Search

Short-chain chlorinated paraffins (SCCPs) have attracted attention because of their toxicological potential in humans and wildlife at environmentally relevant doses. However, limited information is available regarding mechanistic differences across species in terms of the biological pathways that are impacted by SCCP exposure. Here, a concentration-dependent reduced human transcriptome (RHT) approach was conducted to evaluate 15 SCCPs in HepG2 cells and compared with our previous results using a reduced zebrafish transcriptome (RZT) approach in zebrafish embryos (ZFEs). Generally, SCCPs induced a broader suite of biological pathways in ZFEs than HepG2 cells, and all of the 15 SCCPs were more potent in HepG2 cells compared to ZFEs. Despite these general differences, the transcriptional potency of SCCPs in both model systems showed a significant linear relationship (p = 0.0017, r2 = 0.57), and the average ratios of transcriptional potency for each SCCP in RZT to that in RHT were ∼100,000. C10H14Cl8 was the most potent SCCP, while C10H17Cl5 was the least potent in both ZFEs and HepG2 cells. An adverse outcome pathway network-based analysis demonstrated model-specific responses, such as xenobiotic metabolism that may be mediated by different nuclear receptor-mediated pathways between HepG2 cells (e.g., CAR and AhR activation) and ZFEs (e.g., PXR activation). Moreover, induced transcriptional changes in ZFEs associated with pathways and molecular initiating events (e.g., activation of nicotinic acetylcholine receptor) suggest that SCCPs may disrupt neural development processes. The cross-model comparison of concentration-dependent transcriptomics represents a promising approach to assess and prioritize SCCPs.

Because industrial wastewater contains numerous chemicals and transformation products (TPs), it is important to select efficient wastewater treatments to remove toxic pollutants and their related t...

Anammox bacteria have been detected in various ecosystems, but their occurrence and community composition along the shipping channels have not been reported. In this study, anammox bacteria were recovered by PCR-amplified biomarker hzsB gene from the genomic DNA of the sediment samples. Phylogenetic tree revealed that Candidatus Scalindua and Ca. Brocadia dominated the anammox community of the Hong Kong channels; Ca. Scalindua spp. was present abundantly at the sites farther from the shore, whereas Ca. Jettenia and Ca. Kuenenia were detected as the minor members in the estuarine sediments near the shipping terminals. The highest values of Shannon–Wiener index and Chao1 were identified in the sediments along the Urmston road (UR), suggesting the highest α-diversity and species richness of anammox bacteria. PCoA analysis indicated that anammox bacterial communities along UR and Tai Hong (TH) channel were site-specific because these samples were grouped and clearly separated from the other samples. The maximum diversity of anammox bacteria was detected in UR samples, ranging from 6.28 × 105 to 1.28 × 106 gene copies per gram of dry sediment. A similar pattern of their transcriptional activities was also observed among these channels. Pearson’s moment correlation and redundancy analysis indicated that NH4+-N was a strong factor shaping the community structure, which showed significant positive correlation with the anammox bacterial abundance and anammox transcriptional activities (p 0.8). Also, NH4+-N, (NO3− + NO2−)-N, and NH4+/NOX were additional key environmental factors that influenced the anammox community diversity and distribution. This study yields a better understanding of the ecological distribution of anammox bacteria and the dominant genera in selective niche.

In the view of studying humus formation in corn straw under the action of microorganism, three fungi (Trichoderma reesei, Trichoderma harzianum, Phanerochaete chrysosporium) were selected to compar...

Deep shale layer in the Lower Silurian Longmaxi Formation, southern Sichuan Basin is the major replacement target of shale gas exploration in China. However, the prediction of “sweet-spots” in deep shale gas reservoirs lacks physical basis due to the short of systematic experimental research on the physical properties of the deep shale. Based on petrological, acoustic and hardness measurements, variation law and control factors of dynamic and static elastic properties of the deep shale samples are investigated. The study results show that the deep shale samples are similar to the middle-shallow shale in terms of mineral composition and pore type. Geochemical characteristics of organic-rich shale samples (TOC > 2%) indicate that these shale samples have a framework of microcrystalline quartz grains; the intergranular pores in these shale samples are between rigid quartz grains and have mechanical property of hard pore. The lean-organic shale samples (TOC < 2%), with quartz primarily coming from terrigenous debris, feature plastic clay mineral particles as the support frame in rock texture. Intergranular pores in these samples are between clay particles, and show features of soft pores in mechanical property. The difference in microtexture of the deep shale samples results in an asymmetrical inverted V-type change in velocity with quartz content, and the organic-rich shale samples have a smaller variation rate in velocity-porosity and velocity-organic matter content. Also due to the difference in microtexture, the organic-rich shale and organic-lean shale can be clearly discriminated in the cross plots of P-wave impedance versus Poisson's ratio as well as elasticity modulus versus Poisson's ratio. The shale samples with quartz mainly coming from biogenic silica show higher hardness and brittleness, while the shale samples with quartz from terrigenous debris have hardness and brittleness less affected by quartz content. The study results can provide a basis for well-logging interpretation and “sweet spot” prediction of Longmaxi Formation shale gas reservoirs.

Corn straw return to the field is a vital agronomic practice for increasing soil organic carbon (SOC) and its labile fractions, as well as soil aggregates and organic carbon (OC) associated with water-stable aggregates (WSA). Moreover, the labile SOC fractions play an important role in OC turnover and sequestration. The aims of this study were to determine how different corn straw returning modes affect the contents of labile SOC fractions and OC associated with WSA. Corn straw was returned in the following depths: (1) on undisturbed soil surface (NTS), (2) in the 0–10 cm soil depth (MTS), (3) in the 0–20 cm soil depth (CTS), and (4) no corn straw applied (CK). After five years (2014–2018), soil was sampled in the 0–20 and 20–40 cm depths to measure the water-extractable organic C (WEOC), permanganate oxidizable C (KMnO4-C), light fraction organic C (LFOC), and WSA fractions. The results showed that compared with CK, corn straw amended soils (NTS, MTS and CTS) increased SOC content by 11.55%–16.58%, WEOC by 41.38%–51.42%, KMnO4-C and LFOC by 29.84%–34.09% and 56.68%–65.36% in the 0–40 cm soil depth. The LFOC and KMnO4-C were proved to be the most sensitive fractions to different corn straw returning modes. Compared with CK, soils amended with corn straw increased mean weight diameter by 24.24%–40.48% in the 0–20 cm soil depth. The NTS and MTS preserved more than 60.00% of OC in macro-aggregates compared with CK. No significant difference was found in corn yield across all corn straw returning modes throughout the study period, indicating that adoption of NTS and MTS would increase SOC content and improve soil structure, and would not decline crop production.

1,4-Dioxane is a widely used industrial solvent that has been frequently detected in aquatic environments. However, the hepatotoxicity of long-term dioxane exposure at environmentally relevant concentrations and underlying mechanisms of liver damage remain unclear. In this study, male mice were exposed to dioxane at concentrations of 0.5, 5, 50, and 500 ppm for 12 weeks, followed by histopathological examination of liver sections and multiomics investigation of the hepatic transcriptome, serum metabolome, and gut microbiome. Results showed that dioxane exposure at environmentally relevant concentrations induced hepatic inflammation and caused changes in the hepatic transcriptome and serum metabolic profiles. However, no inflammatory response was observed after in vitro exposure to all concentrations of dioxane and its in vivo metabolites. The gut microbiome was considered to be contributing to this apparently contradictory response. Increased levels of lipopolysaccharide (LPS) may be produced by some gut microbiota, such as Porphyromonadaceae and Helicobacteraceae, after in vivo 500 ppm of dioxane exposure. LPS may enter the blood circulation through an impaired intestinal wall and aggravate hepatic inflammation in mice. This study provides novel insight into the underlying mechanisms of hepatic inflammation induced by dioxane and highlights the need for concerns about environmentally relevant concentrations of dioxane exposure.

