The province-managing-county reform and green innovation of enterprises: evidence from the quasi-natural experiment

Environmental Science and Pollution Research - Based on the database of green patents of China’s A-share listed enterprises from 2001 to 2018, this paper identifies the impact of the...     

Impact of Covid-19 partial lockdown on PM2.5, SO2, NO2, O3, and trace elements in PM2.5 in Hanoi,Vietnam

Covid-19 lockdowns have improved the ambient air quality across the world via reduced air pollutant levels. This article aims to investigate the effect of the partial lockdown on the main ambient air pollutants and their elemental concentrations bound to PM_2.5 in Hanoi. In addition to the PM_2.5 samples collected at three urban sites in Hanoi, the daily PM_2.5, NO₂, O₃, and SO₂ levels were collected from the automatic ambient air quality monitoring station at Nguyen Van Cu street to analyze the pollution level before (March 10th–March 31st) and during the partial lockdown (April 1st–April 22nd) with “current” data obtained in 2020 and “historical” data obtained in 2014, 2016, and 2017. The results showed that NO₂, PM_2.5, O₃, and SO₂ concentrations obtained from the automatic ambient air quality monitoring station were reduced by 75.8, 55.9, 21.4, and 60.7%, respectively, compared with historical data. Besides, the concentration of PM_2.5 at sampling sites declined by 41.8% during the partial lockdown. Furthermore, there was a drastic negative relationship between the boundary layer height (BLH) and the daily mean PM_2.5 in Hanoi. The concentrations of Cd, Se, As, Sr, Ba, Cu, Mn, Pb, K, Zn, Ca, Al, and Mg during the partial lockdown were lower than those before the partial lockdown. The results of enrichment factor (EF) values and principal component analysis (PCA) concluded that trace elements in PM_2.5 before the partial lockdown were more affected by industrial activities than those during the partial lockdown.

     

Characteristics and Bioactivities of Carrageenan/Chitosan Microparticles Loading α-Mangostin

Journal of Polymers and the Environment - This study attempted to develop carrageenan/chitosan based microparticles loading α-mangostin which was extracted from Vietnamese mangosteen skin. The...     

Spatial distribution and vertical profile of polybrominated diphenyl ethers, tetrabromobisphenol A, and decabromodiphenylethane in river sediment from an industrialized region of South China

Polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBPA), and decabromodiphenylethane (DBDPE) were detected in fifteen surface sediments and two sediment cores collected from a river in one heavily industrialized region of South China. TBBPA and DBDPE were detected with concentrations ranging from 3.8 to 230 ng/g dw and from 23 to 430 ng/g dw, respectively. Σtri-hepta-BDEs and Σnona-deca-BDEs ranged from 0.7 to 7.6 ng/g dw and from 30 to 5700 ng/g dw, respectively. Σtri-hepta-BDEs showed an increasing trend whereas for Σnona-deca-BDE two sediment cores revealed a decreasing trend in more recent sediment layers which may attributed to the introduction of DBDPE. The rapid increasing trend for TBBPA and DBDPE in recent sediment layers well reflected the rising demand of these two compounds in study area.     

Effects of Two Amphibian Pathogens on the Developmental Stability of Green Frogs

Abstract: Developmental instability, measured as fluctuating asymmetry (FA), is often used as a tool to measure stress and the overall quality of organisms. Under FA, it is assumed that control of symmetry during development is costly and that under stress the trajectory of development is disturbed, resulting in asymmetric morphologies. Amphibian emergent infectious diseases (EIDs), such as Ranavirus and chytrid fungus, have been involved in several mortality events, which makes them stressors and allows for the study of FA. We analyzed nine populations of green frogs (Rana clamitans) for the presence or absence of Ranavirus and chytrid fungus. Individuals were measured to determine levels of FA in seven traits under the hypothesis that FA is more likely to be observed in individuals infected by the pathogens. Significantly higher levels of FA were found in individuals with Ranavirus compared with uninfected individuals among all populations and all traits. We did not observe FA in individuals infected with chytrid fungus for any of the traits measured. Additionally, we observed a significant association between Ranavirus infection and levels of FA in both males and females, which may indicate this viral disease is likely to affect both sexes during development. Altogether, our results indicate that some EIDs may have far‐reaching and nonlethal effects on individual development and populations harboring such diseases and that FA can be used as a conservation tool to identify populations subject to such a stress.     

沸石生物联合吸附再生工艺中溶解性有机物的特性变化

利用三维荧光技术(EEM)和凝胶过滤色谱法(GFC)研究了沸石生物联合吸附再生(ZCS)工艺中溶解性有机物(DOM)在系统中的变化规律.结果表明,生活污水DOM中主要的荧光物质有类蛋白质(荧光峰A和B)和类腐殖质(荧光峰C),经ZCS工艺处理后,荧光峰B较峰A的强度降低更多,说明类蛋白质的组成结构发生了变化;荧光峰C削...     

