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The aquatic environment, linked to the sustainable development of human existence and ecological environment, is influenced comprehensively by anthropogenic and natural activities. In light of the continuously low concentration of dissolved oxygen (DO) in surface water in plain river networks and the phenomenon of delay in the improvement of surface water quality, this research aims to introduce a method that may be utilized in identifying the critical driving forces of DO in surface water and their lagging characteristics, which will contribute to the assessment and adjustment of water quality drivers and/or policies. The research analyzes a typical small watershed in a river network region of the Yangtze River Delta plain as the study area, collecting 35-year (1986-2020) data on several water quality parameters, decades of anthropogenic activities, and two natural factors. The time series methods of vector autoregressive model, Granger causality tests, forecast error variance decompositions, and impulse response functions (hereinafter referred to as VAR+), which are rarely applied in related research, were employed in this study and proved helpful for screening out pivotal drivers and capturing the lagging responses of DO level to driving forces at each lagged time. Results show that there exists a fluctuating drop in DO level in surface water from 1986 to 2008 and a steady climb from 2008 to 2020, with the lowest DO level being present in 2008. The impulsive perturbations of phosphate fertilizer consumption (PFC), motor vessel number, and precipitation minimally increase DO concentration, while the impulsive perturbation of gross domestic product (GDP) causes the sharpest drop in DO level. With these perturbations, the driving force of PFC persists for approximately seven years, and the driving forces of water temperature, permanent population, and GDP persist for only five years. Future research could be conducted with spatial hysteresis, selection of lag order and variable quantity within the model, as well as intermediate variables between drivers and DO level for exploring driving pathways and mechanisms.

Solid waste, that is produced as a result of human activity on a daily basis, must be properly managed. Like other cities in developing nations, Addis Ababa is facing problems linked to poorly managing solid waste gathering operations. This study analyzed the existing public solid waste gathering system in the city and undertook a comparative analysis with Shanghai’s solid waste collection system. Qualitative and quantitative data were collected th- rough surveys as well as secondary sources and then comparative analysis with Shanghai has been undertaken. According to the investigation of this research, solid waste collection coverage of Addis Ababa is 70% and only 28.6% of households have separate solid waste at source. Besides, according to respondents, 75.3% of residents were using a sack to collect the waste and only 14.5% were using the waste bin. The study found that lack of access of infrastructures, a lack of an adequately built collection route system and schedule, inadequate and faulty facilities for operations, and corner littering around skips that resulted in improper disposal are among the causes of poor efficiency of solid waste handling in the metropolitan. Lack of understanding, improper disposal, the poor status of waste collectors, the absence of the private sector, and public engagement are some of the social issues that have been experienced. The main problem with the incompetence of this sector in the city was the lack of trained labor and inadequate service delivery. In conclusion, based on Shanghai City’s best practices, the research applied about useful suggestions for strengthening the system and re-designing it.

Characterizing the occurrence of organic contaminants (OCs) of environmental health concern in municipal sewage sludges is essential for safe handling and disposal of these abundant materials. This meta-analysis aimed to (i) summarize the extent of studies performed on the chemical composition of sewage sludges from China and the U.S., the world’s two largest chemical producers, (ii) identify chemical groups of priority concern, (iii) quantitatively compare chemical abundance in sludge between nations, (iv) determine longitudinal contaminant accumulation trends in sludge, and (v) identify data gaps with regard to OC concentrations in sludge. A literature search was conducted on concentrations of OCs in U.S. sludges produced during treatment of domestic and industrial wastewater and compared statistically to contaminant levels in Chinese sludge abstracted from a recently established database. Longitudinal trends of OC occurrence were interpreted in the context of national chemical production, usage statistics, and regulations. A total of 105 studies on OCs in U.S. sewage sludge were found, while a total of 159 had been found in China. Among 1,175 OCs monitored for, 23% of all analytes had been monitored in both countries (n = 269), 41% (n = 480) in China only, and the remaining 36% (n = 426) in the U.S. only. On average, concentrations of OCs were 4.0 times higher in U.S. than in Chinese sewage sludge, with the highest detection being observed for alkylphenol ethoxylates. Data from a new binational database on toxic OCs in sewage sludges suggest and reiterates the need for additional chemical monitoring in both countries, risk assessments for emerging OCs contained in sludges destined for application on land, and stronger enforcement of sludge disposal restrictions in China, where as much as 40% of sludge is currently being dumped improperly.

China's rapid growth of both population size and sanitation infrastructure have created a heightened need for responsible management of sewage sludge. We applied liquid chromatography in conjunction with isotope dilution tandem mass spectrometry to measure multiple endocrine disrupting antimicrobials and their transformation products in 100 sewage sludge samples collected across 21 Chinese provinces/districts. Occurrences (detection frequencies) and concentrations (ng/g dry weight) were as follows: triclosan (99%;4-4870), triclocarban (95%;3-43,300), 2'-hydroxy-triclocarban (94%;1-2340), 3'-hydroxy-triclocarban (91%;1-1250), 3,3',4,4'-tetrachlorocarbanilide (100%; 22-580), dichlorocarbanilide (94%;2-23,890), monocarbanilide (92%;2-120), carbanilide (90%;3-1,340), and five parabens: methyl- (98%;2-630), ethyl- (96%;2-170), propyl- (99%;2-27), butyl- (89%;2-11) and benzyl-paraben (7%;2-12). The transformation products of triclocarban were measured for the first time in Chinese wastewater system, and ratios of transformation products to parental triclocarban indicate ongoing triclocarban dechlorination during wastewater treatment. Contaminant profiles and concentrations differed by region, treatment capacity, and wastewater type. Extrapolation of collected data yielded an estimate for the total mass of 13 analytes sequestered in Chinese sewage sludge of 68 t/y with an upper bound of 400 t/y. This China-wide survey established baseline levels of selected antimicrobials in sludges whose current disposal is performed with little regulatory oversight and enforcement.

