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Impacts of changes in environmental exposures and health behaviours due to the COVID-19 pandemic on cardiovascular and mental health: A comparison of Barcelona, Vienna, and Stockholm النص الكامل
2022
Koch, Sarah | Khomenko, Sasha | Cirach, Marta | Ubalde-Lopez, Mònica | Baclet, Sacha | Daher, Carolyn | Hidalgo, Laura | Lõhmus, Mare | Rizzuto, Debora | Rumpler, Romain | Susilo, Yusak | Venkataraman, Siddharth | Wegener, Sandra | Wellenius, Gregory A. | Woodcock, Jim | Nieuwenhuijsen, Mark
Responses to COVID-19 altered environmental exposures and health behaviours associated with non-communicable diseases. We aimed to (1) quantify changes in nitrogen dioxide (NO₂), noise, physical activity, and greenspace visits associated with COVID-19 policies in the spring of 2020 in Barcelona (Spain), Vienna (Austria), and Stockholm (Sweden), and (2) estimated the number of additional and prevented diagnoses of myocardial infarction (MI), stroke, depression, and anxiety based on these changes. We calculated differences in NO₂, noise, physical activity, and greenspace visits between pre-pandemic (baseline) and pandemic (counterfactual) levels. With two counterfactual scenarios, we distinguished between Acute Period (March 15th – April 26th, 2020) and Deconfinement Period (May 2nd – June 30th, 2020) assuming counterfactual scenarios were extended for 12 months. Relative risks for each exposure difference were estimated with exposure-risk functions. In the Acute Period, reductions in NO₂ (range of change from −16.9 μg/m³ to −1.1 μg/m³), noise (from −5 dB(A) to −2 dB(A)), physical activity (from −659 MET*min/wk to −183 MET*min/wk) and greenspace visits (from −20.2 h/m to 1.1 h/m) were largest in Barcelona and smallest in Stockholm. In the Deconfinement Period, NO₂ (from −13.9 μg/m³ to −3.1 μg/m³), noise (from −3 dB(A) to −1 dB(A)), and physical activity levels (from −524 MET*min/wk to −83 MET*min/wk) remained below pre-pandemic levels in all cities. Greatest impacts were caused by physical activity reductions. If physical activity levels in Barcelona remained at Acute Period levels, increases in annual diagnoses for MI (mean: 572 (95% CI: 224, 943)), stroke (585 (6, 1156)), depression (7903 (5202, 10,936)), and anxiety (16,677 (926, 27,002)) would be anticipated. To decrease cardiovascular and mental health impacts, reductions in NO₂ and noise from the first COVID-19 surge should be sustained, but without reducing physical activity. Focusing on cities’ connectivity that promotes active transportation and reduces motor vehicle use assists in achieving this goal.
اظهر المزيد [+] اقل [-]Coral and it's symbionts responses to the typical global marine pollutant BaP by 4D-Proteomics approach النص الكامل
2022
Pei, Yuebin | Chen, Shuai | Zhang, Yuting | Olga, Volovych | Li, Yuanchao | Diao, Xiaoping | Zhou, Hailong
The symbiosis of corals, zooxanthellae, and microbes is the foundation of the coral reef ecosystem. In addition to global warming, marine pollutants are another important factor causing the breakdown of coral symbiosis. Benzo(a)pyrene (BaP) is a globally widespread marine environmental pollutant that poses a severe threat to marine ecosystems. However, responses of coral symbionts to global marine pollutant stress remain unclear. In this study, we selected Acropora formosa as the target coral to explore its response to 50 μg L⁻¹ BaP stress using diaPASEF proteomics and 16s rRNA microbiome analysis. The results showed that: 1) the coral symbionts were sensitive to BaP stress; 2) the photosynthetic system of zooxanthellae was crucial for the balance of symbiotic relationships; 3) the destruction of the photosynthetic system induced a zooxanthellae hypoxic stress response; 4) corals adapted to BaP stress by promoting non-essential protein degradation and changing energy metabolism strategies; 5) symbiotic bacteria showed strong adaptability to BaP. This study not only fills the gap in understanding the response mechanism of coral symbionts under BaP stress, but also provides fundamental data for coral reef protection strategies.
اظهر المزيد [+] اقل [-]Source attribution and quantification of atmospheric nickel concentrations in an industrial area in the United Kingdom (UK) النص الكامل
2022
Font, Anna | Tremper, Anja H. | Priestman, Max | Kelly, Frank J. | Canonaco, Francesco | Prévôt, André S.H. | Green, David C.