Weiyuan shale gas play is characterized by thin high-quality reservoir thickness, big horizontal stress difference, and big productivity differences between wells. Based on integrated evaluation of shale gas reservoir geology and well logging interpretation of more than 20 appraisal wells, a correlation was built between the single well test production rate and the high-quality reservoir length drilled in the horizontal wells, high-quality reservoir thickness and the stimulation treatment parameters in over 100 horizontal wells, the dominating factors on horizontal well productivity were found out, and optimized development strategies were proposed. The results show that the deployed reserves of high-quality reservoir are the dominating factors on horizontal well productivity. In other words, the shale gas well productivity is controlled by the thickness of the high-quality reservoir, the high-quality reservoir drilling length and the effectiveness of stimulation. Based on the above understanding, the development strategies in Weiyuan shale gas play are optimized as follows: (1) The target of horizontal wells is located in the middle and lower parts of Longyi 11 (Wei202 area) and Longyi 11 (Wei204 area). (2) Producing wells are drilled in priority in the surrounding areas of Weiyuan county with thick high-quality reservoir. (3) A medium to high intensity stimulation is adopted. After the implementation of these strategies, both the production rate and the estimated ultimate recovery (EUR) of individual shale gas wells have increased substantially.

New methodology approaches with a broad coverage of the biological effects are urgently needed to evaluate the safety of the universe of environmentally relevant chemicals. Here, we propose a tiered approach incorporating transcriptomics and in vitro bioassays to assess environmental mixtures. The mixture samples and the perturbed biological pathways are prioritized by concentration-dependent transcriptome (CDT) and then used to guide the selection of in vitro bioassays for toxicant identification. To evaluate omics' screening capability, we first applied a CDT technique to test mixture samples by HepG2 and MCF7 cells. The effect recoveries of large-volume solid-phase extraction on the overall bioactivity of the mixture were 48.9% in HepG2 and 58.3% in MCF7. The overall bioactivity potencies obtained by transcriptomics were positively correlated with the panel of 8 bioassays among 14 mixture samples combined with the previous data. Transcriptomics could predict their activation status (AUC = 0.783) and the relative potency (p < 0.05) of bioassays for four of the eight receptors (AhR, ER, AR, and Nrf2). Furthermore, the CDT identified other biological pathways perturbated by mixture samples, such as the pathway related to TP53, CAR, FXR, HIF, THRA, etc. Overall, this study demonstrates the potential of concentration-dependent omics for effect-based water quality assessment.

Short-chain chlorinated paraffins (SCCPs), a class of ubiquitous pollutants, are considered to be embryotoxic and teratogenic. However, little is known regarding the bioactivity and mechanisms at environmentally relevant concentrations at the embryonic period. Here, a concentration-dependent reduced transcriptomic approach was used to evaluate the environmental dose ( 60%) (p = 0.038), and the chlorine content of SCCP congeners affected the bioactivity associated with genotoxic pathways. The concentration-dependent reduced transcriptomic approach significantly improved the understanding of the ecological risk of environmental contaminants at early life stages.

Ground penetrating radar (GPR), as a newly nondestructive testing technology (NDT), has been adopted to explore the spatial position and the structure of the tree roots. Due to the complexity of soil distribution and the randomness of the root position in the natural environment, it is difficult to locate the root in the GPR B-Scan image. In this study, a novel method for root detection in the B-scan image by considering both multidirectional features and symmetry of hyperbola was proposed. Firstly, a mixed dataset B-Scan images were employed to train Faster RCNN (Regions with CNN features) to obtain the potential hyperbola region. Then, the peak area and its connected region were filtered from the four directional gradient graphs in the proposed region. The symmetry test was applied to segment the intersecting hyperbolas. Finally, two rounds of coordinate transformation and line detection based on Hough transform were employed for the hyperbola recognition and root radius and position estimation. To validate the effectiveness of this approach for tree root detection, a mixed dataset was made, including synthetic data from gprMax as well as field data collected from 35 ancient tree roots and fresh grapevine controlled experiments. From the results of hyperbola recognition as well as the estimation for the radius and position of the root, our method shows a significant effect in root detection.

Bisphenols (BPs) have the potential to interfere with the androgen receptor (AR). However, in silico screening and substitute design were difficult because little was known about the mechanisms by ...

Nitrite-dependent anaerobic methane oxidation (n-damo) process, mediated by Candidatus Methylomirabilis oxyfera of the candidate phylum NC10, was discovered recently which plays an important role in coupling the global nitrogen and carbon cycles. However, the distribution and diversity of this new anaerobic methane-oxidizing microorganism have not been investigated in desert lakes yet. The present study successfully retrieved n-damo bacterial 16S rRNA and pmoA gene sequences using PCR technique from lakes in Badain Jaran Desert of China. Phylogenetic analyses showed that n-damo bacteria widely occurred in brine and freshwater lakes on the desert with high diversity, including both sediment and water samples. The results of quantitative PCR indicated that the abundance of the 16S rRNA gene in lake sediments varied from 1.12 ± 0.68 × 105 to 1.64 ± 0.70 × 105 copies g−1 (dry weight), while that in water samples per milliliter was generally one order of magnitude lower than sediments. Correlation anal...

Acid mine drainage (AMD) is one of the most hazardous byproducts of some types of mining. However, research on how AMD affects the bacterial community structure of downstream riverine ecosystems and the distribution of metal resistance genes (MRGs) along pollution gradient is limited. Comprehensive geochemical and high-throughput next-generation sequencing analyses can be integrated to characterize spatial distributions and MRG profiles of sediment bacteria communities along the AMD-contaminated Hengshi River. We found that (1) diversities of bacterial communities significantly and gradually increased along the river with decreasing contamination, suggesting community composition reflected changes in geochemical conditions; (2) relative abundances of phyla Proteobacteria and genus Halomonas and Planococcaceae that function in metal reduction decreased along the AMD gradient; (3) low levels of sediment salinity, sulfate, aquatic lead (Pb), and cadmium (Cd) were negatively correlated with bacterial diversity despite pH was in a positive manner with diversity; and (4) arsenic (As) and copper (Cu) resistance genes corresponded to sediment concentrations of As and Cu, respectively. Altogether, our findings offer initial insight into the distribution patterns of sediment bacterial community structure, diversity and MRGs along a lotic ecosystem contaminated by AMD, and the factors that affect them.

Conventional ecological risk assessment on toxic stressors in sediment is limited to a small and selected fraction of benthic communities. Ecogenomic approaches provide unprecedented capacity to monitor the changes of biodiversity and community composition in the field, but how to utilize it to assess ecological impact by contaminates remains largely unexplored. Here, an environmental DNA (eDNA) metabarcoding approach was used to assess the effect of copper on changes in biodiversity and community composition across the tree of life (including bacteria, protists, algae, fungi, and metazoa) in a field-based microcosm. Many microorganisms across a broad range of taxa groups changed their relative abundance in response to increased copper concentrations in sediments. Changes in community structure of microbiota appeared to be more sensitive to copper than survival of laboratory-bred organisms and indigenous macroinvertebrates. Copper caused a significant shift in prokaryotic community composition via substitution of dominant species. Network heterogeneity and Shannon diversity of the bacterial community decreased in the high copper treatments. eDNA metabarcoding assessed the effects of copper-contaminated sediment with less effort than manually processing samples. Our study highlighted the value of community profiling by an eDNA-based approach in prospective and retrospective risk assessment of environmental stressors.