The illegal disposal of industrial sewage sludge has caused serious environmental pollution. To develop identification technology of industrial sewage sludge based on the characteristic fingerprints is a promising method that is helpful to clarify the responsibility of illegal enterprises. In this study, heavy metal profiles of sewage sludge from industries (including printing and dyeing industry and other industries) and municipal sewage treatment plant located in eastern China were determined, and their performance of classification was evaluated by principal component analysis (PCA) and linear discrimination analysis (LDA). Results showed that heavy metal composition can be an effective tool for distinguishing sewage sludge between printing and dyeing industry and other industries, with an accuracy rate of 82.9%. Meanwhile, heavy metal speciation may be a promising method for identification of printing and dyeing sludge from municipal sewage sludge, the accuracy rate of which reached 100%. Moreover, antimony (Sb) and zinc (Zn) are two indicators, which can be used to identify sewage sludge between printing and dyeing sub-industries, and the accuracy rate was 90%. We concluded that heavy metal profiles may be a precise and promising tool for identification of printing and dyeing sludge. This study developed a potential method for tracing the source of industrial sewage sludge and establishing the identification database of industrial sewage sludge and provided technical support for the government to supervise the illegal dumping and disposal of industrial sewage sludge.

UV-based water treatment processes have been reported to induce genotoxicity during the treatments of surface water, drinking water and artificial water with natural organic matters (NOMs), causing genotoxicity concerns for the drinking water safety. Nitrogenous disinfection byproducts (N-DBPs) were generally reported to be much more genotoxic than their non-nitrogenous analogues, and might be responsible for the genotoxicity in UV processes. Although nitrate-rich water was getting attention for the possibility of genotoxicity and N-DBPs during UV treatments, the impact mechanism of nitrate on the degradation of NOMs, the formation of N-DBPs and genotoxicity has not been explicated. Here simulation experiments of NOM degradation under medium-pressure (MP) UV and MP UV/H2O2 treatments were conducted to explore the effect of nitrate on the molecular characteristics of NOM, the nitrate-derived N-DBPs and the potential genotoxicity through non-targeted analysis and CALUX® reporter gene assays. The results showed that nitrate can accelerate the degradation of NOMs in the MP UV process but inhibit the degradation of NOMs in the MP UV/H2O2 process. During the degradation of NOMs, the molecular compositions varied by the effect of nitrate on oxygen atoms, molecule analogs, and saturation. A total of 105 and 374 nitrate-derived N-DBPs were identified in the MP UV and MP UV/H2O2 treatment, respectively. Most of these N-DBPs contain one nitrogen atom, and the representative features are nitro-, methoxy- (or hydroxyl-) and ester- groups on benzene. No genotoxicity was observed without nitrate spiking, whereas genotoxicity was induced after both MP UV and MP UV/H2O2 treatments when nitrate was spiked, which is worthy of attention for the drinking water safety management.

Urban sustainability is the comprehensive manifestation of development structures and economic aggregates. The current sustainable evaluation of cities from a single aspect cannot comprehensively reflect urban sustainable development. Based on emergy, this study constructs an assessment method of urban sustainability from development structures and economic aggregates. Jiaxing is the case study explored as the sustainable development model of cities in the Yangtze River Delta (YRD) of China. High sustainability of economic aggregates is found in Jiaxing, which is driven by the growth of green GDP. However, the urban development of Jiaxing primarily depends on the input of ecosystem resources, which hinders the sustainability of development structures within Jiaxing. These findings indicate that economic aggregates drive the development of Jiaxing and that the development structures within Jiaxing are unsustainable, resulting from the low sustainability of the natural subsystem and the economic subsystem. As such, it is proposed that industrial structures, development models, and management policies be adopted within cities in the YRD of China in order to promote sustainable development of cities in the YRD of China. This study, therefore, seeks to provide methodological guidance for urban sustainable evaluation.

Xiangjiang (XJ) is a typical urban inland river that serves as a drinking water source, which may be affected by the currently used organochlorine pesticides (CUOCPs) originating from agricultural activities in the vicinity. On this basis, this study comprehensively explored the occurrence and distribution characteristics of CUOCPs in surface water and sediments under long-term precipitation and subsequent floods. Considering the low concentration of CUOCPs in water, a technique combining high-throughput organic analysis with high-volume solid phase extraction (High-throat/Hi-volume SPE) was introduced for effective analysis of CUCOPs. The results showed that the concentration of CUOCPs in the water and sediments of XJ ranged from 2.33 to 6.40 ng L