Pontardawe in South Wales, United Kingdom (UK), consistently has the highest concentrations of nickel (Ni) in PM₁₀ in the UK and repeatedly breaches the 20 ng m⁻³ annual mean EU target value. Several local industries use Ni in their processes. To assist policy makers and regulators in quantifying the relative Ni contributions of these industries and developing appropriate emission reduction approaches, the hourly concentrations of 23 elements were measured using X-ray fluorescence alongside meteorological variables and black carbon during a four-week campaign in November–December 2015. Concentrations of Ni ranged between 0 and 2480 ng m⁻³ as hourly means. Positive Matrix Factorization (PMF) was used to identify sources contributing to measured elements. Cluster analysis of bivariate polar plots of those factors containing Ni in their profile was further used to quantify the industrial processes contributing to ambient PM₁₀ concentrations. Two sources were identified to contribute to Ni concentrations, stainless-steel (which contributed to 10% of the Ni burden) and the Ni refinery (contributing 90%). From the stainless-steel process, melting activities were responsible for 66% of the stainless-steel factor contribution.
اظهر المزيد [+] اقل [-]Association of exposure to organophosphate esters with increased blood pressure in children and adolescents النص الكامل
2022
Hu, Liqin | Yu, Meng | Li, Yaping | Liu, Ling | Li, Xiang | Song, Lulu | Wang, Youjie | Mei, Surong
Organophosphate esters (OPEs) are widely added to various industrial and consumer products, and are mainly used as flame retardants and plasticizers. Existing epidemiological studies suggest that OPE exposure may be linked to increased blood pressure (BP) and hypertension risk in adults. However, it remains unclear whether OPE exposure is associated with increased BP in children and adolescents. Here, we investigated the associations between OPE exposure and BP levels in 6–18-year-old children and adolescents from a cross-sectional study in Liuzhou, China. OPE metabolites were determined in spot urine samples (n = 1194) collected between April and May 2018. Three measurements of systolic and diastolic BP for each participant were averaged as study outcomes. Associations of OPE exposure with age-, sex- and height-standardized BP were assessed using linear regression models. We found that each natural log unit increment of bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) was associated with a 0.06 standard deviation unit (95% confidant interval (CI): 0.01, 0.11) increase in systolic BP z-score. When conducting stratified analysis based on sex, age, and BMI category, BDCIPP was shown to be positively associated with systolic/diastolic BP z-score in females, but not in males. The associations between bis(2-butoxyethyl) phosphate (BBOEP) and systolic/diastolic BP z-score were pronounced in adolescents, but not in children. Moreover, a significant positive association between 1-hydroxy-2-propyl bis(1-chloro-2-propyl) phosphate (BCIPHIPP) and diastolic BP z-score was observed in obese subjects. The present study provides the first evidence that OPE exposure was related to increased BP in children and adolescents. Given the scarcity of high-quality evidence supporting these results, the health effects of OPEs are warrant investigation in well-designed prospective studies.
اظهر المزيد [+] اقل [-]Toxicokinetics and toxicodynamics of plastic and metallic nanoparticles: A comparative study in shrimp النص الكامل
2022
Zhu, Xiaopeng | Teng, Jia | Xu, Elvis Genbo | Zhao, Jianmin | Shan, Encui | Sun, Chaofan | Wang, Qing
Nanoplastic is recognized as an emerging environmental pollutant due to the anticipated ubiquitous distribution, increasing concentration in the ocean, and potential adverse health effects. While our understanding of the ecological impacts of nanoplastics is still limited, we benefit from relatively rich toxicological studies on other nanoparticles such as nano metal oxides. However, the similarity and difference in the toxicokinetic and toxicodynamic aspects of plastic and metallic nanoparticles remain largely unknown. In this study, juvenile Pacific white shrimp Litopenaeus vannamei was exposed to two types of nanoparticles at environmentally relative low and high concentrations, i.e., 100 nm polystyrene nanoplastics (nano-PS) and titanium dioxide nanoparticles (nano-TiO₂) via dietary exposure for 28 days. The systematic toxicological evaluation aimed to quantitatively compare the accumulation, excretion, and toxic effects of nano-PS and nano-TiO₂. Our results demonstrated that both nanoparticles were ingested by L. vannamei with lower egestion of nano-TiO₂ than nano-PS. Both nanoparticles inhibited the growth of shrimps, damaged tissue structures of the intestine and hepatopancreas, disrupted expression of immune-related genes, and induced intestinal microbiota dysbiosis. Nano-PS exposure caused proliferative cells in the intestinal tissue, and the disturbance to the intestinal microbes was also more serious than that of nano-TiO₂. The results indicated that the effect of nano-PS on the intestinal tissue of L. vannamei was more severe than that of nano-TiO₂ with the same particle size. The study provides new theoretical basis of the similarity and differences of their toxicity, and highlights the current lack of knowledge on various aspects of absorption, distribution, metabolism, and excretion (ADME) pathways of nanoplastics.