Freshwater ecosystems have been threatened by complicated disturbances from both natural and anthropogenic variables, especially in dynamic and complex river basins. The environmental DNA (eDNA)-based approach provides a broader spectrum and higher throughput way of biomonitoring for biodiversity assessment compared with traditional morphological survey. Most eDNA metabarcoding studies have been limited to a few specific taxa/groups and habitat scopes. Here we applied the eDNA metabarcoding to characterize the structures and spatial variations of zooplankton and fish communities among different habitat types in a highly dynamic and complex freshwater ecosystem of the Daqing River basin (DRB). The results showed that varied species spectra of zooplankton and fish communities were identified and unique dominant species occurred across habitats. Additionally, markedly spatial distributions of biotic community structures were observed in areas with different habitat characteristics. Natural variables, including geographic distances and gradient ratio, as well as anthropogenic factors of chemical oxygen demand (COD) and organic chemicals demonstrated significant effects but different outcomes on the structures of zooplankton and fish communities. Moreover, the relative abundances of specific aquatic taxa were associated with the gradient of particular environmental variables. This case study verified the distribution patterns and differentiation mechanisms of biotic communities under habitat heterogeneity could be captured by application of eDNA biomonitoring. And habitat-specific and even species-specific environmental stressors would be diagnosed for improving management of complex river basins.

Exposure to environmental chemicals, particularly those with persistent and bioaccumulative properties have been linked to liver diseases. Induction of fibrotic pathways is considered as a pre-requirement of chemical induced liver fibrosis. Here, we applied 3D in vitro human liver microtissues (MTs) composed of HepaRG, THP-1 and hTERT-HSC that express relevant hepatic pathways (bile acid, sterol, and xenobiotic metabolism) and can recapitulate key events of liver fibrosis (e.g. extracellular matrix-deposition). The liver MTs were exposed to a known profibrotic chemical, thioacetamide (TAA) and three representative environmental chemicals (TCDD, benzo [a] pyrene (BaP) and PCB126). Both TAA and BaP triggered fibrotic pathway related events such as hepatocellular damage (cytotoxicity and decreased albumin release), hepatic stellate cell activation (transcriptional upregulation of α-SMA and Col1α1) and extracellular matrix remodelling. TCDD or PCB126 at measured concentrations did not elicit these responses in the 3D liver MTs system, though they caused cytotoxicity in HepaRG monoculture at high concentrations. Reduced human transcriptome (RHT) analysis captured molecular responses involved in liver fibrosis when MTs were treated with TAA and BaP. The results suggest that 3D, multicellular, human liver microtissues represent an alternative, human-relevant, in vitro liver model for assessing fibrotic pathways induced by environmental chemicals.

Endocrine-disrupting chemicals (EDCs) can interact with nuclear receptors, including estrogen receptor α (ERα) and androgen receptor (AR), to affect the normal endocrine system function, causing severe symptoms. Limited studies queried the EDC mechanisms, focusing on limited chemicals or a set of structurally similar compounds. It remained uncertain how hundreds of diverse EDCs could bind to ERα and AR and cause distinct functional consequences. Here, we employed a series of computational methodologies to investigate the structural features of EDCs that bind to and activate ERα and AR based on more than 4000 compounds. We used molecular docking and molecular dynamics simulations to elucidate the functional consequences and validated structure-function correlations experimentally using a time-resolved fluorescence resonance energy-transfer assay. We found that EDCs share three levels of key fragments. Primary (20 for ERα and 18 for AR) and secondary fragments (38 for ERα and 29 for AR) are responsible for the binding to receptors, and tertiary fragments determine the activity type (agonist, antagonist, or mixed). In summary, our study provides a general mechanism for the EDC function. Discovering the three levels of key fragments may drive fast screening and evaluation of potential EDCs from large sets of commercially used synthetic compounds.

The ABCD conference format (All continents, Balanced gender, low Carbon transport, Diverse backgrounds) mixes live-streamed and pre-recorded talks with in-person ones to reflect a diverse range of viewpoints and reduce the environmental footprint of meetings while also lowering barriers to inclusiveness.

Aquatic ecosystems are monitored worldwide using a range of biological quality elements that are morphologically identified. The environmental DNA (eDNA)-based approach has unprecedented advantages (e.g., high throughput, high efficiency and low cost) for biodiversity surveys in both freshwater and marine ecosystems compared with traditional sampling and image recognition. The use of eDNA has been mostly limited to biodiversity estimation, how to apply the eDNA approach in assessing the ecological health status is largely unexplored. Here, using zooplankton as an example, we examined the application of eDNA monitoring for ecological status assessment in an aquatic ecosystem. The results showed that eDNA monitoring reflected the spatial and temporal variations in zooplankton structure. Both species composition and bio-interactions varied significantly between sampling seasons (dry, normal and wet). A total of 60 different zooplankton indices were calculated based on eDNA monitoring and most of these indices were highly correlated with the level of water pollution, which was indicated by the water quality index in one or all three seasons. Both qualitative and quantitative eDNA-based biological indices were correlated with water quality. The season-dependent eDNA zooplankton integrity index (IZI) reflected the ecological status, and this method improves the timeliness of bioassessment. Keywords: Mitochondrial cytochrome c oxidase I, Ecological assessment, High-throughput sequencing, DNA barcoding, Water quality, Zooplankton integrity

Increased synthetic chemical production and diversification in developing countries caused serious aquatic pollution worldwide with emerging organic pollutants (EOPs) detected in surface water rising health concerns to human and aquatic ecosystem even at low ng/L concentration with long-term exposure. The Yangtze River Delta (YRD) area serves agriculture and industry for people in eastern China. However, the current knowledge on the occurrence and ecological risk of diverse EOPs which are present in the aquatic environment is limited. This study was to investigate the complexity and diversity of EOPs in surface water from 28 sampling sites, which were selected to represent urban, industrial or agriculture areas in the YRD area. In total 484 chemicals were analyze by a target screening approach using liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-HRMS/MS). 181 out of 484 EOPs were detected at least one site in the YRD area, and 44 analytes, mostly industrial chemicals and pesticides, were ubiquitous at all sampling sites. Most EOPs were industrial chemicals with 1H-benzotriazole and organophosphate flame retardants (PFRs) as the chemicals with highest concentrations. For 21 pesticides, mostly herbicides, maximum concentrations of atrazine and isoproturon were above the annual average environmental quality standards of Europe. Amantadine and DEET were the dominant pharmceuticals and personal care products (PPCPs) in the YRD area. Compared to urban areas (mostly in Qinhuai River), chemical profiles from industrial areas were more complex. Industrial activities likely have a strong impact on the composition of chemical mixtures in surface water from the YRD area. ISO E Super, 4-methylbenzylidene camphor and clotrimazole detected in this study are potentially persistent and bioaccumulative chemicals. Furthermore, results of risk assessment showed that hazard quotients of dimethyldioctadecylammonium, didecyldimethylammonium and octocrylene were higher than one and occur frequently, which indicates possibly adverse effects on fish species in the YRD area.

