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Ecological and health risk assessments and water quality criteria of heavy metals in the Haihe River Full text
2021
Cui, Liang | Wang, Xiaonan | Li, Ji | Gao, Xiangyun | Zhang, Jiawen | Liu, Zhengtao
Heavy metal pollution is an issue of wide concern owing to the toxic and bioaccumulative properties of many heavy metals and their tendencies to persist in the environment. The Haihe River is an important river in the Beijing–Tianjin–Hebei region, and heavy metal pollution of the basin has attracted considerable attention. This study determined the concentrations of 14 heavy metals (As, Ba, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Se, Sn, and Zn) in water, sediments, and fish samples from the Haihe River basin. The results showed that the concentrations ranged from 0.08 μg L⁻¹ to 60.49 μg L⁻¹ in water, 0.11 mg kg⁻¹ to 229.20 mg kg⁻¹ in sediments, and 0.01 mg kg⁻¹ to 11.72 mg kg⁻¹ in fish. We derived the ambient water quality criteria (AWQC) value of each heavy metal with respect to human health, and then performed a comprehensive risk assessment according to the native parameters. The human health AWQC values for the assessed 14 heavy metals ranged from 0.16 μg L⁻¹ to 726.53 μg L⁻¹. The health risks posed by As, Cr, Hg, and Sb and the ecological risks associated with Ni, Cu, Cr, Zn, Cd, Co, Hg, and Sn were found to be issues of concern. The results of a sensitivity analysis revealed that the highest contributing parameter was i) the concentration in water (Cw) for Cd, Co, Mn, Sb, and Sn; ii) the intake rate of water (IRw) for As, Ba, Cr, Hg, Ni, Pb, and Se; and iii) the concentration in fish (Cf) for Cu and Zn. The results of this research could contribute to the information required for water quality assessments and the development of water quality standards.
Show more [+] Less [-]Cadmium promotes breast cancer cell proliferation, migration and invasion by inhibiting ACSS2/ATG5-mediated autophagy Full text
2021
Liang, Yidan | Pi, Huifeng | Liao, Lingzhi | Tan, Miduo | Deng, Ping | Yue, Yang | Xi, Yu | Tian, Li | Xie, Jia | Chen, Mengyan | Luo, Yan | Chen, Mingliang | Wang, Liting | Yu, Zhengping | Zhou, Zhou
Cadmium (Cd), which is considered a carcinogenic metal, promotes breast cancer (BC) progression, but the precise mechanism remains unclear. Herein, MCF-7 and T47-D cells were treated with 0.1, 1, and 10 μM cadmium chloride (CdCl₂) for 24, 48 and 72 h. In our study, Cd exposure significantly accelerated the proliferation, migration and invasion of MCF-7 and T47-D cells. Notably, Cd inhibited autophagic flux by suppressing ATG5-dependent autophagosome formation but had no significant effect on autophagosome-lysosome fusion and lysosomal function. The genetic enhancement of autophagy through ATG5 overexpression suppressed the Cd-mediated increases in proliferation, migration and invasion, which indicated a carcinogenic role of autophagy impairment in Cd-exposed BC cells. GSEA and GeneMANIA were utilized to demonstrate that the Cd-induced decrease in ACSS2 expression mechanistically inhibited ATG5-dependent autophagy in BC cells. Importantly, ACSS2 overexpression increased the level of H3K27 acetylation in the promoter region of ATG5, and this result maintained autophagic flux and abolished the Cd-induced increases in proliferation, migration and invasion. We also verified that the expression of ACSS2 in BC tissues was low and positively related to ATG5 expression. These findings indicated that the promoting effect of Cd on BC cell proliferation, migration and invasion through the impairment of ACSS2/ATG5-dependent autophagic flux suggests a new mechanism for BC cell proliferation and metastasis stimulated by Cd.
Show more [+] Less [-]Highly-efficient green photocatalytic cementitious materials with robust weathering resistance: From laboratory to application Full text
2021
Guo, Ming-Zhi | Ling, Tung-Chai | Poon, C. S. (Chi-sun)
The combined use of nano-TiO₂ with cementitious materials offers an environmentally-friendly way to combat the air pollution problem. However, a trade-off between a high efficiency and a robust weathering resistance has often to be made for most of the attempted nano-TiO₂ incorporation methods. This paper developed a simple and effective “spraying” method to coat nano-TiO₂ particles on the surface of concrete surface layers (CSL). The results showed that the NOₓ removal rate of the samples increased with an increase in both the concentrations of nano-TiO₂ solutions and the number of times of the spraying action. And the conditions for preparation of the Spray AB (the CSL were first sprayed with the 30 g L⁻¹ TiO₂-solution 20 times, followed by mechanical compaction, and for another 20 times after the compaction) were found to be optimal in terms of NOₓ removal performance and weathering resistance. The Spray AB was superior to the 5% TiO₂-intermixed samples with respect to photocatalytic NOₓ removal ability. Compared with TiO₂-dip-coated samples, the Spray AB samples had better and robust weathering resistance. A case study on the factory-fabricated green Eco-blocks (produced by the laboratory-developed spray method and the conventional intermix method) was performed. Examination and comparison on their respective photocatalytic NOₓ removal further verified the advantages of the spray method over the intermix method.
