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Numerous studies have elucidated the characteristics of polycyclic aromatic hydrocarbons (PAHs) in the Arctic; however, their behavior in different environments has not been studied at a large scale. To investigate the occurrence, spatial trends, air-seawater exchange and atmospheric deposition of 16 polycyclic aromatic hydrocarbons (PAHs), this study takes sample from the Northwest Pacific Ocean. to the Arctic Ocean.The concentrations of 16 PAHs in air and seawater ranged from 27 to 5658 pg/m

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Antibiotic resistance genes (ARGs) are considered a newly emerging contaminant. This study aimed to investigate the spatial and media distribution patterns of ARGs in Jiaozhou Bay, as well as the reasons behind these patterns. The results revealed that aminoglycoside and MLSB resistant genes predominated in all samples, and the relative abundance of ARGs ranging from 10

A rapid and efficient analytical method is proposed and optimized for the enrichment, extraction and instrument analysis of four typical organic flame retardants (OFRs), including organophosphate esters (OPEs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDs) and dechlorane compounds (Dechloranes) in maricultural waters using High-volume/High-throughput Solid-phase extraction with in-situ ultrasonic technique followed by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) and gas chromatography tandem mass spectrometry (GC-MS) instrumental detection. The optimized pretreatment conditions were that the analytes were enriched by XAD-2 resins and eluted repeatedly with 50 mL hexane/acetone (1:1, v:v) for 5 min. The results of method validation exhibited that the developed method can be used for quantitative detection of 11 OPEs, 13 PBDEs, 3 HBCDs and 5 Dechloranes in water samples. The method detection limits (MDLs) and limits of quantification (LOQs) are 0.4-26.2 pg/L and 1.5-87.4 pg/L for OPEs, 23.3-35.4 pg/L and 77.5-117.9 pg/L for HBCDs, 0.8-97.4 pg/L and 2.6-324.7 pg/L for PBDEs and 9.3-78.5 pg/L and 31.0-261.8 pg/L for Dechloranes, respectively. The method was successfully applied in lagoon maricultural areas in Hainan province, and the results showed that 4 OFRs were detected in almost all water samples. Total concentrations of 18 water samples were 1.89-39.97 ng/L for OPEs, 0.18-5.40 ng/L for PBDEs, ND-0.24 ng/L for HBCDs and 0.01-1.77 ng/L for Dechloranes, respectively. The optimized analytical method is highly sensitive and efficient with expectation to play an essential role in monitoring the ultra-trace organic pollutants and providing an effective risk assessment in ecological environment.

The prevalence of microplastics in global waters raises the concern about their potential effects on aquatic biota. In aquatic environment, microplastics are almost ubiquitously present in all compartments from surface water to benthic sediment, making them accessible to a wide range of aquatic biota occupying different habitats. Exposure to microplastics may induce detrimental implications to the health of aquatic organisms. This review describes the wide occurrence of microplastics ingestion by aquatic fauna and evaluates the ecotoxicological effects of microplastics as well as the associated chemicals on aquatic biota including phytoplankton and fauna from both freshwater and marine environments. Trophic transfer of microplastics and associated contaminants along the aquatic food chain and potential impacts on human health are also discussed. Finally, this review emphasizes the current knowledge gaps and gives recommendations for the future work.

Fifteen polycyclic aromatic hydrocarbons (PAHs) were detected in seawater and atmosphere of Bransfield Strait. The concentration of ∑15[PAH] in the atmosphere ranged from 3.75 to 8.53 ng m−3, and three-ring PAHs were the most abundant compounds. Dissolved ∑15[PAH] in seawater ranged from 5.42 to 34.37 ng L−1, and the level of PAHs was markedly different on each side of the strait. The air–sea gas exchange process and molecular diagnostic ratios were calculated, results showed that the environmental behavior of PAHs was net deposition along this cruise. Given the changes in global transport routes of pollutants under global warming, the role of long-range transport (LRT) may be enhanced. Taking the Antarctic as a sink of PAHs due to the LRT and net deposition, PAHs will continue to load into the seawater of this area via atmospheric deposition, which contributes to improving our understanding of the environmental behavior of PAHs.

Antibiotic Resistance Genes (ARGs) are considered to be emerging pollutants related to human activities. The rapid development of global urbanization has expanded human activities, thereby exacerbating the global human health risks caused by antibiotic resistance genes. The effects of urban and rural environments are multifarious, which makes the source and distribution of ARGs in the environment diversification. Understanding the distribution and spread of ARGs is essential for studying the environmental behavior of ARGs. In this study, the occurrence 296 genes were detected by the high-throughput qPCR technology, and FC value was used to analyze the diversity of ARGs and Mobile Genetic Elements (MGEs) in sediments between urban and rural areas of the Liaohe River Basin, China. The co-occurrence of MGEs and ARGs was analyzed using network to decipher core genes. A total of 187 ARGs and 10 MGEs were detected in all sediment samples. The average number of genes detected in urban sites is 89 higher than that in rural sites. The high abundance and various types of ARGs and MGEs detected in urban river sediments indicates that the occurrence of urban ARGs is more complex. MGEs were detected high levels and were significantly correlated with the abundance and diversity of ARGs in river sediments providing evidence that MGEs were related to the occurrence and distribution of ARGs and tnpA(tnpA-07, tnpA-01 and tnpA-03) gene were at the key position of co-occurrence of various types of ARGs.

