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Polystyrene particles combined with di-butyl phthalate cause significant decrease in photosynthesis and red lettuce quality 全文
2021
Dong, Youming | Song, Zhengguo | Liu, Yu | Gao, Minling
Microplastics, an emerging pollutant in the environment, have attracted extensive attention in recent years for their possible negative impact on organisms. However, direct and indirect effects of polystyrene (PS) microplastics on vegetables are still not completely known. In this study, we used red lettuce (Lactuca sativa L. Red Sails) in a hydroponic system to investigate the effects of nano- and micro-sized PS and dibutyl phthalate (DBP) on the photosynthesis and red lettuce quality. The results clearly indicated that PS reduced the bioavailability of DBP while causing a decrease in the photosynthetic parameters as well as the total chorophyll content compared to DBP alone by affecting the crystalline structure of the water-soluble chlorophyll protein. Compared with DBP monotherapy, the presence of PS significantly increased hydrogen peroxide and malondialdehyde content in the lettuce treated with DBP, indicating serious oxidative damage. Furthermore, the soluble protein and sugar content in lettuce leaves decreased with higher PS concentration and smaller PS size. It may be due to PS inhibited lettuce root and ribulose-1,5-bisphosphate carboxylase/oxygenase activities. In contrast, nitrite content increased significantly with the induction of the glutathione-ascorbic acid cycle, indicating that the presence of PS reduced the quality of DBP-treated-red lettuce. Additionally, the nano-sized PS greatly inhibited lettuce growth and quality more than the micro-sized PS. This study described the interactions between microplastics and phthalates using molecular simulation and experimental validation to highlight the potential risks of microplastics on vegetable crop production.
显示更多 [+] 显示较少 [-]Mediated relationships between multiple metals exposure and fasting blood glucose by reproductive hormones in Chinese men 全文
2021
Zan, Gaohui | Li, Longman | Cheng, Hong | Huang, Lulu | Huang, Sifang | Luo, Xiaoyu | Xiao, Lili | Liu, Chaoqun | Zhang, Haiying | Mo, Zengnan | Yang, Xiaobo
Previous studies have reported metals exposure contribute to the change of fasting blood glucose (FBG) level. However, the roles of reproductive hormones in their associations have not been fully elucidated. The aim of the study is to investigate the associations of multiple serum metals with reproductive hormones, and to further explore potential roles of reproductive hormones in relationships between metals exposure and FBG level. A total of 1911 Chinese Han men were analyzed by a cross-sectional study. We measured serum levels of 22 metals by inductively coupled plasma mass spectrometer (ICP-MS). FBG, total testosterone (TT), estradiol (E2), follicle stimulating hormone (FSH), and sex hormone-binding globulin (SHBG) levels were determined. Least absolute shrinkage and selection operator (LASSO) regression models were conducted to select important metals, and restricted cubic spline models were then used to estimate dose-response relationships between selected metals and reproductive hormones. We also conducted mediation analyses to evaluate whether reproductive hormones played mediating roles in the associations between metals and FBG. We found significant inverse dose-dependent trends of copper, tin and zinc with E2; zinc with SHBG; copper and nickel with TT, while significant positive dose-dependent trend of iron with E2, respectively. Moreover, approximately inverted U-shaped associations existed between lead and SHBG, iron and TT. In addition, E2, SHBG and TT were negatively associated with FBG level. In mediation analyses, the association of copper with FBG was mediated by E2 and TT, with a mediation ratio of 10.4% and 22.1%, respectively. Furthermore, E2 and SHBG mediated the relationship of zinc with FBG, with a mediation ratio of 7.8% and 14.5%, respectively. E2 mediated 11.5% of positive relationship between tin with FBG. Our study suggested that the associations of metals exposure with FBG may be mediated by reproductive hormones.
显示更多 [+] 显示较少 [-]Current trends and possibilities for exploitation of Grape pomace as a potential source for value addition 全文
2021
Chowdhary, Pankaj | Gupta, Abhishek | Gnansounou, Edgard | Pandey, Ashok | Chaturvedi, Preeti
Grape pomace (GP) is a low-value by-product that contains a significant amount of high value-added products. The huge amount of non-edible residues of GP wastes (seeds, skins, leaves and, stems) produced by wine industries causes’ environmental pollution, management issues as well as economic loss. Studies over the past 15–20 years revealed that GP could serve as a potential source for valuable bioactive compounds like antioxidants, bioactive, nutraceuticals, single-cell protein, and volatile organic compounds with an increasing scientific interest in their beneficial effects on human and animal health. However, the selection of appropriate techniques for the extraction of these compounds without compromising the stability of the extracted products is still a challenging task for the researcher. Based on the current scenario, the review mainly summarizes the novel applications of winery wastes in many sectors such as agriculture, pharmaceuticals, cosmetics, livestock fields, and also the bio-energy recovery system. We also summarize the existing information/knowledge on several green technologies for the recovery of value-added by-products. For the promotion of many emerging technologies, the entrepreneur should be aware of the opportunities/techniques for the development of high-quality value-added products. Thus, this review presents systematic information on value-added by-products that are used for societal benefits concerning the potential for human health and a sustainable environment.