Ionic liquids (ILs) became emerging pollutants. Their poor degradation and accumulation in organisms urged studies on the long-term effects and also the underlying mechanisms. Currently, 1-butylpyrinium chloride ([bpyr]Cl) was chosen to represent the pyridine-based ILs. Its multi-generational effects were measured on C. elegans for 14 consecutive generations (F1 to F14), and the trans-generational effects were also measured in the great-grand-children (T3 and T3') of F1 and F14. The multi-generational results from F1 to F14 showed that the effects of [bpyr]Cl on the initial and total reproduction and lifespan showed oscillation between inhibition and stimulation. Notably, hormetic effects on reproduction were observed in F7 to F10. The trans-generational effects in T3 and T3' showed different residual consequences between one generational exposure (F1) and multiple generational exposure (F14). Further biochemical analysis showed that the pro/antioxidant status also showed oscillation between inhibition and stimulation. The oscillation levels were greater in superoxide dismutase (SOD), catalase (CAT) and protein carbonyl content (PC) than those in glutathione peroxidase (GSH-Px), reactive oxygen species (ROS) and hydroxyl radical (OH). The pro/antioxidant status contributed to both multi- and trans-generational effects of [bpyr]Cl. Future studies should pay attentions to the long-term influence of ILs and also epigenetic explanations.

In this study, we investigated the occurrence of organophosphate esters (OPEs) in the surface water and sediments of the Xiangjiang (XJ) River, a drinking water source of Changsha City. The total concentrations of five detected OPEs (Σ5OPEs) in surface water and tap water were 6.07-25.3 ng L-1 (average 14.9 ± 4.98 ng L-1), and 23.6 ng L-1, respectively, and four detected OPEs (Σ4OPEs) in sediments were 3.74-27.5 ng g-1 dw (average 12.1 ± 6.48 ng g-1 dw). Tris-2-chloroisopropyl phosphate (TCIPP) was the dominant contributor in water and sediment samples, accounting for over 40% of ΣOPEs. A particular flood event during July-August 2020 reduced the level of OPEs in river water, leading to generally uniform OPE concentrations in surface water and sediment samples from the upper, middle, and lower reaches of XJ. Principal component analysis-multiple linear regression (PCA-MLR) results indicated that the main sources of OPEs in the surface water and sediments of XJ were emissions of waste-water treatment plants and anthropocentric activities. The results of ecological and human health risk assessments indicated that all OPEs posed a low or negligible ecological risk for algae, daphnia, and fish, and negligible risk for human health. Interestingly, the concentration and human health risk of OPEs in a composite tap water sample was generally higher than those in river water samples, indicating possible OPE contamination from water treatment processes or transportation through pipe networks.

The polar regions had long been regarded as healthy ecosystems free of any hazardous traces left by human activity. Unfortunately, since the intensification of industrial activities leading to huge releases into environment, anthropogenic pollutants through global atmospheric and ocean currents were found with more or less high concentrations in all polar ecosystem compartments. Among these pollutants, one of the most dangerous categories is persistent organic pollutants (POPs). Since polar ecosystems are fragile and have a limited capacity for resilience, their contamination can generate unforeseeable consequences that can affect global cycles. Our work aims to compile data collected through a review of studies carried out within the framework of POPs evolution in polar regions, and then to compare them in order to identify future improvements to be made within the framework of POPs monitoring in the Arctic and Antarctic. According to our observations, POPs concentrations in all ecosystem compartments in Arctic are much higher than in Antarctica. Moreover, global warming influencing the abiotic factors of diffusion and mobility of POPs has led to a massive revolatization of POPs in the Arctic as well as an increase in their concentrations in large mammals. We also noted a lack of availability of consistent and continuous long-term data in Antarctic, which is why an ambiguity persists in the understanding of the POPs contamination routes, their evolution as well as the application of projection models.

Globally, there is a serious issue in carbon stock due to high deforestation and the loss of land, limited carbon storage pools in aboveground and underground forests in different regions, and increased carbon emissions to the atmosphere. This review paper highlights the impact of exclosures on above and below ground carbon stocks in biomass as a solution to globally curb carbon emissions. The data has been analyzed dependent on the Intergovernmental Panel on Climate Change (IPCC) guidelines, the Food and Agriculture Organization (FAO) Forest Resource Assessment report (FRA, 2020), and scientific journal publications mostly from the last decade, to show the research results of carbon stock and the impact of exclosures, particularly the challenges of deforestation and erosion of land and opportunities of area exclosures to provide a general outlook for policymakers. Overall, the world’s forest regions are declining, and although the forest loss rate has slowed, it has still not stopped sufficiently because the knowledge and practice of exclosures are limited. The global forest loss and carbon stock have decreased from 7.8 million ha/yr to 4.7 million ha/yr and from 668 gigatons to 662 gigatons respectively due to multiple factors that differ across the regions. However, a move toward natural rehabilitation and exclosures to reduce the emissions of Greenhouse Gas (GHGs) is needed. In the global production of carbon, the exclosure of forests plays an important role, in particular for permanent sinks of carbon.

In this study, we reported the occurrence of eight organophosphorus pesticides (OPPs) in the East China Sea. Forty samples were collected and analysed with a high volume solid phase extraction method (Hi-throat/Hi-volume SPE) in the early summer of 2020. All the target OPPs were detected in the surface water at one or more stations in the East China Sea, and the concentrations of ΣOPPs were in the range 0.0775–3.09 ng/L (mean: 0.862 ± 0.624 ng/L). Terbufos sulfone and fenthion were the main pollutants in this area, probably resulting from pesticide use in China and other countries. The off-shore input from coastal regions was suggested to be a major source of OPP pollution in the East China Sea, and the movement of ocean currents played an important role in their transportation because around 0.86 t OPPs passed through the Tsushima Strait from the East China Sea each month. An ecological risk assessment showed that these OPPs presented a high risk to species in the East China Sea, whereas they posed no health risk to humans under both the median and high exposure scenario.

