, B, Na, Mg, Al, K, Ca, Sr, Ba) and 17 heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Mo, Ag, Cd, In, Tl, Pb, Bi) were determined and studied. The quality status, the potential contamination and the health risk assessment of bottled waters were assessed, by using the drinking water quality index, the heavy metal pollution index, the heavy metal evaluation index, the degree of contamination and the human health risk indices. Hierarchical cluster analysis was applied, indicating similarities among the studied bottled waters based on their metal content. The Piper diagram reveals that the majority of bottled water samples fall into the Ca, Mg, Na, K, Cl⁻, SO₄²⁻, CO₃²⁻, HCO₃⁻ categories. The quality of bottled waters based on the indices results indicated marginal, poor and very-poor quality status of the studied water samples, while the health risk assessment indices presented potential risks at aluminium, chloride and nitrate for the inhabitants who used those water samples with the purpose of drinking. The pollution indices with respect to metals generally reflected a low pollution status. This study represents the first attempt in assessing the overall quality of some bottled water collected from the mountain area, Romania, likewise assessing the comprehensive human health risk due to several chemical elements determined in water in amounts around and exceeding the maximum allowable concentrations. This research can be useful for development of potential strategies for risk control and management in the field of drinking water.
显示更多 [+] 显示较少 [-]Variations of PCDD/Fs emissions from secondary nonferrous smelting plants and towards to their source emission reduction 全文
2020
Yang, Yuanping | Wu, Guanglong | Jiang, Cheng | Zheng, Minghui | Yang, Lili | Xie, Jiahong | Wang, Qingjie | Wang, Minxiang | Li, Cui | Liu, Guorui
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are cancerogenic organic pollutants that priority controlled by Stockholm Convention with globally 183 signatories now. Secondary nonferrous smelting plants are confirmed to be important sources in China due to its large industrial activities and high emissions of PCDD/Fs. It is important to prioritize source to achieve source emission reduction by conducting field monitoring on typical case plants. Here, the emission profiles and levels of PCDD/Fs were investigated in 25 stack gas samples collected from three secondary copper production (SeCu), two secondary zinc production (SeZn) and two secondary lead production (SePb). Both average mass concentration and toxic equivalency quantity (TEQ) concentrations of PCDD/Fs all generally decreased in the order: SeCu > SeZn > SePb. It is noteworthy that the mean TEQ concentration in stack gas from SeCu with oxygen-enrich melting furnace technology, at 2.7 ng I-TEQ/Nm³, was much higher than the concentrations of other smelting processes. The average emission factors and annual release amounts of PCDD/Fs from SeCu, SePb and SeZn investigated were 28.4, 1.5, 10.4 μg I-TEQ/t and 1.03, 0.023, 0.17 g I-TEQ/year, respectively. The ratios of 2,3,7,8-TCDF to 1,2,3,7,8-PeCDF and OCDD to 1,2,3,7,8,9-HxCDD varied to large extent for three metal smelting, which could be used as diagnostic ratios of tracing specific PCDD/Fs sources. Addition of copper-containing sludge into the raw materials might lead to higher PCDD/Fs emissions. It is important to emphasize and reduce the PCDD/Fs emissions from oxygen-enrich melting furnace from secondary copper productions.
显示更多 [+] 显示较少 [-]Urinary concentrations of phthalates in relation to circulating fatty acid profile in National Health and Nutrition Examination Survey, 2003–2004 and 2011–2012 全文
2020
Li, Ming-Chieh | Lin, Jingyu | Guo, Yue Leon
Animal studies have suggested that phthalate exposure alters the fatty acid composition of blood plasma. Therefore, we conducted an epidemiological study to examine whether urinary concentrations of phthalates are correlated with circulating fatty acids in the general US population. The 2003–2004 and 2011–2012 National Health and Nutrition Examination Survey were used in this study. Ten urinary phthalate metabolites and 23 fatty acids were measured. Fatty acid patterns were identified using principal component analysis (PCA) with an eigenvalue greater than 1. A two-step analysis was performed. We first performed multivariable linear regressions to evaluate whether urinary phthalate metabolites were related to the PCA-derived components of blood fatty acid levels. Then we performed multivariable linear regressions to investigate each of the fatty acids that were suggestively correlated with some of the phthalates in PCA. There were 994 participants (51.91% women). As for men, after adjustments for potential confounding factors, MECPP, MEHHP, and ∑DEHP were all positively correlated with gamma-linolenic, myristoleic, and myristic acids; both MEHHP and ∑DEHP were positively correlated with stearic acid; MMP was positively correlated with docosahexaenoic acid. As for women, MMP was negatively correlated with docosanoic, lignoceric, and arachidic acids; MBzP was negatively correlated with docosahexaenoic acid; both MEHP and MCPP were negatively correlated with docosatetraenoic acid; MEHP was negatively correlated with arachidonic acid, and MCPP was negatively correlated with docosapentaenoic-6 acid. Our findings support that phthalates may be correlated with circulating fatty acids.
