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Associations of greenness with gestational diabetes mellitus: The Guangdong Registry of Congenital Heart Disease (GRCHD) study Полный текст
2020
Qu, Yanji | Yang, Boyi | Lin, Shao | Bloom, Michael S. | Nie, Zhiqiang | Ou, Yanqiu | Mai, Jinzhuang | Wu, Yong | Gao, Xiangmin | Dong, Guanghui | Liu, Xiaoqing
Gestational diabetes mellitus (GDM) is associated with adverse short- and long-term health outcomes among mothers and their offspring. GDM affects 0.6%–15% of pregnancies worldwide and its incidence is increasing. However, intervention strategies are lacking for GDM. Previous studies indicated a protective association between greenspace and type 2 diabetes mellitus (T2DM), while few studies have explored the association between greenness and GDM. This study aimed to investigate the association between residential greenness and GDM among women from 40 clinical centers in Guangdong province, south China. The study population comprised 5237 pregnant mothers of fetuses and infants without birth defects, from 2004 to 2016. There were n = 157 diagnosed with GDM according to World Health Organization criteria. We estimated residential greenness using the Normalized Difference Vegetation Index (NDVI), derived from satellite imagery using a spatial-statistical model. Associations between greenness during pregnancy and GDM were assessed by confounder-adjusted random effects log-binomial regression models, with participating centers as the random effect. One interquartile increments of NDVI₂₅₀ₘ, NDVI₅₀₀ₘ and NDVI₁₀₀₀ₘ were associated with 13% (RR = 0.87, 95%CI: 0.87–0.87), 8% (RR = 0.92, 95%CI: 0.91–0.92) and 3% (RR = 0.97, 95%CI: 0.97–0.97) lower risks for GDM, respectively. However, NDVI₃₀₀₀ₘ was not significantly associated with GDM (RR = 0.96, 95%CI: 0.78–1.19). The risk for GDM decreased monotonically with greater NDVI. The protective effect of greenness on GDM was stronger among women with lower socioeconomic status and in environments with a lower level air pollutants. Our results suggest that greenness might provide an effective intervention to decrease GDM. Greenness and residential proximity to greenspace should be considered in community planning to improve maternal health outcomes.
Показать больше [+] Меньше [-]The toxicity of silver nanomaterials (NM 300K) is reduced when combined with N-Acetylcysteine: Hazard assessment on Enchytraeus crypticus Полный текст
2020
Mendonça, Monique C.P. | Rodrigues, Natália P. | Scott-Fordsmand, Janeck J. | Jesus, Marcelo Bispo de | Amorim, Mónica J.B.
The widespread production and use of silver nanomaterials (AgNMs) in consumer and medical products have been raising environmental concerns. Once in the environment, the soil is one of the major sinks of AgNMs due to e.g. sewage sludge applications, and invertebrates are directly exposed. In this study, we investigate the potential of N-acetylcysteine (NAC) to reduce the toxic effects of Ag NM300 K (and AgNO3) on the soil invertebrate Enchytraeus crypticus. Ag NM300 K induces mortality, reproduction impairment, and avoidance. The addition of NAC to the soil showed a remarkable reduction in the toxicity of Ag, indicating that NAC can act as a detoxifying agent for terrestrial organisms exposed to Ag materials. That the reduction in toxicity likely is caused by thiol groups, was confirmed by GSH and GSSH studies. Identifying the mechanisms and hence alternatives that allow the recovery of contaminated soils is an important mitigation measure to promote environmental safety and reduce the associated risks to human health. Further, it may inform on strategies to implement in safe-by-design industry development.