Organophosphate esters (OPEs) are typical industrial additives widely applied in various industrial and household products, but they may pollute drinking water. In the present study, the occurrence of OPEs in drinking water was analyzed. For this purpose, 25 drinking water samples were collected from households in 25 cities in China. The concentrations of OPEs were accurately determined according to a high-throughput organic analysis testing combined with high-volume solid phase extraction (Hi-throat/Hi-volume SPE) technique. Through this technique, nine OPEs were detected, with spiked recoveries from 77% to 101%, and their total concentrations (ΣOPEs) ranging from 46.8 to 251 (average 126) ng L−1. The detection frequencies of the selected OPEs determined via Hi-throat/Hi-volume SPE were 88.0%–100%, which are much higher than those previously reported. The limit of detections of the OPEs was low at 20 L). OPEs in drinking water presented a decreasing trend from cities in coastal provinces to inland cities of China. Redundancy analysis showed that the concentrations of OPEs in drinking water were significantly influenced by economic–demographic influencing factors. The non-carcinogenic and lifetime carcinogenic risks (non-CR and CR) of the analyzed OPEs in drinking water were negligible for urban residents in China.

Bisphenol A (BPA) is a well-known xenoestrogen, and UV/H

Rapid urbanization created unique urban environment with a characteristic of dramatic modification of land cover, consequently causing profound perturbations in the transport and fate of pollutants in urban ecosystem. Taking a hyper-urbanization city (Shanghai) as an example to reveal the influence of urbanization development on pollutant footprint, this study reconstructed and compared historical evolutions of elemental carbon (EC) and polycyclic aromatic hydrocarbons (PAHs) based on two lake sediment cores (DSL: Dianshan Lake; LXL: Luxun Lake) from early- and newly-urbanized areas, respectively. Historical fluxes of EC and total PAH (Σ16PAHs) showed similar and sharply fluctuant increases occurring after the 1950s in the DSL core later than the LXL core after the 1900s. In modern times (after 2000), the mean fluxes of EC and Σ16PAHs in the LXL core were 2.68- and 1.38-fold greater than those in the DSL core, respectively, indicating the stronger influence from more intensive human activities and longer industrial history in early urbanized area. Based on the significant correlations among socioeconomic factors with EC and Σ16PAH fluxes, the extended STIRPAT (stochastic impacts by regression on population, affluence and technology) models were successfully constructed, revealing that significance of these driving factors were in the order of population > the proportion of heavy industry > coal consumption > gross domestic product (GDP) per capita > vehicle amount. In general, the obvious discrepancy in historical stage and intensity of sedimentary EC and PAH accumulations implied that some newly fast-developing cities still have a chance to adjust urban development strategy to avoid more serious pollution.

With the recent restrictions of the use of high-toxic organochlorine pesticides (OCPs), other OCPs with possibly lower toxicities have become increasingly popular, herein referred to as the currently used organochlorine pesticides (CUOCPs). Drinking water is one of the most valuable resources for the preservation of life, and it is susceptible to pollution by CUOCPs. However, there are no existing data on the occurrence and human exposures to CUOCPs in drinking water, thus there are growing concerns over the potential health hazards of these undetected chemicals. In this study, an emerging high-throughput organic analysis testing combined with a high-volume solid-phase extraction technique was utilized to explore the potential presence and human exposures to the CUOCPs in two types of drinking water (namely, tap water (TW) and bottled water (BW)) samples from eight cities in the Yangtze River Delta urban agglomeration, China. The study overcomes the deficiencies of recent investigations on the trace/ultra-trace organic pollution of drinking water. The results reveal that the total concentrations of the eighteen target CUOCPs (Σ18CUOCPs) in the TW and BW samples were 2.68–11.7 ng L–1 (mean 6.11 ± 2.20 ng L–1) and 0.63–2.75 ng L–1 (mean 1.37 ± 0.64 ng L–1), respectively. The concentrations of most of the detected CUOCPs in BW were significantly lower than those in TW, indicating generally lower CUOCP pollution levels in BW. This is possibly related to the higher source-water quality and more advanced treatment processes for BW production. Meanwhile, the concentrations of the ΣCUOCPs in TW from the urban areas of the studied cities were generally higher than those from the suburban areas. This was mainly attributed to the concentrations of the dominant CUOCPs in TW, such as tetradifon and dichlobenil. However, with the rapid urbanization of the cities, the concentrations of other individual CUOCPs in TW showed no significant differences between the samples from the urban and suburban areas. Besides, the estimated daily intake of the CUOCPs from TW was approximately 0.5 ng (kg of body weight (bw))−1 d−1 for males and females, which is considerably higher than the corresponding approximate value for BW (∼0.1 ng (kg of bw)−1 d−1). Thus, the study revealed that the harmful exposure to CUOCPs was lower in BW than in TW.