The ubiquity of organophosphate esters (OPEs) in various environmental matrices inevitably pose human exposure risks. Numerous studies have investigated human exposure pathways to OPEs, including air inhalation, dust ingestion, dermal contact, and dietary and drinking water intake, and have indicated that indoor dust and indoor air routes are frequently the two main human exposure pathways. This article reviews the literature on OPE contamination in indoor air and dust from various microenvironments and on OPE particle size distributions and bioavailability in dust conducted over the past 10 years. Ways in which sampling strategies are related to the uncertainty of exposure assessment results and comparability among different studies in terms of sampling tools, sampling sites, and sample types are addressed. Also, the associations of OPEs in indoor dust/air with human biological samples were summarized. Studies on two emerging matrices, hand wipes and silicone wristbands, are demonstrated to be more comprehensive and accurate in reflecting personal human exposure to OPEs in microenvironments and are summarized. Given the direct application of some diester OPEs (di-OPEs) in numerous products, research on their existence in indoor dust and food and on their effects on human urine are also discussed. Finally, related research trends and avenues for future research are prospected.

Atmospheric, soil, and feces samples were collected in Ny-Alesund during July 2015. The concentrations, distributions, congener profiles, and contaminant migration levels were analyzed for 16 polycyclic aromatic hydrocarbons (PAHs) identified by the United States Environmental Protection Agency (US EPA) as priority contaminants (16 PAHs). Mean concentrations in the gas and particle phases were 37.8 ng m−3 and 2.9 ng m−3, respectively, and mean concentrations in soil and reindeer/bird feces were 329.1 ng g−1 and 720.7 ng g−1, respectively, on a dry weight (d.w.) basis. In more than three phases, naphthalene and phenanthrene dominated the concentrations of the 16 total PAHs (Σ16PAH) and the concentration of PAHs in the gas phase was much higher than in the particle phase. The main sources of local PAHs may be coal combustion and air-surface exchange. There was a volatilization tendency from soil to air for 2–4 ring PAHs, and exchange fluxes were ~ 105 times greater than the deposition fluxes of 5–6 ring PAHs. The underground migration of PAHs was investigated in Ny-Alesund; the results showed flux values of ~ 0.07% from the initial PAH concentrations.

Antarctica, an area that is devoted to global peace and research, is being challenged by climate change, human activities, and pollution. There have been a number of studies concerning the state of the Antarctic ecological environment. However, a comprehensive and quantitative assessment of the impact of threats on the Antarctica ecological environment is still lacking. In this study, a cumulative impact assessment performed on the basis of expert judgement was used to estimate species-specific differences on the impact of seven threats: climate change, organic and nonorganic pollutants, station construction, power generation, oil spilling, and tourism. The terrestrial area of the Fildes Peninsula was divided into 103 cells using a raster grid of 0.25 km2, and cumulative impact assessment was applied to each cell. The analysis results indicated that cumulative impact scores (IC) ranged from 0 to 39.4, and the cumulative scores were divided into six categories ranging from very low impact (IC ≤ 7.08) to very high impact (IC > 20.54). More than half of the terrestrial area (57.3%) experienced “Very Low Impact” or “Low impact” scores. For single factors, climate change was identified as a rapidly growing and significant threat facing the terrestrial ecosystems of Antarctica. In addition, tourism had the greatest impact among all human activities. The analytical process and resulting map indicate that it is necessary to develop international policies on the restriction of tourist activity space and strength the organic pollutant controls for terrestrial ecosystem protection in the Fildes Peninsula, Antarctica.

Quantifying the occurrence of Antarctic antibiotic-resistant bacteria (ARB) is essential for assessing the level of pollution and assessing the “baseline” or background level of ARB in human uninhabited environments. Animal feces, soil, and sediments were sampled from Fildes Peninsula. The abundance of sulfamethazine- and ciprofloxacin-resistance bacteria and antibotic resistance genes (ARGs) within ARB were investigated. The results showed Ciprofloxacin- and Sulfamethazine-resistant bacteria isolated from samples accounted for the highest abundances of 30 CFU/g and 79.8 CFU/g, respectively. The dominant genus of Sulfamethazine-and quinolone-resistance bacteria was Pseudomonas and Arthrobacter, respectively. 106 ARGs were detected from ARB. Strong positive correlations between mobile genetic elements (MGEs) and ARGs were found, what is relatively novel observation that the mechanism is confirmed to also occur in the Antarctic. This study reveals the compositional characteristics of ARGs of strains in Antarctic, providing support for the source of Antarctic antibiotic resistance and drug resistance mechanisms.