Background Bioavailable phosphorus (BAP) represents the sum of phosphorus that is readily available for algae growth and is useful to indicate the severity of eutrophication in aquatic environments. Results Here, a quantitative real-time PCR (qPCR)-based bioassay was developed to quantify BAP using the indigenous cyanobacterium species Anabaena sp. of Lake Tai, a large and shallow eutrophic lake in the Yangtze Valley, China. Primers were designed to quantify the gene expression of alkaline phosphatase (phoA/phoA-like) and phosphate transporter (pst1) genes of Anabaena. The specificity and efficiency of the primer sets were evaluated by gel electrophoresis and real-time PCR. The results showed that the primers developed here could successfully be used to measure BAP in the water. The linear range of BAP measurements by the pst1 gene after 2 h incubation was 0.125–2.00 mg/L. Then, the qPCR-based bioassay was applied to analyze water samples from Tai Lake, which had BAP levels in the range of 0.239–0.459 mg/L. Conclusions The qPCR-based bioassay represents a promising biomonitoring tool that can quantify phosphorus bioavailability in aquatic environments.

Development of new approach methodologies is urgently needed to characterize the likelihood that complex mixtures of chemicals affect water quality. Omics advances in ecotoxicology allow assessment on a broadest coverage of disrupted biological pathway by mixtures. Here the usefulness of transcriptomic analyses for evaluation of combined effects and identification of main effect components are explored. Two artificial mixtures (Mix 1 and Mix 2) were tested by a concentration-dependent reduced zebrafish transcriptome (CRZT) approach and toxicity bioassays using zebrafish embryos. Then, the toxicities and transcriptomic effects of 12 component chemicals on embryos were incorporated into additivity models to characterize the combined effects of chemicals in mixtures and to identify the main bioactive compounds. Mix 1 and Mix 2 displayed similar embryo toxicities (LD50: 6.6 μM and 8.7 μM, respectively), however, Mix 2 elicited broader biological process perturbations and 5-fold higher transcriptome potency (point of departure eliciting a 20% pathway response, PODpath20) than Mix 1. The predicted mixture toxicities derived from additivity expectations deviated by 2-fold or less from the measured embryo toxicities except for the Jaw defect endpoint; most biological processes deviated by 3-fold or less. Finally, diclofenac (DFC) and propiconazole (PCZ) were identified as the main contributing components (≥80% explanation) to the embryo toxicity and biological process perturbations by Mix 1. While DFC and chlorophene (CLP) explained up to 80% of the embryo toxicities and biological effects of Mix 2 associated with development and Metabolism processes. The CRZT approach provides a powerful tool for assessment of biological pathways perturbed by chemicals in mixtures and for identification of main bioactive compounds.

Human-induced global change dramatically alters individual aspects of river biodiversity, such as taxonomic, phylogenetic or functional diversity, and is predicted to lead to losses of associated ecosystem functions. Understanding these losses and dependencies are critical to human well-being. Until now, however, most studies have only looked either at individual organismal groups or single functions, and little is known on the effect of human activities on multitrophic biodiversity and on ecosystem multifunctionality in riverine ecosystem. Here we profiled biodiversity from bacteria to invertebrates based on environmental DNA (hereafter, 'eDNA') samples across a major river catchment in China, and analysed their dependencies with multiple ecosystem functions, especially linked to C/N/P-cycling. Firstly, we found a spatial cross-taxon congruence pattern of communities' structure in the network of the Shaying river, which was related to strong environmental filtering due to human land use. Secondly, human land use explained the decline of multitrophic and multifaceted biodiversity and ecosystem functions, but increased functional redundancy in the riverine ecosystem. Thirdly, biodiversity and ecosystem function relationships at an integrative level showed a concave-up (non-saturating) shape. Finally, structural equation modeling suggested that land use affects ecosystem functions through biodiversity-mediated pathways, including biodiversity loss and altered community interdependence in multitrophic groups. Our study highlights the value of a complete and inclusive assessment of biodiversity and ecosystem functions for an integrated land-use management of riverine ecosystems.

With the increasing number of applications of silver nanoparticles (Ag NPs) in consumer products, including food contact applications, it is important to understand potential health effects of ingestion of Ag NPs. The biosafety analysis of Ag NPs in various mammalian cells has been widely studied; however, the influence of the gastrointestinal environment on the physicochemical properties and toxicity of Ag NPs has not been fully addressed. In the present study, we investigated the impact of simulated human gastrointestinal tract (GIT) fluids on the physicochemical properties of Ag NPs and their impact on the in vitro cytotoxicity of Ag NPs in intestinal epithelial (Caco-2) cells. Polyvinylpyrrolidone (PVP)-coated Ag NPs of different sizes (30, 50, 100 nm) were incubated in three GIT fluids that differed in composition and pH (1.6, 5.0, 6.5) and were designed to mimic human gastric fluid in a fasted state (FaSSGF), human intestinal fluid in a fasted state (FaSSIF), and human intestinal fluid in a fed state (FeSSIF). Time-dependent decreases in UV–Vis absorption and increases in dynamic light scattering (DLS) were observed during the three-hour incubation of Ag NPs in GIT fluids. The results of transmission electron microscopy (TEM) coupled with energy dispersive X-ray spectroscopy (EDS) suggested that the Ag NPs aggregated and precipitated as AgCl salts in the presence of FaSSGF and FeSSIF. In the presence of FaSSGF and hydrogen peroxide (H2O2), a particle size- and concentration-dependent generation of hydroxyl radicals ( OH) was detected by electron spin resonance (ESR) spectroscopy. When compared to the effects observed with the incubation of Ag NPs in H2O, incubation of Ag NPs in FaSSGF showed decreased cellular uptake in Caco-2 cells. In contrast, the incubation of Ag NPs in FeSSIF demonstrated increased cellular uptake and cytotoxicity. The results of this study demonstrate that GIT fluids have a significant influence on the physicochemical properties and cytotoxicity of Ag NPs and they provide valuable information that may be used in the safety evaluation of Ag NPs for consumer products.

A framework is presented that is intended to facilitate the evaluation of potential aquatic ecological risks resulting from discharges of down-the-drain chemicals. A scenario is presented using representatives of many of the types of chemicals that are treated domestically. Predicted environmental chemical concentrations are based on reported loading rates and routine removal rates for 3 types of treatment: trickling filter, activated sludge secondary treatment, and activated sludge plus advanced oxidation process as well as instream effluent dilution. In tier I, predicted effluent concentrations were compared with the lowest predicted-no-effect concentration (PNEC) obtained from the literature using safety factors as needed. A cumulative risk characterization ratio (cumRCR) 1.0 for all 3 treatment types in our scenario, even though no chemical exceeded a hazard quotient of 1.0 in activated sludge or advanced oxidation process. In tier 2, activated sludge yielded a lower cumRCR than trickling filter because of higher removal rates, and the cumRCR in the advanced oxidation process was <

Omics approaches can monitor responses of biological pathways at genome-scale, which are useful to predict potential adverse effects by environmental toxicants. However, high throughput application of transcriptomics in chemical assessment is limited due to the high cost and lack of matured dose response models. Here, a reduced zebrafish transcriptome (RZT) approach was developed to represent the whole transcriptome and to profile bioactivity of chemical and environmental mixtures in zebrafish embryo. Quantitative analysis of RZT gene expression by RNA-ampliseq technology was used to identify differentially expressed genes (DEGs) at 32 hpf following exposure to reference chemical, BPA, and four water samples ranging from wastewater to drinking water. Concentration-response modeling was used to calculate the effect concentrations (ECs) of DEGs and corresponding molecular pathways. RZT gene set of 1637 zebrafish Entrez genes was designed to cover a wide range of biological processes, and faithfully captured gene-level and pathway-level changes by toxicants compared with the whole transcriptome. The RZT-ampliseq-embryo approach was able to differentiate low dose response from a wide spectrum of biological activities for BPA. Finally, water quality was benchmarked based on the sensitivity distribution curve of biological pathways detected using RZT-ampliseq-embryo, and the most sensitive biological pathways were identified. RZT-ampliseq-embryo approach provides an efficient and cost-effective tool to derive pathway-based information of environmental toxicants.