Show more [+] Less [-]The influence of industry-related air pollution on birth outcomes in an industrialized area Full text
2021
Bergstra, Arnold D. | Brunekreef, B. | Burdorf, Alex
Recent studies suggests that air pollution, from among others road traffic, can influence growth and development of the human foetus during pregnancy. The effects of air pollution from heavy industry on birth outcomes have been investigated scarcely.Our aim was to investigate the associations of air pollution from heavy industry on birth outcomes.A cross-sectional study was conducted among 4488 singleton live births (2012–2017) in the vicinity of a large industrial area in the Netherlands. Information from the birth registration was linked with a dispersion model to characterize annual individual-level exposure of pregnant mothers to air pollutants from industry in the area. Associations between particulate matter (PM₁₀), nitrogen oxides (NOX), sulphur dioxide (SO₂), and volatile organic compounds (VOC) with low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA) were investigated by logistic regression analysis and with gestational age, birth weight, birth length, and head circumference by linear regression analysis.Exposures to NOX, SO₂, and VOC (per interquartile range of 1.16, 0.42, and 0.97 μg/m³ respectively) during pregnancy were associated with LBW (OR 1.20, 95%CI 1.06–1.35, OR 1.20, 95%CI 1.00–1.43, and OR 1.21, 95%CI 1.08–1.35 respectively). NOX and VOC were also associated with PTB (OR 1.14, 95%CI 1.01–1.29 and OR 1.17, 95%CI 1.04–1.31 respectively). Associations between exposure to air pollution and birth weight, birth length, and head circumference were statistically significant. Higher exposure to PM₁₀, NOX, SO₂ and VOC (per interquartile range of 0.41, 1.16, 0.42, and 0.97 μg/m³ respectively) was associated with reduced birth weight of 21 g to 30 g.The 90th percentile industry-related PM₁₀ exposure corresponded with an average birth weight decrease of 74 g.
Show more [+] Less [-]Continuous increases of surface ozone and associated premature mortality growth in China during 2015–2019 Full text
2021
Maji, Kamal Jyoti | Namdeo, Anil
Ambient ozone (O₃) pollution has become a big issue in China. Recent studies have linked long- and short-term O₃ exposure to several public health risks. In this study, we (1) characterize the long-term and short-term O₃-attributed health metric in China from 2015 to 2019; (2) estimate the surface O₃ trends; and (3) quantify the long-term and short-term health impacts (i.e. all-cause, cardiovascular and respiratory mortality) in 350 urban Chinese cities. In these 5-years, the national annual average of daily maximum 8 h average (AVGDMA8) O₃ concentrations and warm-season (April–September) 4th highest daily maximum 8 h average (4DMA8) O₃ concentrations increased from 74.0 ± 15.5 μg/m³ (mean ± standard deviation) to 82.3 ± 12.0 μg/m³ and 167 ± 37.0 μg/m³ to 174 ± 30.0 μg/m³ respectively. During this period, the DMA8 O₃ concentration increased by 1.9 ± 3.3 μg/m³/yr across China, with over 70% of the monitoring sites showing a positive upward trend and 19.4% with trends >5 μg/m³/yr. The estimated long-term all-cause, cardiovascular and respiratory premature mortalities attributable to AVGDMA8 O₃ exposure in 350 Chinese cities were 181,000 (95% CI: 91,500–352,000), 112,000 (95% CI: 38,100–214,000) and 33,800 (95% CI: 0–71,400) in 2019, showing increases of 52.5%, 52.9% and 54.6% respectively compared to 2015 levels. Similarly, short-term all-cause, cardiovascular and respiratory premature mortalities attributed to ambient 4DMA8 O₃ exposure were 156,000 (95% CI: 85,300–227,000), 73,500 (95% CI: 27,500–119,000) and 28,600 (95% CI: 14,500–42,800) in 2019, increases of 19.6%, 19.8% and 21.2% respectively compared to 2015. The results of this study are important in ascertaining the effectiveness of recent emission control measures and to identify the areas that require urgent attention.