Antibiotic resistance is a worsening global concern, and the environmental behaviors and migration patterns of antibiotic resistance genes (ARGs) have attracted considerable interest. Understanding the long-range transport of ARG pollution is crucial. In this study, we characterized the dynamics of ARG changes after their release into aquatic environments and demonstrated the importance of traditional chemical contaminants in the transmission mechanisms of ARGs. We hypothesized that the main route of ARG proliferation switches from active transmission to passive transmission. This antibiotic-dominated switch is motivated and affected by non-corresponding contaminants. The effect of anthropogenic activities gradually weakens from inland aquatic environments to ocean environments; however, the effect of changes in environmental conditions is enhanced along this gradient. The insights discussed in this study will help to improve the understanding of the distribution and migration of ARG pollution in various aquatic environments, and provide a modern perspective to reveal the effect of corresponding contaminants and non-corresponding contaminants in the process of antibiotic resistance proliferation.

Understanding the antibiotic resistance transmission mechanisms and migration dynamics of antibiotic-resistant bacteria (ARB) in the natural environment is critical given the increasing prevalence of antibiotic resistance. The aim of this study was to examine the fate of sulfonamide-resistant fecal bacteria (E. coli) in an estuary ecosystem and to explore the role and contribution of environmental factors in this process. The prevalence of sulfonamide-resistance status of E. coli was analyzed over different seasons in two estuary systems. Environmental factors and disturbance indices of anthropogenic activities were evaluated by detecting antibiotic concentrations, heavy metal abundance and other physicochemical parameters. The abundances of antibiotic-resistant E. coli were significantly attenuated during land-sea migration suggesting that estuary environments play a natural mitigation role in the contamination of freshwaters by antibiotic-resistant E. coli. Additionally, environmental factors and disturbance indices of anthropogenic activities significantly correlated with the distribution and migration of antibiotic-resistant E. coli in the estuaries. Lastly, simulation experiments suggested differential adaptability between antibiotic-resistant and non-resistant E. coli towards environmental changes in estuary environments. Meanwhile, our results indicate that low concentrations of antibiotics will not increase the competitive advantage of resistant E. coli in estuaries.

The food web composition, assimilation efficiency of Dechlorane Plus (DP) in food web components, and even extrinsic conditions can affect the trophic biomagnification potentials of DP isomers in food webs. Antarctica ecological system is characterized by the presence of few consumers and simple trophic levels (TLs), which are crucial in discussing the behavior of contaminants. To assess the biomagnification potential of DP in the Antarctic food web, nine representative species were sampled and analyzed from the Fildes Peninsula. Results showed the DP concentrations ranged from 0.25 ng g− 1 to 6.81 ng g− 1 lipid weight in Antarctic biota and the concentrations of anti-DP and syn-DP showed significantly positive correlations with TLs (p

Spatial distribution, source apportionment, and potential ecological risks of sixteen polycyclic aromatic hydrocarbons (PAHs) and seven endocrine disrupting compounds (EDCs) in the intertidal sediment at the Shuangtaizi Estuary, Bohai Sea of China were analyzed. Results showed that the total PAH concentrations ranged from 28.79ngg-1 dw to 281.97ngg-1 dw (mean: 115.92ngg-1 dw) and the total EDC concentrations from 0.52ngg-1 dw to 126.73ngg-1 dw (mean: 37.49ngg-1 dw). The distribution pattern for the PAHs was generally different from that of the EDCs possibly due to their distinct sources and n-octanol-/water partition coefficients (KOW). Qualitative and quantitative analytical results showed that PAH sources were mainly from a mixture of pyrogenic and petrogenic contributions. The higher levels at the southeast of Geligang indicated that the EDC pollutants may have mainly originated from the plastic industry and other chemical plants located along the Liao River. Ecological risk assessment revealed that PAHs exhibited low ecotoxicological effects, whereas EDCs, especially 4-tert-octylphenol and bisphenol A, had high ecological hazard to the estuarine biota.

Long-term monitoring is essential for revealing pollution trends, but relevant studies in the Antarctic remain limited. In this study, a seven-year continuous monitoring of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere and soil was carried out at the Fildes Peninsula, Antarctica. Average concentrations of Σ15PAHs were 7134.491 pg/m3 and 61.093 ng/g in air and soil, respectively. A declining trend was observed for Σ15PAHs in air during the 2013–2019 summer, but this was not found in soil. Potential sources of PAHs in the Fildes Peninsula were identified by PMF modeling, correlation analysis, air mass back-trajectories and component analysis. The results showed that PAHs in the gas phase were more easily influenced by long-range atmospheric transport (LRAT) than in the particle phase. Moreover, temperature played a key role in the PAHs concentration in particle phase. Occurrence of Σ15PAHs in soil was mainly attributed to local sources including fossil fuel combustion and spilling.