Recently, great attention has been paid to the identification and prediction of the androgen disrupting potencies of polybrominated diphenyl ethers (PBDEs). However, few existing models can discriminate active and inactive compounds, which make the quantitative prediction process including the quantitative structure-activity relationship (QSAR) technique unreliable. In this study, different grouping methods were investigated and compared for qualitative identification, including molecular docking and molecular dynamics simulations (MD). The results showed that qualitative identification based on MD, which is lab-independent, accurate and closer to the real transcriptional activation process, could separate 90.5% of active and inactive chemicals and was preferred. The 3D-QSAR models built as the quantitative simulation method showed r2 and q2 values of 0.513 and 0.980, respectively. Together, a novel workflow combining qualitative identification and quantitative simulations was generated with processes including activeness discrimination and activity prediction. This workflow, for analyzing the antagonism of androgen receptor (AR) of PBDEs is not only allowing researchers to reduce their intense laboratory experiments but also assisting them in inspecting and adjusting their laboratory systems and results.

Sediment contamination is widespread and can be toxic to aquatic ecosystems and impair human health. Despite their significant ecological function, meio- and microbiota in aquatic ecosystems have been poorly studied in conventional sediment ecotoxicity tests because of the difficulty in sample collecting and identification. In the present study, a novel DNA metabarcoding method was used to assess the effects of spiked copper (Cu) on benthic eukaryotic and prokaryotic communities in laboratory sediment toxicity tests with macroinvertebrates, the chironomid Chironomus tepperi and the amphipod Austrochiltonia subtenuis. In addition to the obvious toxic effects to experimental animals, microbiota (bacteria, protists, algae, and fungi) were significantly altered by spiked Cu in the sediments. The phylogenetic diversity of eukaryotic communities was decreased after spiked-Cu exposure. Even a low-spiked Cu treatment (125 mg/kg) altered structures of eukaryotic and prokaryotic communities in the amphipod experiment. The present study demonstrates that measuring microbiota communities will expand our understanding of the influences of contaminants on aquatic ecosystems. Particularly, the alterations of phylogenetic biodiversity of eukaryotic communities and the structure of sedimentary communities are sensitive indicators for sediment contamination, which can be incorporated in the monitoring and assessment of sediment quality. Environ Toxicol Chem 2018;37:599-608. © 2017 SETAC.

Tight sandstones usually present great variations in Archie's exponents due to their high clay contents and multi-scale pores. Conventional multi-scale digital rocks consider the effect of micro and macro pores but ignore the contribution of clay minerals to electrical conductivity, whereas traditional multi-mineral digital rocks cannot consider the contribution of micro pores. We propose an upscaling method to construct complex digital rocks for accurate estimation of electrical conductivities. Based on a 3-D grayscale image of a tight sandstone acquired by X-ray CT and a 2-D mineralogy slice imaged by energy-dispersive SEM (EDS-SEM), we reconstruct a 3-D multi-mineral digital rock that is composed of intergranular pores and mineral phases by image registration and multi-threshold segmentation. Fine mineral structures and micro pores are revealed by the multi-scale imaging technique. The effective conductivity of each mineral phase associated with a specific micro porosity is calculated by the Archie's equation or Waxman-Smits model. By assigning each voxel with the optimal conductivity according to its mineral phase, we estimate the bulk electrical conductivity of the entire digital rock by the finite element method. The contributions of fluids and clay minerals to the bulk electrical properties are implicitly incorporated into the numerical simulation without increasing computational cost. The upscaling method is validated by experimental measurements of formation factors. We investigate the effect of clay minerals and scanning resolutions on the calculated electrical conductivities with attempt to interpret variations in the cementation exponent.

Batch experiments have been carried out to study the adsorption of heavy metals in soils, and the migration and transformation of hexavalent chromium (Cr(VI)) in the soil of a vegetable base were studied by dynamic adsorption and desorption soil column experiments. The aim of this study was to investigate the effect of initial concentration and pH value on the adsorption process of Cr(VI). Breakthrough curve were used to evaluate the capacity of Cr(VI) adsorption in soil columns. The results show that the higher the initial concentration, the worse the adsorption capacity of Cr(VI). The adsorption of Cr(VI) was strongly sensitive to pH value. The capacity of Cr(VI) adsorption is maximized at very low pH value. This may be due to changes in pH that cause a series of complex reactions in Cr(VI). In a strongly acidic environment, the reaction of Cr(VI) with hydrogen ions is accompanied by the formation of Cr3+, which reacts with the soil free iron-aluminum oxide to produce hydroxide in the soil. The results of the desorption experiments indicate that Cr(VI) is more likely to leach from this soil, but if the eluent is a strong acid solution, the leaching process will be slow and persistent. During the experiment, the pH value of the effluent was in the range of 7–8.5, which tends to the original pH value of the soil. It is indicating that the soil has a strong buffer on the acid liquid. The program CXTFIT was used to fit the breakthrough curve to estimate parameters. The results of the calculation of the dispersion coefficient (D) can be obtained by this program. The two-site model fit the breakthrough curve data of Cr(VI) well, and the parameters calculated by the CXTFIT can be used to explain the behavior of Cr(VI) migration and transformation in soil columns. When pH = 2, the retardation factor (R) reach at 79.71 while the value of the R is generally around 10 in other experiments. The partitioning coefficient β shows that more than half of the adsorption sites are instantaneous in this adsorption process and non-equilibrium affects the Cr(VI) transport process in this soil.

Functional gene fingerprinting of chemicals could be used to understand the direct gene-chemical interaction in the process of toxification from a genome-wide scale. 2, 2-bis (bromomethyl)-1, 3-propanediol (BMP) is a brominated flame retardant with widespread production but with very limited toxicological data. Here the cytotoxicity of BMP was assessed by Escherichia coli ( E. coli ) functional genome-wide knockout mutants screening and the underlying molecular mechanism was investigated. The median inhibition concentration (IC50) of BMP was 1.608 ± 0.078 mg/ml after 24 h exposure. 119 initial, including 66 sensitive and 53 resistant single gene mutants, were identified by a full library screening of BMP at the concentration of IC50. The resistant genes were significantly enriched in nucleobase-containing compound biosynthetic process (GO: 0034654) by gene ontology (GO) biological process analyses, which suggested that the pathway of DNA repair is a critical cellular process in the survival of cells exposed to BMP. Meanwhile, function annotation of all BMP responsive genes suggested the mechanism of BMP was associated with DNA damage, oxidative stress and cellular transmembrane transport process. Many genes were exclusively responsive to BMP comparing with other chemicals that has been assessed by E. coli mutant screening approach, which indicated that BMP has a distinct mode of toxic action. Overall, the functional genomic screening approach presented here provides a great tool to assess the cellular toxicological mechanism of environmental chemicals.