اظهر المزيد [+] اقل [-]Significance of chemical affinity on metal subcellular distribution in yellow perch (Perca flavescens) livers from Lake Saint-Pierre (QUEBEC, Canada) النص الكامل
2022
Desjardins, Kimberley | Khadra, Mélissa | Caron, Antoine | Ponton, Dominic E. | Rosabal, Maikel | Amyot, Marc
The subcellular partitioning approach provides useful information on the location of metals within cells and is often used on organisms with high levels of bioaccumulation to establish relationships between the internal concentration and the potential toxicity of metals. Relatively little is known about the subcellular partitioning of metals in wild fish with low bioaccumulation levels in comparison with those from higher contaminated areas. This study aims to examine the subcellular partitioning of various metals considering their chemical affinity and essentiality at relatively low contamination levels. Class A (Y, Sr), class B (Cu, Cd, MeHg), and borderline (Fe, Mn) metal concentrations were measured in livers and subcellular fractions of yellow perch (n = 21) collected in Lake Saint-Pierre, QC, Canada. The results showed that all metals, apart from MeHg, were distributed among subcellular fractions according to their chemical affinity. More than 60% of Y, Sr, Fe, and Mn were found in the metal-sensitive fractions. Cd and Cu were largely associated with the metallothionein-like proteins and peptides (60% and 67% respectively) whereas MeHg was found mainly in the metal-sensitive fractions (86%). In addition, the difference between the subcellular distribution of Cu and other essential metals like Fe and Mn denotes that, although the essentiality of some metals is a determinant of their subcellular distribution, the chemical affinity of metals is also a key driver. The similarity of the subcellular partitioning results with previous studies on yellow perch and other fish species from higher contaminated areas supports the idea that metals are distributed in the cellular environment according to their chemical properties regardless of the bioaccumulation gradient.
اظهر المزيد [+] اقل [-]Heavy metal ATPase genes (HMAs) expression induced by endophytic bacteria, “AI001, and AI002” mediate cadmium translocation and phytoremediation النص الكامل
2022
Ullah, Ihsan | Mateen, Aisha | Ahmad, Mian Afaq | Munir, Iqbal | Iqbal, Aqib | Alghamdi, Khalid M.S. | Al-Solami, Habeeb M. | Siddiqui, Muhammad Faisal
Contamination of heavy metals is a serious threat, which causes threats to the environment. Our study aimed to determine the role of endophytic bacteria in Cd phytoremediation and heavy metal ATPase gene expression. Cadmium (Cd) resistant endophytic bacteria were isolated from Solanum nigrum on LB agar plates, contaminated with 0–30 mg/L Cd. The phosphate solubilization and indole-3-acetic acid (IAA) production of endophytes were estimated by growing them on Pikovskaya agar medium and GC-MS analysis, respectively. An experiment in a pot was performed to evaluate the effects of bacteria on rice plants contaminated with 5–25 mg/L of Cd. Expression of Cd response genes was quantified through qRT–PCR and Cd translocation from one part to another part of the plant was measured through the ICP. BLAST alignment of 16 S-rDNA gene sequences confirmed the bacterial isolates as Serratia sp. AI001 and Klebsiella sp. Strain AI002. Both strains tolerated Cd up to 25 mg/L and produced 27–30 μg/mL of IAA. Inoculation of AI001 and AI002 improved plant growth dynamics (i.e., plant length, biomass, chlorophyll contents), relieved electrolyte leakage, and improved reduced glutathione significantly (P < 0.05). The inoculation of AI001 and AI002 significantly (P < 0.05) induced the expression of heavy metal ATPase genes ie., “HMA2, HMA3, and HMA4” and Cd translocation compared to uninoculated plants. Both AI001 and AI002 exhibited very prominent plant-growth-promoting and Cd phytoremediation properties. The results revealed that isolates also contributed a lot to the expression of rice plant heavy metal ATPase genes and in the Cd translocation in the plant.