Kongsfjorden is known for its characteristic multi-layer water mass formed by the convergence of freshwaters from nearby glaciers and rivers and saline water from the Atlantic and Arctic. The distribution of polycyclic aromatic hydrocarbons (PAHs) in the water column of Kongsfjorden was investigated and their potential sources were analyzed. The total concentrations of 16 PAHs in the surface seawater and river water were in the range of 33.4−79.8 ng/L (mean 48.5 ng/L) and 2.3−201.4 ng/L (mean 126.1 ng/L), respectively. Horizontally, PAHs were mainly concentrated around river estuaries and the glacier front in the dissolved phase. Vertically, the PAHs in the particulate phase followed surface-enrichment and depth-depletion patterns in most stations, with the maximum concentration found at 50 m depth in the central area of Kongsfjorden. The compositions of PAHs in seawater and rivers were similar, with two-ring and tricyclic PAHs comprising the majority of the dissolved and particulate phases. PAHs found in Kongsfjorden waters appeared to be derived from multiple sources such as petroleum and coal combustion. PAHs in the bay mouth of Kongsfjorden were mainly introduced by the West Spitsbergen Current and the Arctic waters, while in the inner bay, atmospheric deposition and local sources were the major contributors. The distribution of PAHs was mainly attributed to the suspended particulate distribution.

“Forecasting and Understanding Trends, Uncertainty and Responses of North Pacific Marine Ecosystems” (FUTURE) is the flagship integrative Scientific Program undertaken by the member nations and affiliates of the North Pacific Marine Science Organization (PICES). A principal goal of FUTURE is to develop a framework for investigating interactions across disciplinary dimensions in order to most effectively understand large-scale ecosystem changes and resulting impacts on coastal communities. These interactions are complex, often nonlinear, occur across a range of spatial and temporal scales, and can complicate management approaches to shared and trans-boundary problems. Here, we present a Social–Ecological–Environmental Systems (SEES) framework to coordinate and integrate marine science within PICES. We demonstrate the application of this framework by applying it to four “crisis” case studies: (a) species alternation in the western North Pacific; (b) ecosystem impacts of an extreme heat wave in the eastern North Pacific; (c) jellyfish blooms in the western North Pacific; and (d) Pacific basin-scale warming and species distributional shifts. Our approach fosters a common transdisciplinary language and knowledge base across diverse expertise, providing the basis for developing better integrated end-to-end models. PICES provides the structure required to address these and other multi-national, inter-disciplinary issues we face in the North Pacific. An effective and comprehensive SEES approach is broadly applicable to understanding and maintaining resilient marine ecosystems within a changing climate.

Antibiotic resistance pollution is globalizing. However, little quantitative data exists regarding the occurrence of antibiotic resistance genes (ARGs) in Antarctica, which is central to assessing the level of global contamination of ARGs. Soil, sediment, and animal feces were sampled from 12 sites in the Fildes Peninsula in January and February 2017. The occurrence and distribution of qnrS, sul1 and sul2 were investigated. The results showed that sul1 was the predominant ARG and that all the ARGs were detected in animal feces. The total absolute abundance of the ARGs in animal feces (5.86 × 107 copies) was the highest. Strong and positive correlations between sul1 and int1 were found, indicating that int1 might play an important role in the creation and spread of ARGs. This data and the analysis are critical for filling the data gap regarding ARGs in Antarctica and for improving understanding of the globalization of antibiotic resistance pollution.

The occurrence and estrogenic activities of seven phenolic endocrine-disrupting chemical (EDC) compounds (nonylphenol (NP), octylphenol (4-OP), 2,4-dichlorophenol (2,4-DCP), 4-tertbutylphenol (4-t-BP), 4-tert-octylphenol (4-t-OP), tetrabromobisphenol A (TBBPA), and bisphenol A (BPA)) in the sediments of Qingduizi Bay (NorthernYellow Sea, China) in superficial sediments were investigated to evaluate their potential ecological impacts on the health of aquaculture organisms. All compounds, except 4-OP and 4-t-BP, were recorded in most sampling sites (1.06–28.07 ng g−1 dw in maricultural ponds (MPs), 1.98–8.22 ng g−1 dw in outer bay (OB)). BPA and 4-t-OP were the predominant EDC compounds in MPs and OB, respectively. Correlation between BPA and 4-t-OP indicated these compounds may share a similar source or pathway. Analyzed estrogenic activity revealed a low risk of total EDCs. The ranking of risk quotient showed 4-t-OP posed a median risk and TBBPA posed a high risk to the aquatic ecosystem.

The sink-source controversy for global polycyclic aromatic hydrocarbons (PAHs) in high-latitude seas is extremely concerning. A level III fugacity model was developed for the southern Chukchi Sea to estimate the fate of 16 priority PAHs. The model results indicate large losses were due to seawater advection outflow, followed by degradation in seawater. The Chukchi Sea serves as a source of 4 PAHs (i.e., Nap, Ace, Acp and Fl) in the atmosphere and sediment but acts as a final sink for the other 12 PAHs. The water-air diffusion flux and wet deposition flux play dominant roles in the total transfer flux of the 4 PAHs and the other 12 PAHs, respectively. The source/sink role that high-latitude seas play in PAH distribution has changed under the influence of global climate change. The model proposed in this study provides an approach to support further study of the fate of PAHs in high-latitude seas.