The scientific and appropriate tools and methods to evaluate location of coastal plant effluent discharge as a guideline for decision makers is indeed an urgent need to address the increasing threats of pollutant to coastal waters in China. With an industrial wastewater plant located near the Luoyuan Bay coastal area in Fujian of China as a case, the present study investigated the suitability of the whole sea area of Luoyuan Bay for the establishment of sewage outfall using the proposed index system and Multi-Criteria Decision-Making (MCDM) tool. Based on literature review, expert consultation and Analytical Hierarchy Process (AHP), an index system with two categories, 5 sub-categories and 9 indicators including index grading and weighting were constructed. With Weighted Suitability Analysis (WSA) and Grey Relation Analysis (GRA) employed here as two optional methods to evaluate the most suitable alternative, a complete and systemic site selection technology was put forward to support the marine environment management. The results showed that, of the 6 optional sites that in consist with law, local regulations and functional zoning, ranking of alternatives by WSA and GRA both indicated that the site of S5 obtained the highest priority. For the other 5 sites, there was a difference between the ranking results calculated by two methods. We then discussed the difference between WSA and GRA and proposed their applicable conditions from perspective of decision makers.

One of the major challenges in environmental science is monitoring and assessing the risk of complex environmental mixtures. In vitro bioassays with limited key toxicological end points have been shown to be suitable to evaluate mixtures of organic pollutants in wastewater and recycled water. Omics approaches such as transcriptomics can monitor biological effects at the genome scale. However, few studies have applied omics approach in the assessment of mixtures of organic micropollutants. Here, an omics approach was developed for profiling bioactivity of 10 water samples ranging from wastewater to drinking water in human cells by a reduced human transcriptome (RHT) approach and dose-response modeling. Transcriptional expression of 1200 selected genes were measured by an Ampliseq technology in two cell lines, HepG2 and MCF7, that were exposed to eight serial dilutions of each sample. Concentration-effect models were used to identify differentially expressed genes (DEGs) and to calculate effect concentrations (ECs) of DEGs, which could be ranked to investigate low dose response. Furthermore, molecular pathways disrupted by different samples were evaluated by Gene Ontology (GO) enrichment analysis. The ability of RHT for representing bioactivity utilizing both HepG2 and MCF7 was shown to be comparable to the results of previous in vitro bioassays. Finally, the relative potencies of the mixtures indicated by RHT analysis were consistent with the chemical profiles of the samples. RHT analysis with human cells provides an efficient and cost-effective approach to benchmarking mixture of micropollutants and may offer novel insight into the assessment of mixture toxicity in water.

Communities of zooplankton can be adversely affected by contamination resulting from human activities. Yet understanding the influence of water quality on zooplankton under field-conditions is hindered by traditional labor-intensive approaches that are prone to incomplete or uncertain taxonomic determinations. Here, for the first time, an eco-genomic approach, based on genetic diversity in the mitochondrial cytochrome c oxidase I (COI) region of DNA of zooplankton was used to develop a site-specific, water quality criterion (WQC) for ammonia (NH3). Ammonia has been recognized as a primary stressor in the catchment of the large, eutrophic Tai Lake, China. Nutrients, especially NH3 and nitrite (NO3–) had more significant effects on structure of the zooplankton community than did other environmental factors. Abundances of rotifers increased along a gradient of increasing concentrations of total ammonia nitrogen (TAN), while abundances of copepods and cladocera decreased. A novel, rapid, species sensitivity d...

Oil is a complex mixture of numerous compounds. Therefore, oil spills near shore can cause various adverse effects on coastal ecosystems. However, most toxicological assessments conducted on oil spill sites have focused on limited modes of toxic actions. In the present study, we utilized the Escherichia coli (E. coli) live cell array system (LCA) to identify novel modes of toxicities of the oil spill-affected sediments. For this purpose, sediment samples were collected from an area heavily polluted by Hebei Spirit oil spill (HSOS) incident of 2007. A total of 93 E. coli reporter genes were used to study responses to the chemicals in the mixture. E. coli K12 strains were exposed to extracts of oil or the sediment, and changes in gene expression were measured. Exposure to extracts of crude and weathered oil resulted in decreased expression in ∼30% of tested genes. However, changes in expression observed after exposure to sediment extracts varied. Sediment extracts containing large concentrations of polycyclic aromatic hydrocarbons (PAH) caused down-regulation of >70% of the genes, while extracts containing lesser total concentrations of PAHs exhibited different trends: genes involved in drug resistance were generally up-regulated, while genes responsive to DNA damage were up-regulated in only two extracts. Results suggest that oil pollution can modulate several toxic response pathways related to DNA repair and antibiotic responses. Results from LCA obtained from the sediment and oil samples were different from those observed in the H4IIE-luc assay. Toxicological implications of such observations deserve further examination. Overall, LCA is a promising tool for screening samples and identifying potential modes of toxicities of environmental samples associated with oil spills.

Evidence suggests that CO2 modifies the behavior of nanomaterials. Thus, in a few decades, plants might be exposed to additional stress if atmospheric levels of CO2 and the environmental burden of nanomaterials increase at the current pace. Here, we used a full-size free-air CO2 enrichment (FACE) system in farm fields to investigate the effect of elevated CO2 levels on phytotoxicity and microbial toxicity of nTiO2 (0, 50, and 200 mg kg− 1) in a paddy soil system. Results show that nTiO2 did not induce visible signs of toxicity in rice plants cultivated at the ambient CO2 level (370 μmol mol− 1), but under the high CO2 concentration (570 μmol mol− 1) nTiO2 significantly reduced rice biomass by 17.9% and 22.1% at 50 mg kg− 1 and 200 mg kg− 1, respectively, and grain yield by 20.8% and 44.1% at 50 mg kg− 1 and 200 mg kg− 1, respectively. In addition, at the high CO2 concentration, nTiO2 at 200 mg kg− 1 increased accumulation of Ca, Mg, Mn, P, Zn, and Ti by 22.5%, 16.8%, 29.1%, 7.4%, 15.7% and 8.6%, respectively, but reduced fat and total sugar by 11.2% and 25.5%, respectively, in grains. Such conditions also changed the functional composition of soil microbial communities, alerting specific phyla of bacteria and the diversity and richness of protista. Overall, this study suggests that increases in CO2 levels would modify the effects of nTiO2 on the nutritional quality of crops and function of soil microbial communities, with unknown implications for future economics and human health.

A large proportion of shale gas is in adsorbed state. However, in the process of shale gas development, adsorbed gas in the shale pores will gradually desorb, which results in the permeability change of shale. This study aims to find out the adsorption and desorption characteristics of shale and whether there exists certain impact of desorption effects on shale permeability by experiments. Isothermal adsorption and desorption curves of shale gas are not coincident and the desorption curves are in hysteresis. Langmuir equation can be used to calculate the shale isothermal adsorption curve and desorption equation can be used to calculate the shale gas isothermal desorption curve. The permeability of shale was measured, respectively, under low pressure and high pressure, with methane and helium as experimental gas. Then, the comparison was made between the results of shale and the similar experiment results of tight gas sandstone. The results are showed as follows: adsorption effects will break the linear relationship between the shale permeability and the reciprocal of average pore pressure under low pressure; under high pressure, when gas desorption enhances, shale permeability significantly increases. Therefore, adsorption effects can impact the shale permeability under low pressure as well as under high pressure, which should be taken into consideration in the shale gas development.