اظهر المزيد [+] اقل [-]A multivariate Chain-Bernoulli-based prediction model for cyanobacteria algal blooms at multiple stations in South Korea النص الكامل
2022
Kim, Kue Bum | Uranchimeg, Sumiya | Kwon, Hyun-Han
Predicting the occurrence of algal blooms is of great importance in managing water quality. Moreover, the demand for predictive models, which are essential tools for understanding the drivers of algal blooms, is increasing with global warming. However, modeling cyanobacteria dynamics is a challenging task. We developed a multivariate Chain-Bernoulli-based prediction model to effectively forecast the monthly sequences of algal blooms considering hydro-environmental predictors (water temperature, total phosphorus, total nitrogen, and water velocity) at a network of stations. The proposed model effectively predicts the risk of harmful algal blooms, according to performance measures based on categorical metrics of a contingency table. More specifically, the model performance assessed by the LOO cross-validation and the skill score for the POD and CSI during the calibration period was over 0.8; FAR and MR were less than 0.15. We also explore the relationship between hydro-environmental predictors and algal blooms (based on cyanobacteria cell count) to understand the dynamics of algal blooms and the relative contribution of each potential predictor. A support vector machine is applied to delineate a plane separating the presence and absence of algal bloom occurrences determined by stochastic simulations using different combinations of predictors. The multivariate Chain-Bernoulli-based prediction model proposed here offers effective, scenario-based, and strategic options and remedies (e.g., controlling the governing environmental predictors) to relieve or reduce increases in cyanobacteria concentration and enable the development of water quality management and planning in river systems.
اظهر المزيد [+] اقل [-]Synthesis of a robust, water-stable, and biodegradable pulp foam by poly-lactic acid coating towards a zero-plastic earth النص الكامل
2022
Zhang, Yuxiang | Liao, Jianming | Li, Jun | Guo, Shasha | Mo, Lihuan | Liu, Zhan | Xiong, Qingang
Biodegradable cellulosic pulp foams with robustness and water resistance are urgently needed in nowadays to replace petroleum-based plastic foams for environmental sustainability. In this work, a facile protocol to fabricate robust poly-lactic acid (PLA) coated cellulose foams (PCCF) was developed through a combined water-based foaming and PLA melt-coating process using pulp as the raw material. In the synthesis, the so-called PLA coating was realized through melting PLA powders dispersed between fibers by an in-situ heating and post cooling process. Performance tests revealed that the incorporation of PLA coating significantly enhances mechanical strength, water stability, and biodegradability of the synthesized PCCF samples compared with conventional cellulosic foams. Specifically, the low-density PCCF were observed with mechanical strength up to 81.24 kPa, high water stability, and more than 95% degradation in 56 days. As the fabrication process is simple and pulp is highly cost competitive, our proposed synthesis strategy makes the PCCF a promising substitute for petroleum-based plastic foams at large-scale production.
اظهر المزيد [+] اقل [-]Impact of resuspended mine tailings on benthic biodiversity and ecosystem processes: The case study of Portmán Bay, Western Mediterranean Sea, Spain النص الكامل
2022
Gambi, Cristina | Canals, M. (Miquel) | Corinaldesi, Cinzia | Dell’Anno, Antonio | Manea, Elisabetta | Pusceddu, Antonio | Sanchez-Vidal, Anna | Danovaro, Roberto
Industrial seabed mining is expected to cause significant impacts on marine ecosystems, including physical disturbance and the generation of plumes of toxin-laden water. Portmán Bay (NW Mediterranean Sea), where an estimated amount of 60 Mt of mine tailings from sulphide ores were dumped from 1957 to 1990, is one of the most metal-polluted marine areas in Europe and worldwide. This bay can be used to assess the impact on marine ecosystems of particle settling from sediment plumes resulting from mine tailings resuspension. With this purpose in mind, we conducted a field experiment there to investigate subsequent effects of deposition of (artificially resuspended) contaminated sediments on (i) prokaryotic abundance and meiofaunal assemblages (in terms of abundance and diversity), (ii) the availability of trophic resources (in terms of organic matter biochemical composition), and (iii) a set of ecosystem functions including meiofaunal biomass, heterotrophic C production and C degradation rates. The results of this study show that mine tailings resuspension and plume deposition led to the decline of prokaryotic abundance and nematode's biodiversity. The later decreased because of species removal and transfer along with particle resuspension and plume deposition. Such changes were also associated to a decrease of the proteins content in the sediment organic matter, faster C degradation rates and higher prokaryotic C production. Overall, this study highlights that mine tailing resuspension and ensuing particle deposition can have deleterious effects on both prokaryotes and nematode diversity, alter biogeochemical cycles and accelerate C degradation rates. These results should be considered for the assessment of the potential effects of seabed mineral exploitation on marine ecosystems at large.
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