显示更多 [+] 显示较少 [-]Emerging organic compounds in European groundwater 全文
2021
Bunting, S.Y. | Lapworth, D.J. | Crane, E.J. | Grima-Olmedo, J. | Koroša, A. | Kuczyńska, A. | Mali, N. | Rosenqvist, L. | van Vliet, M.E. | Togola, A. | López, B.
In Europe, emerging organic compounds (EOCs) in groundwater is a growing research area. Prioritisation for monitoring EOCs in Europe was formalised in 2019 through the development of the first voluntary groundwater watch list (GWWL). Despite this, groundwater occurrence data in the peer reviewed literature for Europe has not been reviewed to date. Questions surrounding the effect, toxicity, movement in the subsurface and unsaturated zone make the process of regulating EOC use difficult. The aim in Europe is to develop a unified strategy for the classification, and prioritisation of EOCs to be monitored in groundwater. This paper compiles evidence from the recent published studies from across Europe, since 2012, when the last major literature global review of EOCs in groundwater took place. A total of 39 studies were identified for review based on specific selection criteria (geography, publication date, sample size>10, inclusion of EOCs data). Data on specific compounds, and associated meta-data, are compiled and reviewed. The two most frequently detected EOCs, carbamazepine and caffeine, occurred in groundwater at concentrations of up to 2.3 and 14.8 μg/L, respectively.The most frequently reported category of compounds were ‘Pharmaceuticals’; a highly studied group with 135 compounds identified within 31 of the 39 studies. In Europe, the majority of reviewed studies (23) were at a regional scale, looking specifically at EOCs in a specific city or aquifer. The use of analytical methods is not uniform across Europe, and this inevitably influences the current assessment of EOCs in groundwater. A correlation between the number of compounds analysed for, and the number detected in groundwater highlights the need for further studies, especially larger-scale studies throughout Europe. For the development of EU and national regulation, further work is required to understand the occurrence and impacts of EOCs in groundwater throughout Europe and elsewhere.
显示更多 [+] 显示较少 [-]Environmental concentrations of antifouling paint particles are toxic to sediment-dwelling invertebrates 全文
2021
Muller-Karanassos, Christina | Arundel, William | Lindeque, Penelope K. | Vance, Thomas | Turner, Andrew | Cole, Matthew
Antifouling paint particles (APPs) and associated metals have been identified in sediments around boatyards and marinas globally, but the effects of APPs on benthic organisms are largely unknown. Sub-lethal endpoints were measured following laboratory exposures of the harbour ragworm (Hediste diversicolor) and the common cockle (Cerastoderma edule) to environmentally relevant concentrations of biocidal (‘modern’ and ‘historic’) and biocide-free (‘silicone’) APPs added to clean estuarine sediment. Further, the 5-day median lethal concentrations (LC₅₀) and effects concentrations (EC₅₀) for modern biocidal APPs were calculated. For ragworms, significant decreases in weight (15.7%; p < 0.01) and feeding rate (10.2%; p < 0.05) were observed in the modern biocidal treatment; burrowing behaviour was also reduced by 29% in this treatment, but was not significant. For cockles, the modern biocidal treatment led to 100% mortality of all replicates before endpoints were measured. In cockles, there was elevated levels of metallothionein-like protein (MTLP) in response to both modern and historic biocidal treatments. Ragworms had a higher tolerance to modern APPs (5-day LC₅₀:19.9 APP g L⁻¹; EC₅₀: 14.6 g L⁻¹) compared to cockles (5-day LC₅₀: 2.3 g L⁻¹ and EC₅₀: 1.4 g L⁻¹). The results of this study indicate that modern biocidal APPs, containing high Cu concentrations, have the potential to adversely affect the health of benthic organisms at environmentally relevant concentrations. The findings highlight the need for stricter regulations on the disposal of APP waste originating from boatyards, marinas and abandoned boats.