Perfluoroalkyl acids (PFAAs) have been found to be ubiquitously disseminated in the environment due to their widespread use in recent decades. In this study, the occurrence and spatiotemporal distribution of PFAAs in the surface water of Huangpu River, Shanghai, China were investigated from 2012 to 2014. The total concentration of 14 PFAAs (ΣPFAAs) ranged from 39.8 to 596.2 ng L −1 , with a mean value of 226.3 ng L −1 . Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were dominant, with their mean concentrations of 139.6 and 46.5 ng L −1 , respectively. The concentration of ΣPFAAs increased greatly downstream especially in the lower reach of an industrial and urbanized area. Samples collected in different seasons were used to analyze the seasonal variation. The results showed that higher concentration of ΣPFAAs occurred in the wet season, especially downstream. Therefore, industrial discharges, municipal wastewater and surface runoff were identified as major potential sources. The annual discharge load of ΣPFAAs from Huangpu River to Yangtze River was estimated to be 2263.4 kg yr −1 . The hazard assessment suggested that the contamination of PFAAs in Huangpu River could pose risks to the aquatic environment and drinking water safety, which should draw more attention.

Nanoparticle (NP) assessment in sludge materials, although of growing importance in eco- and biotoxicity studies, is commonly overlooked and, at best, understudied. In the present study, sewage sludge samples from across the mega-city of Shanghai, China were investigated for the first time using a sequential extraction method coupled with single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) to quantify the abundance of metal-containing NPs in the extraction fractions and transmission electron microscopy to specifically identify the nanophases present. In general, most sludges observed showed high concentrations of Cr, Cu, Cd, Ni, Zn, and Pb, exceeding the maximum permitted values in the national application standard of acid soil in China. NPs in these sludges contribute little to the volume and mass but account for about half of the total particle number. Based on electron microscopy techniques, various NPs were further identified, including Ti-, Fe-, Zn-, Sn-, and Pb-containing NPs. All NPs, ignored by traditional metal risk evaluation methods, were observed at a concentration of 10

Antibiotic resistance genes (ARGs) raise public concern as emerging contaminants. The abundance and variation of 11 ARGs, intI1 and 16S rRNA gene were deciphered using quantitative PCR (qPCR) in two drinking water treatment systems that include river, wetland, drinking water treatment plants (DWTPs) and tap water from the Yangtze River Delta. The influencing factors for ARG abundance in river water were also explored. All investigated genes were detected in river water and there was no significant difference between the two systems, with sulfonamide ARGs occupying the highest abundance. Temperature had a significant effect on the ARG distribution based on permutational multivariate analysis of variance (PERMANOVA). Further Spearman analysis demonstrated that temperature was strongly correlated with the abundance of sul1, sul2, tetA and tetC, and these genes were significantly correlated with environmental factors (including temperature, total organic carbon (TOC) and dissolved oxygen (DO)). Considering the frequency and abundance of ARGs, as well as their correlation with other genes, sul1, sul2, tetA and tetC could be used as indicators of ARGs in river water. No significant reduction was noted for the absolute abundance of ARGs from river water to wetland water. Principle coordinates analysis (PCoA) combined with PERMANOVA revealed that drinking water treatment was responsible for reducing 16S rRNA gene and ARG abundance resulting in 3-log reductions. However, it should be noted that after transportation of distribution pipeline, both 16S rRNA gene and ARGs still detected in tap water, which indicated persistence of ARGs and will require further research.

The risk associated with human exposure to short-chain chlorinated paraffins (SCCPs) via dietary intake are of great concern because of the bioaccumulation potential of SCCPs in biota and adverse effects. Fish are an important food source for human beings. However, there is a paucity of studies on human exposure to SCCPs via fish consumption. In this study, SCCPs were measured in frequently consumed river fish from the Pearl River Delta, and farmed freshwater fish and wild sea fish from the Yangtze River Delta. Lipid-normalized SCCP levels in river fish ranged from 3000 to 41,000 ng/g lipid weight (lw), with an average of 16,000 ± 12,000 ng/g lw. SCCP concentrations in farmed fish were significantly lower than those in river fish (p 0.05), but significantly higher than those in sea fish (p 0.05). Homologue patterns of SCCPs in river fish, farmed fish and sea fish were similar, with C

Bisphenol A (BPA) is a well-known xenoestrogen, and UV/H2O2 advanced oxidation process (AOP) is one of the most effective technologies to remove BPA from water. Using BPA spiked tap water, a batch-scale photochemical experiment was conducted to investigate whether BPA can pose a genotoxicity concern during the medium pressure (MP) UV/H2O2 treatment and the post-chloramination. Samples at different UV exposure and post-chloramination durations were collected and analyzed by CALUX® gene reporter assays regarding estrogen receptor α (ERα) and p53 transcriptional activity. MP UV/H2O2 process did not cause extra estrogenic effects from the degradation of BPA, whereas genotoxicity occurred when the treated water was exposed with monochloramine. Seven frequently reported nitrogenous disinfection byproducts (N-DBPs) were detected, but none of them were responsible for the observed genotoxicity. Employed with gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), four compounds possibly contributed to the genotoxicity were tentatively identified and two of them with aminooxy- or cyano- group were considered as “new” N-DBPs. This study demonstrated that by-products differ from their parent compounds in toxicity can be formed in the UV oxidation with post-disinfection process, which should become a cause for concern.