This study developed a method to perform the simultaneous concentration and selective separation of 66 (ultra) trace persistent toxic substances in Antarctic waters. The substances included 30 polychlorinated biphenyls, 17 organochlorine pesticides, 16 polycyclic aromatic hydrocarbons, 3 hexabromocyclododecanes. Solid phase extraction was performed using a C 18 membrane and silica gel column. Gradient elution was conducted using organic solvents with different polarities; as a result, the efficiency of the C 18 film is improved and the interferences from impurities and target compounds are eliminated. Extracts were subsequently analyzed through gas chromatography or liquid and gas chromatography coupled to tandem mass spectrometry. Method validation yielded the following values: recoveries of all target analytes in the Antarctic water ranged from 87.3% to 117.6% and reproducibility as percent relative standard deviation was lower than 5%. Quantification limits ranged from 0.004 μg L −1 to 0.030 μg L −1 . The established method improved the recoveries and reduced the limits of detection. Results indicated the method exhibited good performance in the simultaneous concentration and selective separation of 66 (ultra) trace organic pollutants; Therefore, the proposed sample pretreatment can potentially eliminate the effects of various classes of impurities to some extent.

Eleven organophosphate esters (OPEs) in air and seawater were investigated from the Northwestern Pacific to the Arctic Ocean. The concentration of Σ11OPEs in air and seawater ranged from 231.56 to 1884.25 pg/m3 and from 8.47 to 143.45 ng/L, respectively. Halogenated OPEs dominated in both two media. The slight decreasing trend was observed for OPEs in gaseous air, no obvious trend for particle-bound OPEs and in seawater. The net air-seawater exchange flux ranged from −792.68 to 590.29 pg/m2/day. The dry deposition flux ranged from 16.4 to 185 ng/m2/day with high value observed at the Bering Strait (64.70 ng/m2/day). The relationship between temperature and OPEs particle-bound fractions suggests that temperature might be a driving factor of OPEs long-range atmospheric transport (LRAT). This research highlighted that OPEs are subject to LRAT from the Asian continent to the northwestern Pacific and Arctic Oceans and demonstrated the “sink” in polar regions of OPEs atmospheric transportation.

Dechloranes (Decs) have been widely found in the environment, even in the Tibetan Plateau and remote polar regions. However, the understanding of their regional distribution characteristics in polar regions is limited. To study the long-range atmospheric transport and fates of these emerging contaminants, Decs were analyzed in soil and lichen from the Fildes Peninsula in Antarctica. The concentrations of five Decs in soil and lichen ranged from 141.46 to 838.47 pg/g dw and 237.04 to 3599.18 pg/g dw, respectively. The mean fractions of anti-Dechlorane Plus (DP) (fanti) values estimated in the current soils (0.37) and lichen (0.24) were lower than those of commercial products (fanti = 0.64&ndash, 0.80), which confirms that long-range atmospheric transport is a main source of DP, and the DP burdens could be driven by the accumulation of syn-DP. The average &Sigma, DP concentration in soil in the coastal area was higher than that in the inland area and Ardley Island, while in lichen, the average DP concentration at the Ardley Island site was approximately three-fold higher than that in the coastal area and inland areas. This indicates that the distribution of DP was influenced by anthropogenic interference and animal activities in the Fildes Peninsula. The spatial variation of fanti of the three regions was clearer in soil than that in lichen. The fanti values were negatively correlated with DP concentrations in soil, suggesting that DP concentration levels play an important role in determining the isomeric composition of DP in the soil.

The concentrations and congener-specific profiles of polybrominated diphenyl ethers (PBDEs) were investigated in the atmosphere, soil and moss samples were collected from Ny–Alesund, Svalbard in the Arctic and King Georgia Island (KGI), Fildes Peninsula in Antarctica, respectively. The congener profiles of PBDEs were symmetrical between gas and moss, as well as between particles and soil at Ny–Alesund and KGI, respectively, similar to a “mirror image”. The proportions of highly brominated congeners (for example, BDE–99, –153 and –183) in the particle phase and soil were higher than those in the gas phase and moss, while tri– and tetra–BDEs possessed higher proportions in the gas phase and moss at both sites. The slopes of log–log linear correlations between the gas–particle partition coefficient (Kp) and sub–cooled liquid vapor pressures (p°L) of PBDEs were observed at both sites compared with the values in the urban areas. Moreover, the slopes of logKp vs. logp°L (−0.51 at Ny–Alesund and − 0.29 at KGI) were notably close to the slopes of log–log linear correlations between the dimensionless soil–moss quotient (QSM) and p°L (−0.42 at Ny–Alesund and −0.22 at KGI). Significant correlations between particle fraction (φparticle) and soil fraction (φsoil) at both sites indicated that the gas–particle partitioning of PBDEs is directly related to their distribution in moss and soil.