Показать больше [+] Меньше [-]Antibiotic-contaminated wastewater irrigated vegetables pose resistance selection risks to the gut microbiome Полный текст
2020
Gudda, Fredrick Owino | Waigi, Michael Gatheru | Odinga, Emmanuel Stephen | Yang, Bing | Carter, Laura | Gao, Yanzheng
Wastewater reuse in food crop irrigation has led to agroecosystem pollution concerns and human health risks. However, there is limited attention on the relationship of sub-lethal antibiotic levels in vegetables and resistance selection. Most risk assessment studies show non-significant toxicity, but overlook the link between antibiotics in crops and propagation of gut microbiome resistance selection. The review highlights the risk of antibiotics in treated water used for irrigation, uptake, and accumulation in edible vegetable parts. Moreover, it elucidates the risks to the adaptive resistance selection of the gut microbiome from sub-lethal antibiotic levels, as a result of dietary contaminated vegetables. Experiments have reported that bacterial resistance selection is possible at concentrations that are several hundred-folds lower than lethal effect levels on susceptible cells. Consequently, mutants selected at low antibiotic levels, such as those from vegetables, are fitter and more resistant compared to those selected at high concentrations. Necessary standardization, such as the development of minimum acceptable antibiotic limits allowable in food crop irrigation water, with a focus on minimum selection concentration, and not only toxicity, has been proposed. Wastewater irrigation offers environmental benefits and can contribute to food security, but it has non-addressed risks. Research gaps, future perspectives, and frameworks of mitigating the potential risks are discussed.
Показать больше [+] Меньше [-]Comparison of land use regression and random forests models on estimating noise levels in five Canadian cities Полный текст
2020
Liu, Ying | Goudreau, Sophie | Oiamo, Tor | Rainham, Daniel | Hatzopoulou, Marianne | Chen, Hong | Davies, Hugh | Tremblay, Mathieu | Johnson, James | Bockstael, Annelies | Leroux, Tony | Smargiassi, Audrey
Chronic exposure to environment noise is associated with sleep disturbance and cardiovascular diseases. Assessment of population exposed to environmental noise is limited by a lack of routine noise sampling and is critical for controlling exposure and mitigating adverse health effects. Land use regression (LUR) model is newly applied in estimating environmental exposures to noise. Machine-learning approaches offer opportunities to improve the noise estimations from LUR model. In this study, we employed random forests (RF) model to estimate environmental noise levels in five Canadian cities and compared noise estimations between RF and LUR models. A total of 729 measurements and 33 built environment-related variables were used to estimate spatial variation in environmental noise at the global (multi-city) and local (individual city) scales. Leave one out cross-validation suggested that noise estimates derived from the RF global model explained a greater proportion of variation (R2: RF = 0.58, LUR = 0.47) with lower root mean squared errors (RF = 4.44 dB(A), LUR = 4.99 dB(A)). The cross-validation also indicated the RF models had better general performance than the LUR models at the city scale. By applying the global models to estimate noise levels at the postal code level, we found noise levels were higher in Montreal and Longueuil than in other major Canadian cities.
Показать больше [+] Меньше [-]Spatial lag effect of aridity and nitrogen deposition on Scots pine (Pinus sylvestris L.) damage Полный текст
2020
Samec, Pavel | Zapletal, Miloš | Lukes, Petr | Rotter, Pavel
Scots pine (Pinus sylvestris L.) is a widespread tolerant forest tree-species; however, its adaptability to environmental change differs among sites with various buffering capacity. In this study, we compared the spatial effects of aridity index (AI) and nitrogen deposition (ND) on biomass density in natural and man-made pine stands of differing soil fertility using geographically weighted multiple lag regression. Soil fertility was defined using soil series as zonal trophic (27.9%), acidic (48.2%), gleyed (15.2%) and as azonal exposed (2.5%), maple (2.4%), ash (0.8%), wet (2.1%) and peat (0.9%) under pine stands in the Czech Republic (Central Europe; 4290.5 km²; 130–1298 m a.s.l.). Annual AI and ND in every pine stand were estimated by intersection between raster and vector from 1 × 1 km grid for years 2000, 2003, 2007 and 2010 of severe non-specific forest damage spread. Biomass density was obtained from a MODIS 250 × 250 m raster using the enhanced vegetation index (EVI) for years 2000–2015, with a decrease in EVI indicating non-specific damage. Environmental change was assessed by comparing predictor values at EVI time t and t+λ. Non-specific damage was registered over 51.9% of total forest area. Less than 8.8% of damaged stands were natural and the rest (91.2%) of damaged stands were man-made. Pure pine stands were more damaged than mixed. The ND effect prevailed up to 2007, while AI dominated later. Temporal increasing ND effect under AI effectiveness led to the most significant pine stand damage in 2008 and 2014. Predictors from 2000 to 2007 afflicted 58.5% of non-specifically damaged stands at R² 0.09–0.76 (median 0.38), but from 2000 to 2010 afflicted 57.1% of the stands at R² 0.16–0.75 (median 0.40). The most damaged stands occurred on acidic sites. Mixed forest and sustainable management on natural sites seem as effective remediation reducing damage by ND.