Show more [+] Less [-]Chemical aging of hydrochar improves the Cd2+ adsorption capacity from aqueous solution Full text
2021
Li, Detian | Cui, Hongbiao | Cheng, Yueqin | Xue, Lihong | Wang, Bingyu | He, Huayong | Hua, Yun | Chu, Qingnan | Feng, Yanfang | Yang, Linzhang
Hydrochar (HC) serves as a promising adsorbent to remove the cadmium from aqueous solution due to porous structure. The chemical aging method is an efficient and easy-operated approach to improve the adsorption capacity of HC. In this study, four chemical aging hydrochars (CAHCs) were obtained by using nitric acid (HNO₃) with mass fractions of 5% (N5-HC), 10% (N10-HC), and 15% (N15-HC) to age the pristine HC (N0-HC) and remove the Cd²⁺ from the aqueous solution. The results displayed that the N15-HC adsorption capacity was 19.99 mg g⁻¹ (initial Cd²⁺ concentration was 50 mg L⁻¹), which increased by 7.4 folds compared to N0-HC. After chemical aging, the specific surface area and oxygen-containing functional groups of CAHCs were increased, which contributed to combination with Cd²⁺ by physical adsorption and surface complexation. Moreover, ion exchange also occurred during the adsorption process of Cd²⁺. These findings have important implications for wastewater treatment to transform the forestry waste into a valuable adsorbent for Cd²⁺ removal from water.
Show more [+] Less [-]Phosphorus mobilization in unamended and magnesium sulfate-amended soil monoliths under simulated snowmelt flooding Full text
2021
Vitharana, Udaya W.A. | Kumaragamage, Darshani | Balasooriya, B.L.W.K. | Indraratne, Srimathie P. | Goltz, Doug
Enhanced release of phosphorus (P) from soils with snowmelt flooding poses a threat of eutrophication to waterbodies in cold climatic regions. Reductions in P losses with various soil amendments has been reported, however effectiveness of MgSO₄ has not been studied under snowmelt flooding. This study examined (a) the P release enhancement with flooding in relation to initial soil P status and (b) the effectiveness of MgSO₄ at two rates in reducing P release to floodwater under simulated snowmelt flooding. Intact soil monoliths were collected from eight agricultural fields from Southern Manitoba, Canada. Unamended and MgSO₄ surface-amended monoliths (2.5 and 5.0 Mg ha⁻¹) in triplicates were pre-incubated for 7 days, then flooded and incubated (4 °C) for 56 days. Pore water and floodwater samples collected at 7-day intervals were analyzed for dissolved reactive P (DRP), pH, Ca, Mg, Fe and Mn. Redox potential (Eh) was measured on each day of sampling. Representative soil samples collected from each field were analyzed for Olsen and Mehlich 3-P. Simulated snowmelt flooding enhanced the mobility of soil P with approximately 1.2–1.6 -fold increase in pore water DRP concentration from 0 to 21 days after flooding. Mehlich-3 P content showed a strong relationship with the pore water DRP concentrations suggesting its potential as a predictor of P loss risk during prolonged flooding. Surface application of MgSO₄ reduced the P release to pore water and floodwater. The 2.5 Mg ha⁻¹ rate was more effective than the higher rate with a 21–75% reduction in average pore water DRP, across soils. Soil monoliths amended with MgSO₄ maintained a higher Eh, and had greater pore water Ca and Mg concentrations, which may have reduced redox-induced P release and favored re-precipitation of P with Ca and Mg, thus decreasing DRP concentrations in pore water and floodwater.