It is difficult to assess the toxicity of a single stressor and establish a strong stressor-causality link when multiple stressors coexist. Toxicity Identification Evaluation (TIE) methodology uses a series of chemical and physical manipulations to fractionate compounds within a matrix and systematically identify potential toxicants. The current EPA application of TIE can provide valuable information, but often lacks ecological realism and is subject to laboratory-related artifacts. An in situ TIE Device (iTIED) was designed to assess the sources of toxicity in aquatic ecosystems. For this laboratory validation, each unit was equipped with a sorbent resin chamber, an organism exposure chamber, a water collection container and a peristaltic pump. Chemical analyses of water processed by each iTIED unit were compared to both lethal and sub-lethal molecular responses of the organisms. The compound removal effectiveness of different sorbent resins was also compared. In addition to successfully fractionating diverse chemical mixtures, the iTIED demonstrated a potential for early detection of molecular biomarkers, which could identify chronic toxicity that may go unnoticed in traditional TIE assays. Utilizing this novel in situ system will reduce the uncertainty associated with lab-based simulations and aid management efforts in targeting compounds that pose the greatest threat. This article is protected by copyright. All rights reserved

The parameters of indoor environment inside the teaching building such as concentrations of carbon dioxide, air temperature and humidity are directly related to the learning efficiency and physical as well as psychological health of college students. The present study took the classroom on the campus as the research object, tested the thermal and humidity environment parameters, and analyzed the change tendency of these parameters with the time in a day. Then the thermal comfort conditions of classroom are evaluated and reasonable improvement suggestions are proposed.

Phthalate esters (PAEs) are known to be transferred to hands by contact with surfaces, however, little is known about the associations between masses on hand wipes and the frequency or duration of touching surfaces, especially surfaces in office environments. Relationships between PAEs on hands and multiple surfaces in offices were investigated. Wipes of hands, computers, and mobile phones as well as dust on furniture were collected from 55 offices in China. Positive associations were found between masses of di-2-ethylhexyl phthalate (DEHP), dibutyl phthalate (DnBP), benzyl butyl phthalate (BBP), and di-n-octyl phthalate (DnOP) on wipes of hands and wipes of keyboards of computers. When workers used keyboards with polymer covers (dust covers), masses of these lipophilic PAEs on hands were significantly correlated with masses on keyboards rather than dust on furniture. For workers who used keyboards without polymer covers, masses on hands were related to masses in dust on furniture. Use of polymer covers c...

Effects of chemical mixtures at environmentally relevant concentrations on endocrine systems of aquatic organisms are of concern. Triclocarban (TCC) and inorganic mercury (Hg2+) are ubiquitous in aquatic environments, and are known to interfere with endocrine pathways via different mechanisms of toxic action. However, effects of mixtures of the two pollutants on aquatic organisms and associated molecular mechanisms were unknown. This study examined effects of binary mixtures of TCC and Hg2+ on histopathological and biochemical alteration of reproductive organs in zebrafish (Danio rerio) after 21 d exposure. The results showed that: 1) At concentrations studied, TCC alone caused little effect on hepatic tissues, but it aggravated lesions in liver caused by Hg2+ via indirect mechanisms of disturbing homeostasis and altering concentrations of hormones; 2) Histological lesions were more severe in gonads of individuals, especially males, exposed to the binary mixture. Exposure to TCC alone (2.5 or 5 μg/L) (measured concentration 140 or 310 ng/L) or Hg2+ alone (5 μg/L or 10 μg/L (measured concentration 367 or 557 ng/L) slightly retarded development of oocytes, whereas co-exposure to nominal concentrations of 5 μg/L TCC and 10 μg /L Hg2+ promoted maturation of oocytes. In males, maturation of sperm was slightly delayed by exposure to either TCC or Hg2+, while their combinations caused testes to be smaller and sperm to be fewer compared with fish exposed to either of the contaminants individually; 3) Lesions observed in fish exposed to binary mixtures might be due to altered transcription of genes involved in steroidogenesis, such as cyp19a, 3beta-HSD, cyp17, 17beta-HSD and modulated concentrations of testosterone and estradiol in blood plasma. The observed results further support the complexity of toxic responses of fish exposed to lesser concentrations of binary chemical mixtures. Since it is impossible to collect empirical information in controlled studies of all possible combinations of toxicants, the application of omics methods might improve the predictive capabilities of results of single classes of chemicals.

Summary 1.Sediments accumulate chemicals that can be toxic to biota and often contribute to aquatic ecosystem decline. Measuring mortality in laboratory-bred organisms is a common way to assess sediment toxicity. However, mortality-based responses of resilient laboratory organisms may not reflect indigenous macroinvertebrate responses, which can be relatively more sensitive to sediment toxicants. A possible solution is to also measure responses at the sub-individual level. 2.Several organism responses to sediment copper toxicity were assessed in a field-based microcosm. Responses of laboratory-bred chironomids and snails deployed in microcosms were compared at sub-individual (metabolomic and gene expression), individual (survival and dry weight) and population (reproduction) levels, and contrasted to the abundance of colonizing macroinvertebrates in the microcosms. 3.Colonizing macroinvertebrate abundance showed a range of sensitivities based on EC50 (effect dose 50% change). Chironomidae made up 94.5% of the microcosm macroinvertebrates, with Paratanytarsus the most sensitive genus (EC50: 89 mg/kg copper) and Procladius the least sensitive (EC50: 681 mg/kg). 4.Survival of laboratory-bred organisms was the least sensitive response, comparable to decreased abundance of the least sensitive macroinvertebrate. Juvenile production in the snail, Potamopyrgus antipodarum, was the most sensitive population level response (EC50: 121 mg/kg), in contrast the snail Physella acuta was relatively more tolerant (EC50: 298 mg/kg). 5.Changes in sub-individual responses (gene expression and metabolite abundance) in laboratory-bred chironomid, Chironomus tepperi, were evident at 60 mg/kg. These changes likely reflect the direct effects of copper exposure and represent metal-specific responses. 6.Synthesis and applications. We showed that copper toxicity in sediments could be readily detected through changes in gene expression and metabolites in laboratory-bred chironomids exposed in field-based microcosms. These responses were more sensitive than mortality, and detected copper levels that caused microcosm chironomid populations to decline. These novel approaches will provide managers with new tools to better assess sediment toxicity. This article is protected by copyright. All rights reserved.