Показать больше [+] Меньше [-]Stimulated Raman microspectroscopy as a new method to classify microfibers from environmental samples Полный текст
2020
Laptenok, Sergey P. | Martin, Cecilia | Genchi, Luca | Duarte, Carlos M. | Liberale, Carlo
Microfibers are reported as the most abundant microparticle type in the environment. Their small size and light weight allow easy and fast distribution, but also make it challenging to determine their chemical composition. Vibrational microspectroscopy methods as infrared and spontaneous Raman microscopy have been widely used for the identification of environmental microparticles. However, only few studies report on the identification of microfibers, mainly due to difficulties caused by their small diameter. Here we present the use of Stimulated Raman Scattering (SRS) microscopy for fast and reliable classification of microfibers from environmental samples. SRS microscopy features high sensitivity and has the potential to be faster than other vibrational microspectroscopy methods. As a proof of principle, we analyzed fibers extracted from the fish gastrointestinal (GIT) tract, deep-sea and coastal sediments, surface seawater and drinking water. Challenges were faced while measuring fibers from the fish GIT, due to the acidic degradation they undergo. However, the main vibrational peaks were still recognizable and sufficient to determine the natural or synthetic origin of the fibers. Notably, our results are in accordance to other recent studies showing that the majority of the analyzed environmental fibers has a natural origin. Our findings suggest that advanced spectroscopic methods must be used for estimation of the plastic fibers concentration in the environment.
Показать больше [+] Меньше [-]Effects of microplastics exposure on ingestion, fecundity, development, and dimethylsulfide production in Tigriopus japonicus (Harpacticoida, copepod) Полный текст
2020
Yu, Juan | Tian, Ji-Yuan | Xu, Rui | Zhang, Zheng-Yu | Yang, Gui-Peng | Wang, Xue-Dan | Lai, Jing-Guang | Chen, Rong
The effects of microplastics pollution on the marine ecosystem have aroused attention. Copepod grazing stimulates dimethylsulfide (DMS) release from dimethylsulfoniopropionate (DMSP) in phytoplankton, but the effect of microplastics exposure on DMS and DMSP production during copepod feeding has not yet been revealed. Here, we investigated the effects of polyethylene (PE) and polyamide-nylon 6 (PA 6) microplastics on ecotoxicity and DMS/DMSP production in the copepod Tigriopus japonicus. The microplastics had detrimental effects on feeding, egestion, reproduction, survival, and DMS and DMSP production in T. japonicus and presented significant dose-response relationships. The 24 h-EC50 for ingestion rates (IRs) of female T. japonicus exposed to PE and PA 6 were 57.6 and 58.9 mg L⁻¹, respectively. In comparison, the body size of the copepods was not significantly affected by the microplastics during one generation of culture. Ingesting fluorescently labeled microplastics confirmed that microplastics were ingested by T. japonicus and adhered to the organs of the body surface. T. japonicus grazing promoted DMS release originating from degradation of DMSP in algal cells. Grazing-activated DMS production decreased because of reduced IR in the presence of microplastics. These results provide new insight into the biogeochemical cycle of sulfur during feeding in copepods exposed to microplastics.
Показать больше [+] Меньше [-]Laboratory simulation of microplastics weathering and its adsorption behaviors in an aqueous environment: A systematic review Полный текст
2020
Sun, Yiran | Yuan, Jianhua | Zhou, Tao | Zhao, Youcai | Yu, Fei | Ma, Jie
Microplastics (MPs) pollution has become a global environmental concern. MPs alone and in combination with pollutants can potentially cause significant harm to organisms and human beings. Weathering of MPs under various environmental stresses increases the uncertainty of their environmental fates. Compared with field surveys, laboratory simulation experiments are appropriate to simplify the research procedures and investigate the mechanisms. In this review, the effects of abrasion, solar radiation, chemical and thermal oxidation, microbial adhesion and colonization, and other environmental factors on the MPs and the relative laboratory simulation methods were summarized and discussed. Photo-oxidation and abrasion are the most appliable methods due to easy operation and adjustable weathering degree. Furthermore, the structural and components changes in weathering process and the applied characterization methods were generalized. In addition, one of important environmental behaviors, adsorption of the weathered MPs towards two typical pollutants was analyzed. Finally, three priorities for research were proposed. This paper conducts systematic summarized of the MPs weathering process and provides a reference for future studies to accurately determine the environmental risks of weathering MPs.