Rapid industrialization and urbanization has caused large emission and potential contamination of mercury (Hg) in urban environment. However, little is known about the impact of socioeconomic factor on Hg accumulation in sediment. In the present study, historical record of anthropogenic Hg deposition of Shanghai was reconstructed by using three sediment cores from three park lakes (C1: Luxun Park; C2: Fuxing island Park; C3: Xinjiangwan Park). Meanwhile, the influence of socioeconomic factor to Hg emissions and sedimentary record was calculated based on an extended STIRPAT (stochastic impacts by regression on population, affluence and technology) model. The profiles of Hg levels and fluxes in the three sediment cores showed that Shanghai has recently undergone urbanization. The anthropogenic Hg fluxes exhibited fluctuant increases from ∼1900 to present and accelerated after the establishment of the People's Republic of China in 1949 and the implementation of reform and opening up policy in 1978. The mean flux ratios of Hg in post-2000 were 2.2, 12, and 2.7 in the C1, C2 and C3 cores, respectively. The extended STIRPAT model was constructed based on strong positive relationships between socioeconomic factors and Hg fluxes, revealing that the proportion of coal consumption, the urbanization rate, and the proportion of heavy industry were the three most important driving factors for Hg accumulations in urban sediment of Shanghai.

Semi-volatile organic compounds (SVOCs) are ubiquitous and toxic environmental pollutants, and have recently attracted much research attention. However, their occurrence in tapwater and the associated potential health risks have not been thoroughly studied. This work examined 26 household tapwater samples collected in 26 Chinese cities during August and September 2019. Concentrations of 79 SVOCs, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polychlorobenzenes (CBs), were determined using an emerging method of high throughput organic analysis testing combined with high volume solid phase extraction (Hi-throat/Hi-volume SPE). Total concentrations of PAHs, PCBs, OCPs, and CBs were in the ranges 8.70–103 ng L−1 (average 42.1 ng L−1), 61.6–434 pg L−1 (average 274 pg L−1), 13.1–266 pg L−1 (average 59.8 pg L−1), and 3.5–83.0 pg L−1 (average 13.8 pg L−1), respectively. PAHs were the dominant SVOCs, with concentrations 10–100 times those of PCBs, OCPs, and CBs. All the studied SVOCs had concentrations deemed acceptable by Chinese national tapwater standards. These measured SVOCs displayed little spatial variation across China, but were significantly correlated with the size of the economy and population of each city. The human non-carcinogenic and carcinogenic risks associated with the studied SVOCs in Chinese tapwater are negligible.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants, posing potentially serious threats to human health. This study analyzed compositional characteristics, sources, and carcinogenic risks of PAHs in the atmospheric gas phase at an urban site in Shanghai, East China. Seventy-four gas phase samples were collected during the warm months of May–October 2018 using a high-volume solid phase extraction (Hi-volume SPE) technique. The total concentration of sixteen priority PAHs (ΣPAHs) was in the range of 5.54–182.05 ng m−3 (average 34.47 ng m−3) and the total of seven carcinogenic PAHs (ΣCPAHs) was in range of 0.03–1.49 ng m−3 (average 0.48 ng m−3), accounting for 1.47% of ΣPAHs and indicating low carcinogenic potential. Redundancy analyses indicated positive correlations between ΣPAHs and air quality, and ΣCPAHs and average high temperature, and a negative correlation between ΣPAHs and wind speed. Four possible sources, namely petroleum and petrogenic sources, traffic emissions, coal combustion, and mixed gasoline and coal combustion sources, were identified by positive matrix factorization (PMF), accounting for 62.84%, 19.31%, 10.15%, and 7.69% of ΣPAHs, respectively. The overall lifetime lung cancer risk (LLCR) through inhalation of PAHs was estimated to be at a low risk level of 1.61 × 10−5. The LLCR based on PMF apportionment decreased in the order of mixed gasoline and coal combustion sources (47.07%) > traffic emissions (35.10%) > petroleum and petrogenic sources (11.06%) > coal combustion (6.74%). This study demonstrates the effectiveness of Hi-volume SPE in collecting and analyzing atmospheric gas phase PAHs.

Rapid urbanization in Shanghai over the past century has led to increased resource and energy consumption, in turn leading to the release of significant amounts of toxic pollutants into the urban environment. In order to investigate historical variations in atmospheric metal emissions from typical combustion sources in Shanghai, historical emissions of Pb and Hg from coal-fired sectors (coal-fired power plant, industrial sector, and domestic use) and vehicle exhaust in Shanghai during the period 1949-2015 were estimated, based on consumption of fossil fuels (coal and gasoline) and emission factors. Results showed that Pb and Hg emissions exhibited rapidly fluctuating increases from 1949 to the 1980s or 1990s, before beginning to decrease sharply due to various pollution control measures. Hg emissions from coal-fired sources played a dominant role during the 1980-2015 period, contributing a high proportion (87.5%-99.7%) to the total. The dominant sources of atmospheric Pb emissions have experienced historical variations. Coal-fired emissions became the major contributor (78.2%-83.5% of total) following omission of leaded gasoline from the Shanghai market since 1997. However, the rapid increase of gasoline consumption since 2005 has led to gasoline-fired emissions again becoming the main contributor (55.5%-79.1%).