There is a wide concern that emerging organic pollutants (EOPs) in surface water could adversely affect human health and wildlife. However, the geographic distribution, exposure pattern and ecological risk of emerging organic pollutants are poorly understood at a global scale. This paper provides a comprehensive survey on the exposure level of EOPs in China, the US and the EU based on the published literature. The hazard level of three categories of EOPs, namely pharmaceuticals and personal care products (PPCPs), pesticides and industrial chemicals was further evaluated by adopting a novel Aquatic HazPi index that jointly accounts for the persistence, bioaccumulation, toxicity and bioactivity. Furthermore, a correlation analysis of land use with the surface water exposure status regarding the synthetic chemicals was conducted. According to the published data reported between 2010 and 2016, the concentration of pesticides in the US was higher than in the EU and China. The concentration of PPCPs in the EU was generally lower than in both the US and China, while the concentration of industrial chemicals in China was higher than in the EU and the US. Among the chemicals whose median concentration in surface water was >10 ng/L, the antiretroviral Efavirenz, the pesticide Fipronil, and octocrylene, an industrial chemical and cosmetic ingredient, were found with the highest aquatic HazPi value. Lastly, the spatial distribution and concentration of hazardous EOPs was shown to depend on local landscape and land usages. Our study provides the first broad overview on the geographic distribution, exposure pattern of hazardous EOPs in the three major economic entities: China, the US and the EU. Keywords: Chemical pollution, Risk assessment, Pesticide, Industry, Pharmaceutical and personal care products, Land use

As the largest semi-closed marine ecosystem in the world, the Black Sea has been heavily affected by human activities for a long time. Describing the biodiversity of multi-trophic biota in pelagic zone of the Black Sea and identifying the dominant environmental factors are prerequisites for protecting the sustainability of ecosystems. However, up to now, the taxonomic and distributional information about the Black Sea biota is not clear. Here, we employed a Tree-of-Life metabarcoding to analyze the biodiversity of eight communities in the Black Sea, investigated their biogeographical distribution, and further analyzed the influence of biological and abiotic factors on biota on large scales. We found that, (1) Over 8900 OTUs were detected in the Black Sea, of which 630 species were identified, covering the holistic biota from single-celled (bacteria 5620 OTUs 141 species; algae 1096 OTUs 185 species; protozoa 546 OTUs 146 species) to multicellular organisms (invertebrate metazoans 150 OTUs 34 species; fishes 1369 OTUs 76 species; large marine mammals 39 OTUs 5 species). (2) Higher trophic organisms (fishes and large mammals) distributed more evenly in space than the lower (microorganisms, protozoa and invertebrates). For lower trophic organisms, the vertical stratification was more obvious than the horizontal stratification (vertical p

Bisphenol A (BPA) is a typical endocrine disruptor. Bisphenol S (BPS) has been widely used as a substitute for various plastic materials due to the limited application of BPA. However, it does not mean that BPS is a safe substitute due to the lack of effective evaluation of BPS. In this study, the clinical model of Caenorhabditis elegans (C. elegans) was used to study the effects of BPS on the locomotion behavior, growth, reproduction, lifespan and antioxidant system. Our study found that C. elegans exposed to 0.01 μM BPS could have significantly inhibited locomotion behavior and growth, as well as damaged reproductive and antioxidant systems and lifespan. It is interesting to note that in multi-generational exposure studies, we found that BPS exhibits complex genotoxicity. With the transmission to the offspring, BPS showed more significant inhibition of the head thrashes of the nematode, while the effect on the body bends and body length was gradually weakened. The effect of BPS on the brood size shows different rules according to different concentrations and offsprings. Therefore, the safety of BPS still needs further evaluation, especially the multi-generational genotoxicity.

Aquatic ecosystems, such as rivers and lakes, are exposed to multiple stressors from anthropogenic activity and changes in climate, which have resulted in a general decrease in biodiversity, alteration of community structures, and can ultimately result in reduction of resources provided by natural ecosystems. Adverse outcomes caused by pollutants to ecosystems are determined not only by toxic properties but also ecological contexts of ecosystems, including indigenous biodiversity and community composition. It is therefore important to identify key factors, such as diversity of species and traits that determine the vulnerability of structures and functions of ecosystems in response to toxic substances. Detection and quantification of biodiversity and its activities using environmental DNA (eDNA) is arguably one of the most important technical advances in ecology in recent years. A huge opportunity has appeared to allow more relevant approaches for assessments of risks posed to ecosystems by toxic substances. eDNA approaches provide effective and efficient tools to evaluate the effects of chemical pollutants on (1) the occurrences and population of wildlife, (2) communities, and (3) the function of ecosystem in the field. Here a conceptual framework of adverse outcome pathways to relate molecular initiating events to apical ecosystem-level responses is proposed to connecting laboratory-based prediction to observations under field conditions. Particularly, future research opportunities on effects on biodiversity, community structure, and ecosystem function by toxic substances will be discussed.

Rice-crab (Chinese mitten crab, Eriocheir sinensis) coculture system has become one of the most important agricultural activities practiced in China. However, the effect of pesticide usage on the survival and edible safety of crab species living in the coculture system has not been investigated. In the present study, we created a field simulation experiment and discovered that the amount of pesticide chlorantraniliprole (CAP) entering the rice-crab coculture system accounted for 82.22% of the total CAP content present in the spray barrel. When CAP residues found in the soil leached into nearby areas, we observed an increase in the CAP concentration in the water and sediment. Specifically, peak CAP concentration (1.35 μg/L) was detected in water within 1 day, and a steady CAP concentration in the sediment (2.55 μg/kg) was detected within 3 days. Additionally, an extensive field sampling experiment conducted in the basin of the lower reaches of the Yangtze River revealed that CAP was routinely used in rice-crab coculture systems. Although detected CAP concentrations were below 1 μg/L in ditch water and below 1 μg/kg in ditch sediment, there was still a potential risk associated with the crab growth. Importantly, there was no risk associated with crab consumption, given the low detection frequency of CAP in the collected samples. Our analysis suggests that an increase in usage ratio and a decrease in the total CAP content will likely promote safe application of CAP in the rice-crab coculture systems.

The WUDAPT (World Urban Database and Access Portal Tools project goal is to capture consistent information on urban form and function for cities worldwide that can support urban weather, climate, hydrology and air quality modeling. These data are provided as urban canopy parameters (UCPs) as used by weather, climate and air quality models to simulate the effects of urban surfaces on the overlying atmosphere. Information is stored with different levels of detail (LOD). With higher LOD greater spatial precision is provided. At the lowest LOD, Local Climate Zones (LCZ) with nominal UCP ranges is provided (order 100 m or more). To describe the spatial heterogeneity present in cities with great specificity at different urban scales we introduce the Digital Synthetic City (DSC) tool to generate UCPs at any desired scale meeting the fit-for-purpose goal of WUDAPT. 3D building and road elements of entire city landscapes are simulated based on readily available data. Comparisons with real-world urban data are very encouraging. It is customized (C-DSC) to incorporate each city's unique building morphologies based on unique types, variations and spatial distribution of building typologies, architecture features, construction materials and distribution of green and pervious surfaces. The C-DSC uses crowdsourcing methods and sampling within city Testbeds from around the world. UCP data can be computed from synthetic images at selected grid sizes and stored such that the coded string provides UCP values for individual grid cells.

© 2019, The Author(s). The present monitoring and assessment of the chemical status of water bodies fail to characterize the likelihood that complex mixtures of chemicals affect water quality. The European Collaborative Project SOLUTIONS suggests that this likelihood can be estimated with effect-based methods (EBMs) complemented by chemical screening and/or impact modeling. These methods should be used to identify the causes of impacted water quality and to develop programs of measures to improve water quality. Along this line of reasoning, effect-based methods are recommended for Water Framework Directive (WFD) monitoring to cover the major modes of action in the universe of environmentally relevant chemicals so as to evaluate improvements of water quality upon implementing the measures. To this end, a minimum battery of bioassays has been recommended including short-term toxicity to algae, Daphnia and fish embryos complemented with in vitro and short-term in vivo tests on mode-of-action specific effects as proxies for long-term toxicity. The likelihood of adverse impacts can be established with effect-based trigger values, which differentiate good from poor water quality in close alignment with Environmental Quality Standards for individual chemicals, while taking into account mixture toxicity. The use of EBMs is suggested in the WFD as one avenue to establish the likelihood of adverse effects due to chemical pollution in European water systems. The present paper has been written as one component of a series of policy briefs to support decisions on water quality monitoring and management under the WFD.