Показать больше [+] Меньше [-]Assessment of PM2.5-bound nitrogen-containing organic compounds (NOCs) during winter at urban sites in China and Korea Полный текст
2020
Jang, Kyoung-Soon | Choi, Mira | Park, Minhan | Park, Moon Hee | Kim, Young Hwan | Seo, Jungju | Wang, Yujue | Hu, Min | Bae, Min-Suk | Park, Kihong
In this study, ambient fine particles (PM₂.₅) were collected in two urban cities in China and Korea (Beijing and Gwangju, respectively) simultaneously in January 2018. Analysis of the nonpolar and semipolar organic matter (OM) using atmospheric pressure photoionization (APPI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) revealed that compounds containing only C, H, and O (CHO) and those containing C, H, O, and N (CHON) accounted for more than 90% of the total intensity of the OM peaks. Higher proportions of CHON compounds were observed during days with abnormally high PM₂.₅ concentrations at both sites than on regular or non-event days. The proportion of CHON species at the Beijing site was not correlated with secondary ionic species (i.e., NO₃⁻, SO₄²⁻, and NH₄⁺) or gaseous components (i.e., O₃, NO₂, and SO₂). In contrast, the proportion of CHON species at the Gwangju site was positively correlated with the concentrations of particulate nitrate and ammonium ions, assuming that ambient ammonium nitrate plays a role in the atmospheric formation of nitrogen-containing organic compounds (NOCs) at the Gwangju site and that Gwangju is more strongly influenced by secondary aerosols than Beijing is. In particular, a significant proportion of the compounds observed at the Beijing site contained only C, H and N (CHN), while negligible amounts of CHN were detected at the Gwangju site. The CHN species in Beijing were identified as quinoline compounds and the corresponding –CH₂ homologous series using complementary GC × GC-TOF MS analysis. These results suggest that NOCs and their –CH₂ homologous series from primary emissions may be significant contributors to nonpolar and semipolar OM during winter in Beijing, while NOCs with high oxidation states, likely formed via ambient-phase nitrate-mediated reactions, may be the dominant OM constituents in Gwangju.
Показать больше [+] Меньше [-]Proteomics reveals surface electrical property-dependent toxic mechanisms of silver nanoparticles in Chlorella vulgaris Полный текст
2020
Zhang, Jilai | Shen, Lin | Xiang, Qianqian | Ling, Jian | Zhou, Chuanhua | Hu, Jinming | Chen, Liqiang
Silver nanoparticles (AgNPs) are known to exert adverse effects on both humans and aquatic organisms; however, the toxic mechanisms underlying these effects remain unclear. In this study, we investigated the toxic mechanisms of various AgNPs with different surface electrical properties in the freshwater algae Chlorella vulgaris using an advanced proteomics approach with Data-Independent Acquisition. Citrate-coated AgNPs (Cit-AgNPs) and polyethyleneimine-coated AgNPs (PEI-AgNPs) were selected as representatives of negatively and positively charged nanoparticles, respectively. Our results demonstrated that the AgNPs exhibited surface electrical property-dependent effects on the proteomic profile of C. vulgaris. In particular, the negatively charged Cit-AgNPs specifically regulated mitochondrial function-related proteins, resulting in the disruption of several associated metabolic pathways, such as those related to energy metabolism, oxidative phosphorylation, and amino acid synthesis. In contrast, the positively charged PEI-AgNPs primarily targeted ribosome function-related proteins and interrupted pathways of protein synthesis and DNA genetic information transmission. In addition, Ag⁺ ions released from the AgNPs had a significant influence on protein regulation and the induction of cellular stress. Collectively, our findings provide new insight into the surface electrical property-dependent proteomic effects of AgNPs on C. vulgaris and should improve our understanding of the toxic mechanisms of AgNPs in freshwater algae.
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