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), are frequently detected in biota from Antarctica, whereas no data are available for their replacements, such as novel flame retardants (N-FRs). This study presented the occurrence of several N-FRs, PBDEs, and PCBs in tissue samples of an Antarctic rock cod (Trematomus bernacchii), a young gentoo penguin (Pygoscelis papua), and a brown skua (Stercorarius antarcticus) collected from King George Island. The total concentrations of N-FRs (ΣN-FRs; mean: 931 pg/g dry weight (dw)) were comparable to PBDEs (Σ8PBDEs; 681 pg/g dw), which were much lower than PCBs (ΣDL-PCBs; 12,800 pg/g dw). Overall, skua contained two to three orders of magnitude higher contamination than penguin and fish. In the future, more attention should be focused on the fate of N-FRs in Antarctica, where usages have increased since PBDEs were banned. To our knowledge, this is the first report of N-FRs in biota from Antarctica.

This study evaluated the levels and spatial distribution of PBDEs in 9 typical offices in Shanghai, China through the sample analysis of air and settled dust (floor dust, desktop dust and dust in computer case). PBDEs in air ranged from 93 to 322 pg/m(3), while the PBDEs levels in dust varied from 247 to 3.3 × 10(4) ng/g. Spatial variability of PBDEs in office dust was evident and likely influenced by air exchange and the use of electronic devices. A significant positive linear correlation was observed between the power usage rate and PBDE levels in both office air (R(2) = 0.81) and settled dust (R(2) = 0.94). The PBDEs exposure via inhalation and dust ingestion were both analyzed to estimate the life-time cancer risk, which is 1.34 × 10(-22) to 7.16 × 10(-22), significantly lower than the threshold level (10(-6)). Non-cancer risk indicated by the hazard index (1) is also low in current exposure conditions.

To explore the influence of rapid urbanization development on the accumulation of 16 priority PAHs in urban environment, thirty-three surface sediments from city lakes in different urbanized areas of Shanghai were collected to evaluate the occurrence characteristic and source apportionment of PAHs. The concentrations of Σ16PAHs in lake surface sediments ranged from 55.7 to 4928 ng g−1 with a mean value of 1131 ng g−1 (standard deviation, 1228 ng g−1), of which 4-, 5- and 6-ring PAHs were the dominant components. Spatial distribution of PAHs in lake surface sediments showed a significantly declining trend along with a decreasing urbanization gradient (one-way ANOVA, p

Background: In utero polybrominated diphenyl ethers (PBDEs) exposure has been associated with adverse fetal growth. Alterations in placental DNA methylation might mediate those adverse effects. Objectives: To examine the associations between in utero PBDEs exposure and DNA methylation in human placenta. Methods: Eighty apparently healthy mother-newborn pairs delivering at the Second Affiliated Hospital of Wenzhou Medical College were enrolled in this study. Placental DNA methylation of LINE1, NR3C1 and IGF2 was measured by quantitative polymerase chain reaction-pyrosequencing. In utero PBDEs exposure was assessed by measuring umbilical cord blood PBDEs concentrations. Results: For LINE-1, higher levels of BDE-66 exposure were associated with decreased DNA methylation (β = −0.9, 95% CI, −1.8 to −0.1); For NR3C1, BDE-153 concentrations was significantly inversely associated with DNA methylation (β = −2.0, 95% CI, −3.7 to −0.2); For IGF2, elevated concentrations of both BDE-153 (β = −1.7; 95% CI, −3.0 to −0.4) and BDE-209 (β = −1.0; 95% CI, −1. 9 to −0.1) were significantly associated with decreased DNA methylation. Conclusions: We found that placental DNA methylation is associated with in utero PBDEs exposure. Changes in placental DNA methylation might be part of the underlying biological pathway between in utero PBDEs exposure and adverse fetal growth. Keywords: PBDEs, DNA methylation, Fetal growth, Placenta

Aquaculture is a booming industry in the world and China is the largest producer and exporter of aquatic products. To prevent and treat diseases occurred in aquaculture, antibiotics are widely applied. However, the information of antibiotics used in Chinese aquaculture is still limited. Based on peer-reviewed papers, documents, reports, and even farmer surveys, this review summarized antibiotics used in Chinese aquaculture. In 2014, more than 47.4 million tonnes of farmed aquatic products were produced in mainland China. The outputs in the east and south parts of China can reach as much as 600 times higher than those in the northwest areas, which is clearly separated by the "Hu Line" - a line that marks a striking difference in the distribution of population. A total of 20 antibiotics belonging to eight categories have been reported for use, mainly via oral administration. However, only 13 antibiotics have been authorized for application in Chinese aquaculture and 12 antibiotics used are not authorized. Totally, 234 cases on antibiotic residues in Chinese aquatic products were recorded, including 24 fish species, eight crustacean species, and four mollusk species. Thirty-two antibiotics have been detected in aquatic products; quinolones and sulfonamides were the dominated residual chemicals. For specific compound, ciprofloxacin, norfloxacin, and sulfisoxazole have the highest concentrations. Except for a few cases, all residual concentrations were lower than the maximum residue limits. Through the consumption of aquatic products tainted by antibiotics, humans may acquire adverse drug reactions or antibiotic-resistant bacteria. However, the risk of antimicrobial resistance in human body, when exposed to antibiotics at sub-inhibitory concentrations, has not been exhaustively considered in the risk assessment. In addition, a national comprehensive investigation on the amount of antibiotics used in Chinese aquaculture is still needed in future studies.