The occurrence and fate of antibiotics in biological wastewater treatment facilities have given rise to significant concerns. This study assessed the effects of fluoroquinolones (FQs), one class of representative antibiotics in wastewater, on the performance and the bacterial community of an anoxic–aerobic membrane bioreactor operated for one year. Results show that addition of FQs to feed wastewater caused significant increases of chemical oxygen demand (COD) in the mixed liquor. Nitrogen species in permeate increased slightly after the addition of FQs but then decreased to steady levels after long-term adaptation. However, phosphorous removal was consistently poor after FQs addition. 16S rRNA gene-targeted 454-pyrosequencing revealed a sharp decrease in the microbial species richness after FQs addition and significant fluctuations of bacterial community structure at both phylum and genus levels. Members of the two dominant phyla (Proteobacteria and Bacteroidetes) appeared to be well-adapted to the FQs. Moreover, changes in relative abundance of genera (e.g., Nitrospira, Dechloromonas, Acidovorax and Opitutus) involved in nitrogen cycling were in agreement with the reactor performance of nitrification and denitrification. Clone library analysis of the amoA gene further revealed a drastic shift of dominant ammonia-oxidizing bacteria (AOB) from the Nitrosomonas communis lineage (before FQs addition) to the Nitrosomonas oligotropha lineage (after FQs addition). Batch tests on the nutrient removal and FQs biodegradation further supported the changes in microbial community structure. This study provides a much-needed look at the bacterial community dynamics in activated sludge bioreactors for the treatment of antibiotics-containing wastewater.

The ubiquity and photoreactivity of fluoroquinolone antibiotics (FQs) in surface waters urge new insights into their aqueous photochemical behavior. This study concerns the photochemistry of 6 FQs: ciprofloxacin, danofloxacin, levofloxacin, sarafloxacin, difloxacin and enrofloxacin. Methods were developed to calculate their solar direct photodegradation half-lives (td,E) and hydroxyl-radical oxidation half-lives (tOH,E) in sunlit surface waters. The td,E values range from 0.56 min to 28.8 min at 45° N latitude, whereas tOH,E ranges from 3.24h to 33.6h, suggesting that most FQs tend to undergo fast direct photolysis rather than hydroxyl-radical oxidation in surface waters. However, a case study for levofloxacin and sarafloxacin indicated that the hydroxyl-radical oxidation induced risky photochlorination and resulted in multi-degradation pathways, such as piperazinyl hydroxylation and clearage. Changes in the antibacterial activity of FQs caused by photodegradation in various waters were further examined using Escherichia coli, and it was found that the activity evolution depended on primary photodegradation pathways and products. Primary intermediates with intact FQ nuclei retained significant antibacterial activity. These results are important for assessing the fate and risk of FQs in surface waters.

In recent years, Dechloranes have been widely detected in the environment around the world. However, understanding and knowledge of Dechloranes in remote regions, such as the Arctic, remain lacking. Therefore, the concentrations of 5 Dechloranes in surface seawater, sediment, soil, moss, and dung collected from Ny-Ålesund in the Arctic were measured with the concentrations 93 pg/L, 342, 325, 1.4, and 258 pg/g, respectively, which were much lower than those in Asian and European regions. The mean ratios of anti-Dechlorane Plus (DP) to total DP (ƒanti) in seawater, sediment, soil, moss, dung, and atmospheric samples were 0.36, 0.21, 0.18, 0.27, 0.66, and 0.43, respectively. Results suggested that the main source of DP in seawater, sediment, soil, and moss was long-range atmospheric transport. However, the ratio identified in dung was different, for which the migration behavior of the organism is probably the main source of DP.

Polychlorinated Biphenyls (PCBs) were analyzed in multi-environmental samples collected from Ny-Ålesund, the Arctic to explore their legacy and transfer patterns. PCBs were ubiquitously in the environmental media, within the ranges of 1.73-6.27 and 9.18-141.1 pg m(-3) in vapor and aerosol, 2.76-10.8, 3.09-8.32, 22.5-56.3, 35.4-51.4 and 31.8-39.6 ng g(-1) (dry weight) in soil, sediment, plant, bird guano and reindeer faeces, respectively. The spatial distribution patterns exhibited a general southward decline in soil and sediment from the bay entrance to the inner bay. The concentration ratios of plants to soil inferred that no distinguished selective adsorption of PCBs congeners by plants existed and PCBs were mainly attributed to the air deposition on plant surface. The fugacity ratios among vapor, aerosol and soil indicted that the equilibrium status has not been reached and the net transferring direction was air-soil.

The environmental behaviors and migration patterns of antibiotic resistance genes (ARGs) have attracted considerable research interest. However, there has been little research concerning the effects of corresponding and non-corresponding contaminants on the fate of ARGs in coastal environments. In the present study, the distribution of intI1, sul1, sul2, qnrS and aac(6')-Ib were analyzed in water and sediment samples of Laizhou Bay in the context of corresponding and non-corresponding contaminants. The abundance of intI1, sul1 and sul2 genes exhibited a clear decreasing trend extending from the inner estuary to the coastal area. Strong and positive correlations existed between sul1/sul2 and sulfonamide antibiotic residues in sediments, and between the abundances of intI1 and sul1/sul2. Statistical analyses indicated that non-corresponding contaminants were partially correlated with ARG abundances. These results suggest that non-corresponding contaminants may have direct or indirect influences on the abundances of ARGs and intI1 in the Laizhou Bay.