显示更多 [+] 显示较少 [-]Long-term effects of atmospheric deposition on British plant species richness 全文
2021
Tipping, Edward | Davies, Jessica A.C. | Henrys, Peter A. | Jarvis, Susan G. | Smart, S. M. (Simon M.)
The effects of atmospheric pollution on plant species richness (nₛₚ) are of widespread concern. We carried out a modelling exercise to estimate how nₛₚ in British semi-natural ecosystems responded to atmospheric deposition of nitrogen (Ndₑₚ) and sulphur (Sdₑₚ) between 1800 and 2010. We derived a simple four-parameter equation relating nₛₚ to measured soil pH, and to net primary productivity (NPP), calculated with the N14CP ecosystem model. Parameters were estimated from a large data set (n = 1156) of species richness in four vegetation classes, unimproved grassland, dwarf shrub heath, peatland, and broadleaved woodland, obtained in 2007. The equation performed reasonably well in comparisons with independent observations of nₛₚ. We used the equation, in combination with modelled estimates of NPP (from N14CP) and soil pH (from the CHUM-AM hydrochemical model), to calculate changes in average nₛₚ over time at seven sites across Britain, assuming that variations in nₛₚ were due only to variations in atmospheric deposition. At two of the sites, two vegetation classes were present, making a total of nine site/vegetation combinations. In four cases, nₛₚ was affected about equally by pH and NPP, while in another four the effect of pH was dominant. The ninth site, a chalk grassland, was affected only by NPP, since soil pH was assumed constant. Our analysis suggests that the combination of increased NPP, due to fertilization by Ndₑₚ, and decreased soil pH, primarily due to Sdₑₚ, caused an average species loss of 39% (range 23–100%) between 1800 and the late 20th Century. The modelling suggests that in recent years nₛₚ has begun to increase, almost entirely due to reductions in Sdₑₚ and consequent increases in soil pH, but there are also indications of recent slight recovery from the eutrophying effects of Ndₑₚ.
显示更多 [+] 显示较少 [-]Silica nanoparticles inhibiting the differentiation of round spermatid and chromatin remodeling of haploid period via MIWI in mice 全文
2021
Liu, Jianhui | Li, Xiangyang | Zhou, Guiqing | Zhang, Yue | Sang, Yujian | Wang, Ji | Li, Yanbo | Ge, Wei | Sun, Zhiwei | Zhou, Xianqing
Researches have shown that silica nanoparticles (SiNPs) could reduce both the quantity and quality of sperm. However, the mechanism of toxicity induced by SiNPs in the male reproductive system is still unclear. In this study, male mice were randomly divided into a control group, and SiNPs treated group (20 mg/kg dose; n = 30 per group). Half of the mice per group were sacrificed on 35 days and the remaining on 50 days of the SiNPs exposure. SiNPs were found to decrease sperm count and mobility, increase the sperm abnormality rate, and damage the testes' structure. Furthermore, SiNPs decreased the protein levels of Protamine 1(PRM1) and elevated the histones' levels and suppressed the chromatin condensation of sperm. There was a significant reduction of the ubiquitinated H2A (ubH2A)/H2B (ubH2B) and RING finger protein 8 (RNF8) levels in the spermatid nucleus, while the RNF8 level in the spermatid cytoplasm increased evidently. The protein expression levels of PIWI-like protein 1(MIWI) in the late spermatids significantly increased on day 35 of SiNPs exposure. After 15 days of the withdrawal, the sperm parameters and protamine levels, and histones in the epididymal sperm were unrecovered; however, the changes in testis induced by SiNPs were recovered. Our results suggested that SiNPs could decrease the RNF8 level in the nucleus of spermatid either by upregulating of the expression of MIWI or by inhibiting its degradation. This resulted in the detention of RNF8 in the cytoplasm that maybe inhibited the RNF8-mediated ubiquitination of ubH2A and ubH2B. These events culminated in creating obstacles during the H2A and H2B removal and chromatin condensation, thereby suppressing the differentiation of round spermatids and chromatin remodeling, which compromised the sperm quality and quantity.