Aquaculture in mangrove wetlands has been developed rapidly, causing various environmental problems (e.g., antibiotic residue). In the present study, the levels and distributions of a well-known class of antibiotics (fluoroquinolones; FQs), including norfloxacin (NOR), ciprofloxacin (CIP), and enrofloxacin (ENR), were examined in sediment and mangrove plant (Aegiceras corniculatum) from a mangrove wetland in the Zhanjiang Mangrove National Nature Reserve, South China. NOR and CIP were detected in all sediment samples, with concentrations ranging from 4.3 to 64.2 ng/g and from 7.62 to 68.5 ng/g on a basis of dry weight (dw), respectively, whereas ENR was found with relatively lower frequency (

The production of sewage sludge is increasing in China but with unsafe disposal practices, causing potential risk to human health and the environment. Using literature from the past 30 years (N = 159), we conducted a meta-analysis of organic contaminants (OCs) in Chinese sludge. Most data were available from developed and populated regions, and no data were found for Tibet. Since 1987, 35 classes of chemicals consisting of 749 individual compounds and 1 mixture have been analyzed, in which antibiotics and polycyclic aromatic hydrocarbons (PAHs) were the most targeted analytes. For 13 classes of principal OCs (defined as chemicals detected in over five studies) in sludge, the median (expressed in nanograms per gram dry weight) was the highest for phthalate esters (27 900), followed by alkylphenol polyethoxylates (12 000), synthetic musks (5800), antibiotics (4240), PAHs (3490), ultraviolet stabilizers (670), bisphenol analogs (160), organochlorine pesticides (110), polybrominated diphenyl ethers (100), pharmaceuticals (84), hormones (69), perfluorinated compounds (21), and polychlorinated biphenyls (15). Concentrations of PAHs in sludges collected between 1998 and 2012 showed a decreasing trend. Study findings suggest the need for a Chinese national sewage sludge survey to identify and regulate toxic OCs, ideally employing both targeted as well as nontargeted screening approaches.

Freely dissolved polycyclic aromatic hydrocarbons (PAHs) were monitored in seven inland lakes of Antarctica by a polyethylene (PE)-based passive sampling technique, with the objective of tracking human footprints. The measured concentrations of PAHs were in the range of 14-360 ng L(-1) with the highest values concentrated around the Russian Progress II Station, indicating the significance of human activities to the loading of PAHs in Antarctica. The concentrations of PAHs in the inland lakes were in the upper part of the PAHs levels in aquatic environments from remote and background regions across the globe. The composition profiles of PAHs indicated that PAHs in the inland lakes were derived mainly from local oil spills, which was corroborated by a large number of fuel spillage reports from ship and plane crash incidents in Antarctica during recent years. Clearly, local human activities, rather than long-range transport, are the dominant sources of PAH contamination to the inland lakes. Finally, the present study demonstrates the efficacy of PE-based passive samplers for investigating PAHs in the aquatic environment of Antarctica under complex field conditions.

Environmental risks of polybrominated diphenyl ethers (PBDEs) in sewage sludge are assessed based on the concentration by exhaustive extraction, which is a likely overestimation of the pool available to exposed organisms. This study evaluated the bioaccessibility of PBDEs in sewage sludge from Shanghai using a 3-compartment model and a 6-d Tenax extraction. The very slowly fraction contributed 56-88% of total PBDEs in spiked sludge, whereas the rapidly desorbing fraction contributed only 1.1-10%. For the same PBDE congener, the rapidly desorbing fractions for sewage sludge measured in the present study were lower than those for sediment. The bioaccessible concentrations of PBDEs were 2.3-56 ng/g dry weight in sewage sludge from Shanghai, which represented 5.2% of the concentration determined by exhaustive (Soxhlet) extraction. BDE-209 was the predominant congener in sludge, contributing to 63% of the total. Moreover, the Ratio between 6-h Tenax and Soxhlet concentrations (T/S Ratio, indicating bioaccessibility) was lower in sludge generated from industrial wastewater treatment compared to sludge from facilities that treated mostly domestic wastewater. The T/S Ratio of PBDE congeners was related to KOW, specifically as KOW increases, the T/S Ratio decreased. These results will improve understanding of the fate and potential toxicity of PBDEs during land and/or landfill application of sewage sludge.

To evaluate risk via inhalation exposure of polybrominated diphenyl ethers (PBDEs) in office environment, thirty-six pairs air samples including PM2.5 (particles with aerodynamic diameter less than 2.5 μm), PM10 (particles with aerodynamic diameter less than 10 μm), total suspended particles (TSP) with matching gas phase were collected in office environment in Shanghai, China. The average concentrations of PM2.5, PM10 and TSP were 20.4, 27.2 and 50.3 μg/m3, respectively. Σ15PBDEs mean concentrations in PM2.5, PM10, TSP and gas phase were 51.8, 110.7, 148 and 59.6 pg/m3, respectively. Much more PBDEs distributed in fine fractions than coarse ones. PBDEs congener profiles found in PM2.5, PM10 and TSP (dominated by BDE-209) were different from that in gas phase (dominated by the tri- to penta-BDEs). Approximately 3.20 pg/kg/d PM2.5 bound PBDEs can be inhaled into the lung; 3.62 pg/kg/d PM10-PM2.5(particles with aerodynamic diameter of 2.5-10 μm) bound PBDEs tended to be deposited in the upper part of respiratory system, and the intake of PBDEs via gas-phase was 2.74 pg/kg/d. The exposure of PBDEs was far below the minimal risk levels (MRLs), indicating lower risk from PBDEs via inhalation in the studied office in Shanghai.