显示更多 [+] 显示较少 [-]Maternal exposure to ambient air pollution during pregnancy and lipid profile in umbilical cord blood samples; a cross-sectional study 全文
2020
Heydari, Hafez | Abroudi, Mina | Adli, Abolfazl | Pirooznia, Nazanin | Najafi, Moslem Lari | Pajohanfar, Nasim Sadat | Dadvand, Payam | Miri, Mohammad
Adverse health effects of exposure to air pollution have been investigated in many previous studies. However, there is no study available on the association between maternal exposure to air pollution during pregnancy and cord blood lipid profile. This study, based on 150 mother-newborn pairs residing in Sabzevar, Iran (2018), evaluated the association of exposure to ambient air pollution as well as traffic indicators (total street length in different buffers around residential address and distance to major roads) during entire pregnancy with lipid levels cord blood lipid profile. Concentrations of PM₁₀, PM₂.₅, and PM₁ at maternal residential address were estimated using land use regression (LUR) models. We measured triglyceride (TAG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC) levels and TC/HDL-C and TAG/HDL-C ratio in the cord blood samples to characterize their lipid profile. Multiple linear regression models were developed to estimate the association of exposure to air pollution and traffic indicators with cord blood lipid profile controlled for relevant covariates. Higher concentrations of PM₂.₅ and PM₁₀ were associated with higher levels of TAG, TC, HDL-C, TC/HDL-C, and TAG/HDL-C in cord blood samples. Moreover, higher concentration of PM₁ was associated with higher levels of TAG, TC and LDL-C. There was also a positive association between total street length in 100 m buffer around home and serum levels of TC, TAG, LDL-C and TC/HDL ratio (β = 3.73, 95% confidence intervals (CI): 1.76, 5.71; β = 2.75, 95% CI: 0.97, 4.53; β = 1.87, 95% CI: 0.64, 3.09; β = 0.06, 95% CI: 0.01, 0.11, respectively). However, the associations for total street length in larger buffers and distance to major roads were not statistically significant. Our findings support a relationship between exposure to air pollution during pregnancy and increase in cord blood lipid levels.
显示更多 [+] 显示较少 [-]Elements in surface and well water from the central North China Plain: Enrichment patterns, origins, and health risk assessment 全文
2020
Long, Jie | Luo, Kunli
The principal aim of this study was to understand the enrichment patterns of elements in water from typical coal mine and irrigation areas. For this study, samples of surface water, shallow water, and deep water were collected from Handan, Jining, and Heze cities and their surrounding areas in the central North China Plain. The results showed that the hydrochemical characteristics were dominated by Ca–Mg–Cl and Ca–HCO₃. Elements in the studied surface water, including strontium, iron and boron, were anomalously enriched at levels more than 654, 294 and 134 times their global river water averages, respectively. The concentrations of elements in the studied area were influenced by both natural processes and anthropogenic sources, but the dominant origins of the anomalous enriched elements were bedrock weathering and soil leaching. The deep well water quality in the Handan coal mining area was good, while the poor-quality water samples in the study area were mainly distributed in the alluvial plain, which is characterized by Neogene-Quaternary sediments and aquifers. The measured hazard quotient and hazard index values indicate that the arsenic and nickel in the studied samples could pose a noncarcinogenic risk to the health of local residents, especially children. The leading source of the high arsenic levels is influenced by natural process. Monitoring plans for arsenic, iron, manganese, nitrate and other potentially harmful elements in surface water and groundwater and effective health education on pollution by these elements are essential.
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