In this work, a molecularly imprinted monolithic column was synthesized by a facile procedure and was applied for specific recognition of domoic acid, an amnesic shellfish poison. The poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) molecularly imprinted monolith was synthesized in a stainless steel column by in situ polymerization. Pentane-1,3,5-tricarboxylic acid was used as a dummy imprinting template instead of the highly toxic and expensive target molecule. It is the first time that a molecularly imprinted monolith is introduced for separation and detection of domoic acid. After optimizing the preparation conditions, the prepared imprinted monolith was systematically characterized and exhibited excellent stability and permeability as a HPLC stationary phase. The results of chromatographic analysis demonstrated that the molecularly imprinted monolith exhibited specific retention and selective recognition toward domoic acid, with an imprinted factor up to 3.77. Furthermore, the molecularly imprinted monolith was successfully applied for selective enrichment of domoic acid from biological samples. Graphical abstract A molecularly imprinted monolith was prepared by using a dummy imprinted template and was successfully applied for specific recognition of domoic acid.

Adverse outcome pathways (AOPs) are a novel concept that effectively considers the toxic modes of action and guides the ecological risk assessment of chemicals. To better use toxicity data including biochemical or molecular responses and mechanistic data, we further developed a species sensitivity-weighted distribution (SSWD) method for bisphenol A and 4-nonylphenol. Their aquatic predicted-no-effect concentrations (PNECs) were derived using the log-normal statistical extrapolation method. We calculated aquatic PNECs of bisphenol A and 4-nonylphenol with values of 4.01 and 0.721 µg/L, respectively. The ecological risk of each chemical in different aquatic environments near Tianjin, China, a coastal municipality along the Bohai Sea, was characterized by hazard quotient and probabilistic risk quotient assessment techniques. Hazard quotients of 7.02 and 5.99 at 2 municipal sewage sites using all of the endpoints were observed for 4-nonylphenol, which indicated high ecological risks posed by 4-nonylphenol to aquatic organisms, especially endocrine-disrupting effects. Moreover, a high ecological risk of 4-nonylphenol was indicated based on the probabilistic risk quotient method. The present results show that combining the SSWD method and the AOP concept could better protect aquatic organisms from adverse effects such as endocrine disruption and could decrease uncertainty in ecological risk assessment. Environ Toxicol Chem 2018;37:551-562. © 2017 SETAC.

Polychlorinated biphenyls (PCBs) were measured in atmospheric samples collected from the North Pacific to the Arctic Ocean between July and September 2012 to study the atmospheric concentration characteristics of PCBs and their gas/particle partitioning. The mean concentration of 26 PCBs (vapor plus particulate phase) (ΣPCBs) was 19.116 pg/m3 with a standard deviation of 13.833 pg/m3. Three most abundant congeners were CB-28, −52 and −77, accounting for 43.0% to ΣPCBs. The predominance of vapor PCBs (79.0% to ΣPCBs) in the atmosphere was observed. ΣPCBs were negative correlated with the latitudes and inverse of the absolute temperature (1/T). The significant correlation for most congeners was also observed between the logarithm of gas/particle partition coefficient (logK P) and 1/T. Shallower slopes (from −0.15 to −0.46, average −0.27) were measured from the regression of the logarithm of sub-cooled liquid vapor pressures (logp L ○ ) and logK P for all samples. The difference of the slopes and intercepts among samples was insignificant (p>0.1), implying adsorption and/or absorption processes and the aerosol composition did not differ significantly among different samples. By comparing three models, the J-P adsorption model, the octanol/air partition coefficient (K OA) based model and the soot-air model, the gas/particle partitioning of PCBs in the Arctic atmosphere was simulated more precisely by the soot-air model, and the adsorption onto elemental carbon is more sensitive than the absorption into organic matters of aerosols, especially for low-chlorinated PCB congeners.

Polycyclic aromatic hydrocarbons (PAHs) were detected in water and sediment samples collected from three mariculture zones in China's northern Yellow Sea. In these samples, total PAH concentrations ranged from 110.8 ng/L to 997.2 ng/L and 142.2 ng/gdry weight (dw) to 750.2 ng/gdw, respectively. The log KOC values of the various PAH compounds examined in this study increased with the log KOW values, which is consistent with the prediction regarding PAH behavior in the environment. However, these KOC values were lower than the predicted values as a result of the effects of organic matters, which were abundant in the mariculture water. The isomeric ratios of the PAHs in sediment indicated that the source of the PAHs in the mariculture zones were mainly pyrolytic. The TEQ(carc) values of PAHs ranged from 7 ng TEQ/gdw to 92 ng TEQ/gdw, and only a few samples met the safe criterion with respect to individual PAH concentrations.