显示更多 [+] 显示较少 [-]Temporal variation characteristics and source apportionment of metal elements in PM2.5 in urban Beijing during 2018–2019 全文
2021
Zhao, Shuang | Tian, Hezhong | Luo, Lining | Liu, Huanjia | Wu, Bobo | Liu, Shuhan | Bai, Xiaoxuan | Liu, Wei | Liu, Xiangyang | Wu, Yiming | Lin, Shumin | Guo, Zhihui | Lv, Yunqian | Xue, Yifeng
To explore high-resolution temporal variation characteristics of atmospheric metal elements concentration and more accurate pollution sources apportionment, online monitoring of metal elements in PM₂.₅ with 1-h time resolution was conducted in Beijing from August 22, 2018 to August 21, 2019. Concentration of 18 elements varied between detection limit (ranging from 0.1 to 100 ng/m³) and nearly 25 μg/m³. Si, Fe, Ca, K and Al represented major elements and accounted for 93.47% of total concentration during the study period. Compared with previous studies, airborne metal pollution in Beijing has improved significantly which thanks to strict comprehensive control measures under the Clean Air Action Plan since 2013. Almost all elements present higher concentrations on weekdays than weekends, while concentrations of elements associated with dust sources during holidays are higher than those in working days after the morning peak, and there is almost no concentration difference in the evening peak period. Soil and dust, vehicle non-exhaust emissions, biomass, industrial processes and fuel combustion were apportioned as main sources of atmospheric metal pollution, accounting for 63.6%, 18.4%, 16.8%, 1.0% and 0.18%, respectively. Furthermore, main occurrence season of metal pollution is judged by characteristic radar chart of varied metal elements proposed for the first time in this study, for example, fuel combustion type pollution mainly occurs in winter and spring. Results of 72-h backward trajectory analysis of air masses showed that, except for local emissions, atmospheric metal pollution in Beijing is also affected by regional transport from Inner Mongolia, Hebei, the Bohai Sea and Heilongjiang.
显示更多 [+] 显示较少 [-]Hollow porous molecularly imprinted polymers as emerging adsorbents 全文
2021
Bhogal, Shikha | Kuldip Kaur, | Mohiuddin, Irshad | Kumar, Sandeep | Lee, Jechan | Brown, Richard J.C. | Kim, Ki Hyun | Malik, Ashok Kumar
Hollow porous molecularly imprinted polymers (HPMIPs) are identified as promising adsorbents with many advantageous properties (e.g., large number of imprinted cavities, highly accessible binding sites, controllable pore structure, and fast mass transfer). Because of such properties, HPMIPs can exhibit improved binding capacity and kinetics to make analyte molecules readily interact with a greater number of recognition sites on the imprinted shell. This review highlights the synthesis and utility of HPMIPs as adsorbents to cover diverse targets of interest (e.g., endocrine disrupting chemicals, pharmaceuticals, pesticides, and heavy metal ions). The overall potential of HPMIPs is thus discussed in the context of analytical chemistry with particular focus on the efficient extraction of trace-level targets from complex matrices.
显示更多 [+] 显示较少 [-]Sensitivity and specificity of macroinvertebrate responses to gradients of multiple agricultural stressors 全文
2021
Brooks, Andrew J. | Bray, Jonathan | Nichols, Susan J. | Shenton, Mark | Kaserzon, Sarit | Nally, Ralph Mac | Kefford, Ben J.
Environmental degradation of rivers in agricultural landscapes is typically caused by multiple co-occurring stressors, but how interactions among stressors affect freshwater ecosystems is poorly understood. Therefore, we investigated the sensitivity and specificity of several measures of benthic macroinvertebrate community response to the individual and combined effects of the pesticide sulfoxaflor (SFX), increased sand sedimentation and elevated nutrients using outdoor recirculating mesocosms. Among the single stressor treatments, nutrients had no observable impact and sand only affected one community response measure compared to controls. High SFX levels had the largest effects on benthic macroinvertebrate communities, negatively affecting six of seven macroinvertebrate response measures. Sulfoxaflor had similar adverse effects on biota when in combination with sand and nutrients in the multi-stressor treatment, suggesting that generally SFX has overwhelming and pervasive effects irrespective of the presence of the other stressors. In contrast to SFX, elevated nutrients had no detectable effect on macroinvertebrate communities, likely as a consequence of nutrients being rapidly taken up by bacteria rather than by benthic algae. Elevated sand sedimentation increased the negative effects of SFX on sediment sensitive taxa, but generally had limited biological effects. This was despite the levels of sedimentation in our treatments being at concentrations that have caused large impacts in other studies. This research points to direct and rapid toxic effects of SFX on stream macroinvertebrates, contrasting with effects of the other stressors. This study emphasises that pesticide effects could be misattributed to other common freshwater stressors, potentially focussing restoration actions on a stressor of lesser importance.
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