人工湿地中抗生素抗性大肠杆菌和抗性基因的去除与分布

抗生素的滥用导致抗生素抗性菌和抗性基因随生活污水和养殖废水的排放在环境中肆意散播,其去除及环境行为越来越受到关注。采用K-B纸片法测定了9套不同工艺构型模拟人工湿地中大肠杆菌对7种抗生素的抗性率,并应用多重PCR检测磺胺类sul1、2、3与四环素tetA、B、C、D抗性基因,探究人工湿地对抗性菌的去除效率及抗性菌、抗性基因的分布规律。结果显示,人工湿地能有效去除污水中70%左右的抗性大肠杆菌,有效降低了细菌抗性的传播风险;共计分离出535株大肠肝菌中有378株对一种以上抗生素有抗性性,以四环素、磺胺类和氨苄西林抗性率最高,达到25%以上,其他4种抗性率较低,不足20%;2种抗性基因的检出率都在70%以上;对不同采样点大肠杆菌的抗性性及抗性基因的比较发现,各部分大肠杆菌的抗性水平、多重抗性指数(MRI)以及抗性基因(sul、tet)检出率和组合数表现出:基质≥出水>进水,推测抗性菌被湿地基质截留,在基质生物膜上发生抗性基因的重组,并释放抗性菌,提高了出水中抗性水平和抗性基因检出率。     

Accumulation pattern of Dechlorane Plus and associated biological effects on rats after 90 d of exposure

Recent studies have indicated that Dechlorane Plus (DP) is widespread in the environments. However, different isomer-specific enrichment pattern of syn-DP and anti-DP was reported in biological samples from the field. In this study, Sprague–Dawley rats were consecutively exposed to commercial DP 25 by gavage for 90 d at different doses (0, 1, 10, and 100 mg kg^?1 d^?1) to investigate the accumulation pattern of syn-DP and anti-DP in liver, muscle, and serum of rats. The possible biological effects of DP on rats were also examined. Results showed that DP preferentially accumulated in the liver rather than in muscle at all exposure levels. No significant stereoselectivity of anti-DP or syn-DP in tissues was observed in the low DP exposure groups (0 and 1 mg kg^?1 d^?1) with f_anti values (defined as the concentration of the anti-DP divided by the sum of concentrations of anti- and syn-DP) ranging from 0.74 to 0.78. However, f_anti values reduced (f_anti ranged from 0.26 to 0.30) significantly in the high DP exposure groups (10 and 100 mg kg^?1 d^?1) and syn-DP was predominant in all tissues. Biochemical parameters in serum, the mRNA expression levels of certain enzymes and their activities in liver were detected. There was no observable-effect in histopathology and death during the experiment, although the mRNA expression levels of some genes in the low dosage group decreased significantly and enzyme activity of CYP 2B2 increased.     

水生和陆生生物体中卤系阻燃剂的差异性富集研究:以鲶鱼和家鸽为例

分析了水生(鲶鱼)和陆生(家鸽)生物体中卤系阻燃剂(HFRs)的组成和浓度。鲶鱼中短链氯化石蜡(SCCPs)浓度均值为30 800 ng·g~(-1)lw(脂肪归一化浓度),是最主要的HFRs,然后依次是多溴联苯醚(PBDEs)(2 300 ng·g~(-1)lw)、四溴双酚A(TBBPA)(37 ng·g~(-1)lw)、六溴环十二烷(HBCD)(21 ng·g~(-1)lw)、德克隆(DP)(14 ng·g~(-1)lw)、十溴二苯乙烷(DBDPE)(7.1 ng·g~(-1)lw)和六溴苯(HBB)(6.2 ng·g~(-1)lw);而家鸽中PBDEs含量最高(17 000 ng·g~(-1)lw),其次是SCCPs(7 600 ng·g~(-1)lw)DP(1 600 ng·g~(-1)lw)DBDPE(14 ng·g~(-1)lw)HBB、TBBPA和HBCDs(未检出)。鲶鱼和家鸽HFRs组成比较发现,鲶鱼中具有较高百分含量的低溴代PBDE单体和较低的fanti值,而家鸽中具有较高百分含量的高溴代PBDE单体和较高的fanti值。实验结果初步表明,水生生物较多地富集水溶性较大的化合物,陆生生物则较多地富集疏水性较强的化合物。研究认为以上水生和陆生生物体中污染物的差异性富集现象可能与化合物因不同物理化学性质导致的不同环境迁移行为有关。     

Site-specific bioaccumulation of polychlorinated dibenzo-<Emphasis Type="Italic">p</Emphasis>-dioxins and polychlorinated dibenzofurans (PCDD/PCDFs) in mothers and their infants living in vicinity of Bien Hoa airbase,Southern Vietnam

Bien Hoa airbase is located in Dong Nai Province (Southern Vietnam). Several sites within the airbase are highly contaminated by Agent Orange/Dioxin, and thus, they are also commonly named as an Agent Orange/Dioxin hotpot. In the present study, 36 maternal milk samples were collected from primiparas who have lived at least 5 years in four wards, Buu Long, Quang Vinh, Trung Dung and Tan Phong, which are closed to Bien Hoa airbase in order to investigate the level and distribution of Agent Orange/Dioxin exposure in different local communities. The mean concentrations of PCDD/PCDFs in four investigated wards range from 6.4 to 13.6 pgTEQ/g lipid. The highest mean TEQ of PCDD/PCDFs was observed in Buu Long ward (13.6 pgTEQ/g lipid), followed by Tan Phong ward (12.3 pgTEQ/g lipid), and the lowest value was observed in Trung Dung ward (6.4 pgTEQ/g lipid). The mean concentration of 2,3,7,8-TCDD in Buu Long (7.6 pg/g lipid) was approximately 2–6 times higher than those in Tan Phong (3.9 pg/g lipid), Quang Vinh (2.3 pg/g lipid), or Trung Dung (1.2 pg/g lipid). These results imply site-specific exposure to PCDD/PCDFs in different local communities living around Bien Hoa airbase. The mean values of daily intake of dioxin estimated for the breast fed infants living in Buu Long, Quang Vinh, Trung Dung and Tan Phong were about 80, 37.5, 31.7 and 58 pg TEQ/kg bw/day, respectively.