Chlorinated paraffins (CPs) were measured in air samples at a remote air monitoring site established in Georgia King Island, Fildes Peninsula of Antarctica (Great Wall Station, China) to study the long-range atmospheric transport of these anthropogenic pollutants to the Antarctic. Gas- and particle-phase CPs were collected using polyurethane foam plugs (PUF) and glass fiber filters (GFF) respectively during summertime of 2012. The total atmospheric levels of SCCPs and MCCPs ranged from 9.6 to 20.8 pg m−3 (average: 14.9 pg m−3) and 3.7–5.2 pg m−3 (average: 4.5 pg m−3), respectively. C10 and C11 carbon chain homologues with Cl5 and Cl6 chlorine atoms predominated in SCCP formula groups both in gas- and particle-phase. Significant linear correlation was found between gas/particle partition coefficients (KP) and sub-cooled liquid vapor pressures (pL°) (R2 = 0.437, p < 0.01), as well as KP and octanol–air partition coefficients (KOA) (R2 = 0.442, p < 0.01). Absolute slope values of two regression models (0.31 and 0.39) were less than 0.6 indicating that the way of absorption into organic matter of aerosol played a more important role on atmospheric partitioning and transferring of CPs in remote Antarctic area. Both the Junge–Pankow model and the KOA-based model tended to underestimate the sorption of lower chlorinated CPs and overestimate the sorption of highly chlorinated CPs.

Gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs) were collected in the atmosphere from the North Pacific to the Arctic Ocean to investigate their occurrence and gas/particle distribution. Significant linear correlations were observed between the gaseous concentrations of 9 PAHs and latitudes (r2 = 0.69). The regression of gaseous PAHs and 1/T also gave a certain extent correlation (r2 = 0.46). The gas/particle partition coefficients (KP) correlated well with the sub-cooled liquid vapor pressures (poL) of PAHs with slopes higher than the theoretical value of −1, and the regressions of logKP–logpoL possessed a general tendency to intersect at a point (−2.52, −1.60). The non-linear regression of logpoL and the particle fraction displayed a more significant correlation (r2 = 0.84) than the linear relation of logKP–logpoL (r2 = 0.69). The influence of soot on KP was investigated, and it was found that the predicted values derived from the soot-air model agreed relatively better with the field measurements than those calculated based on the Junge–Pankow model and the KOA-based model. The results indicated that soot played an important role on the partitioning of PAHs to aerosols, and the partitioning of PAHs is more sensitive to presence of elemental carbon compared to organic matter of the aerosol.

The effects of extraction solvent, capillary column, cleanup method, co-eluted analytes and other influencing factors on the detection of kepone in seawater were investigated. The analytical method of gas chromatography (GC) coupled with electron capture detector (ECD) was established to determine kepone in seawater. In the method, liquid-liquid extraction and sulfuric acid cleanup were used in the sample pre-processing. Chromatographic analysis was performed on a DB-5 capillary column with external standard method. The kepone was extracted from a 1 L seawater sample by 50 mL dichloromethane. Sulfuric acid was used to remove the interference materials co-extracted from the sample. After cleanup, the extract was dissolved in 1% (v/v) methanol/hexane solvent and analyzed by GC-ECD. In the linear range from 5 microg/L to 100 microg/L of kepone, the correlation coefficient was 0.998 9. The average spiked recoveries were 81% - 108% with the relative standard deviations (RSDs) of 1.2% -5.1% (n = 6). The detection limit was 0.6 ng/L. This method shows good extraction efficiency, high sensitivity and good reproducibility, and is suitable for the determination of kepone in seawater.

Pollution status of 16 polycyclic aromatic hydrocarbons (PAHs) was investigated in coastal water of Bohai Sea, China, and ecological risks of the 4 typical PAHs (naphthalene, phenanthrene, fluoranthene, and benzo(a)pyrene) were assessed using probabilistic risk assessment approach. The average concentration of total 16 PAHs was 3504 ng/L, and 3- and 4-ring PAHs were the dominant species. The probabilistic risks of the four typical PAHs were calculated using probability density function curve and joint probability distribution curve. The maximum acceptable ecological risks of 95% of the species being unaffected for the 4 compounds were 0.004, 0.035, 0.135, and 0.010, respectively. The joint ecological risk of the four PAHs was higher than the summation of their individual ecological risks, revealing that the summation of the calculated ecological risk of PAH mixtures underestimated their integrated ecological risks when they co-existed in aquatic environment.

To examine the bacterial community structure in the Fildes Peninsula, King George Island, Antarctica, we examined the bacterial diversity and community composition of samples collected from lacustrine sediment, marine sediment, penguin ornithogenic sediments, and soils using culture-dependent and culture-independent methods. The 70 strains fell into five groups: Actinobacteria, Bacteroidetes, Firmicutes, Gammaproteobacteria, and Betaproteobacteria. Bacterial diversity at the phylum level detected in Denaturing Gradient Gel Electrophoresis (DGGE) profiles comprised Proteobacteria (including the subphyla Alpha-, Beta-, Gamma-, Deltaproteobacteria), Bacteroidetes, Firmicutes, Chlorobi, and Deinococcus-Thermus. Gammaproteobacteria was identified to be the dominant bacterial subphylum by cultivation and DGGE method. By cluster analysis, the overall structure and composition of bacterial communities in the soil and lacustrine sediment were similar to one another but significantly different from bacterial communities in penguin ornithogenic sediment and marine sediment, which were similar to one another. The majority of 16S rDNA sequences from cultured bacteria were closely related to sequences found in cold environments. In contrast, a minority of 16S rDNA sequences from the DGGE approach were closely related to sequences found in cold environments.