Show more [+] Less [-]Role of miR164 in the growth of wheat new adventitious roots exposed to phenanthrene Full text
2021
Li, Jinfeng | Zhang, Huihui | Zhu, Jiahui | Shen, Yu | Zeng, Nengde | Liu, Shiqi | Wang, Huiqian | Wang, Jia | Zhan, Xinhua
Polycyclic aromatic hydrocarbons (PAHs), ubiquitous organic pollutants in the environment, can accumulate in humans via the food chain and then harm human health. MiRNAs (microRNAs), a kind of non-coding small RNAs with a length of 18–30 nucleotides, regulate plant growth and development and respond to environmental stress. In this study, it is demonstrated that miR164 can regulate root growth and adventitious root generation of wheat under phenanthrene exposure by targeting NAC (NAM/ATAF/CUC) transcription factor. We observed that phenanthrene treatment accelerated the senescence and death of wheat roots, and stimulated the occurrence of new roots. However, it is difficult to compensate for the loss caused by old root senescence and death, due to the slower growth of new roots under phenanthrene exposure. Phenanthrene accumulation in wheat roots caused to generate a lot of reactive oxygen species, and enhanced lipoxygenase activity and malonaldehyde concentration, meaning that lipid peroxidation is the main reason for root damage. MiR164 was up-regulated by phenanthrene, enhancing the silence of NAC1, weakening the association with auxin signal, and inhibiting the occurrence of adventitious roots. Phenanthrene also affected the expression of CDK (the coding gene of cyclin-dependent kinase) and CDC2 (a gene regulating cell division cycle), the key genes in the cell cycle of pericycle cells, thereby affecting the occurrence and growth of lateral roots. In addition, NAM (a gene regulating no apical meristem) and NAC23 may also be related to the root growth and development in wheat exposed to phenanthrene. These results provide not only theoretical basis for understanding the molecular mechanism of crop response to PAHs accumulation, but also knowledge support for improving phytoremediation of soil or water contaminated by PAHs.
Show more [+] Less [-]Reveal the metal handling and resistance of earthworm Metaphire californica with different exposure history through toxicokinetic modeling Full text
2021
Huang, Caide | Ge, Yan | Shen, Zhiqiang | Wang, Kun | Yue, Shizhong | Qiao, Yuhui
Toxicokinetic (TK) model provides a new approach to mechanistically elucidate the natural variation of metal handling strategy by adaptive and sensitive earthworm populations. Here, TK model was applied to explore the metal handling and resistance strategy of wild Metaphire californica with different historical exposure history through a 12-day re-exposure and another 12-day elimination incubation. M. californica populations showed different kinetic strategies for non-essential metals (Cd and Pb) and essential metals (Zn and Cu), which were closely related to their exposure history. M. californica from the most serious Cd-contaminated soil showed the fastest kinetic rates of both Cd uptake (K₁ = 0.78 gₛₒᵢₗ/gwₒᵣₘ/day) and elimination (K₂ = 0.23 day⁻¹), and also had the lowest Cd half-life (t₁/₂ = 3.01 day), which demonstrated the potential Cd-resistance of wild M. californica from Cd-contaminated soils. Besides, the comparative experiment showed totally different metal kinetics of laboratory Eisenia fetida from field M. californica, suggesting the impacts of distinct exposure history and species-specifical sensitivities. These findings provide a novel approach to identify and quantify resistance using TK model and also imply the risk of overlooking existing exposure background and interspecies extrapolation in eco-toxicological studies and risk assessments.
Show more [+] Less [-]Trace element contamination of soil and dust by a New Caledonian ferronickel smelter: Dispersal, enrichment, and human health risk Full text
2021
Fry, K.L. | Gillings, M.M. | Isley, C.F. | Gunkel-Grillon, P. | Taylor, Mark Patrick
Metallurgical industries remain a considerable source of trace element contamination and potential human health risk. Determination of sources is a key challenge. With respect to the South Pacific's largest and longest operating metallurgic smelter in Nouméa, New Caledonia, determining the environmental impact and subsequent human health risk associated with local ferronickel smelting is complicated by natural geological enrichment of Ni and Cr. This study applies a multi-method and multi-matrix approach to disentangle smelter emissions from geogenic sources and model the consequent health risk from industrial activity. Dust wipes (n = 108), roadside soil (n = 91), garden soil (n = 15) and household vacuum dust (n = 39) were assessed to explore geospatial trace element (As, Cr, Cu, Fe, Mn, Ni, Pb, S, V and Zn) variations across outdoor and indoor environments. Enrichment factors (EF) identified elevated levels of smelter-related trace elements: S (EF = 7), Ni (EF = 6) and Cr (EF = 4), as well as Zn (EF = 4). Smelter-related elements in soil and dust deposits were negatively correlated with distance from the facility. Similarity of Pb isotopic compositions between dust wipes, surface soil and vacuum dust indicated that potentially toxic trace elements are being tracked into homes. Non-carcinogenic health risk modelling (Hazard Index, HI) based on 15 spatial nodes across Nouméa revealed widespread exceedance of tolerable risk for children (0–2 years) for Ni (HI 1.3–15.8) and Mn (HI 0.6–1.8). Risk was greatest near the smelter and to the north-west, in the direction of prevailing wind. Given the elevated cancer risk documented in New Caledonia, disentanglement of environmental from industrial sources warrants further attention to ensure community health protection. Our analysis illustrates how the confounding effects from complex environmental factors can be distilled to improve the accuracy of point source apportionment to direct future mitigation strategies.
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