The fate of antibiotic resistance genes in the coastal lagoon with multiple functional zones.

Coastal lagoons provide many important services to human society, but their year-round use for aquaculture introduces large amounts of sewage. The contamination of antibiotic resistance genes (ARGs) is therefore of great concern. In this study, 50 ARGs subtypes, two integrase genes (intl1, intl2), and 16S rRNA genes were detected by high-throughput quantitative PCR, and standard curves of all target genes were prepared for quantification. The occurrence and distribution of ARGs in a typical coastal lagoon (XinCun lagoon, China) were comprehensively explored. We detected 44 and 38 subtypes of ARGs in the water and sediment, respectively, and discuss the various factors influencing the fate of ARGs in the coastal lagoon. Macrolides-lincosamides-streptogramins B was the primary ARG type, and macB was the predominant subtype. Antibiotic efflux and antibiotic inactivation were the main ARG resistance mechanisms. The XinCun lagoon was divided into eight functional zones. The ARGs showed a distinct spatial distribution owing to the influence of microbial biomass and anthropogenic activity in different functional zones. Fishing rafts, abandoned fish ponds, the town sewage zone, and mangrove wetlands provided a large quantity of ARGs to the XinCun lagoon. Nutrients and heavy metals also significantly correlated with the fate of the ARGs, especially NO2--N and Cu, which cannot be ignored. It is noteworthy that lagoon-barrier systems coupled with persistent pollutant inputs result in coastal lagoons acting as a "buffer pool" for ARGs, which can then accumulate and threaten the offshore environment.

Emissions, Isomer-Specific Environmental Behavior, and Transformation of OBS from One Major Fluorochemical Manufacturing Facility in China.

Sodium p-perfluorous nonenoxybenzenesulfonate (OBS), a novel alternative to perfluorooctane sulfonic acid (PFOS), has been widely used in various fields in China and has certain toxic effects similar to PFOS. This study monitored OBS and 15 legacy PFASs in surface water, sediment, soil, and crucian carp near a fluorochemical manufacturing factory (FMF) in Suqian, China, focusing on the emission, isomer-specific environmental fate, and transformation of OBS. One to four orders of magnitude higher concentrations of OBS than other polyfluoroalkyl substances (PFASs) in all samples indicate that industrial emission is an important point source of OBS in the surrounding environment. The concentrations of OBS in surface water, sediment, and soil decreased exponentially as the distance from the FMF increases. The proportions of OBS-c, the dominant isomer, increased in the order: water (75.5 ± 6.4%), sediment (85.7 ± 10%), fish (muscle: 94.1 ± 0.99%; blood: 93.5 ± 1.4%), suggesting its preferential accumulation in sediment and fish than other isomers. Mono-hydroxylated transformation products of OBS were first identified in water, sediment, and fish, suggesting its hydroxylation may exist in the real environment. The transformation of OBS may explain its significantly lower bioaccumulation than PFOS in fish. However, considering the higher BAF of OBS than the regulatory bioaccumulation criterion and the possible stronger toxicity of its transformation products, further studies on its bioaccumulation and transformation are warranted.

Flux of Polynuclear Aromatic Compounds (PAHs) from the Atmosphere and from Reindeer/Bird Feces to Arctic Soils in Ny-Ålesund (Svalbard).

Atmospheric, soil, and feces samples were collected in Ny-Ålesund 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-Ålesund; the results showed flux values of ~ 0.07% from the initial PAH concentrations.

Spatial distribution of cumulative impact on terrestrial ecosystem of the Fildes Peninsula, Antarctica.

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.

Distribution and sources of polycyclic aromatic hydrocarbons in the water column of Kongsfjorden, Arctic.

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.

The ecotoxicological effects of microplastics on aquatic food web, from primary producer to human: A review.

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.

Preparation and application of a molecularly imprinted monolith for specific recognition of domoic acid.

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.

Distribution characteristics and indicator significance of Dechloranes in multi-matrices at Ny-Ålesund in the Arctic.

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.

Dynamic modeling of the occurrence, sources, and environmental behavior of polybrominated diphenyl ethers in Zhelin Bay, China.

This study analyzed polybrominated diphenyl ethers (PBDEs) in Zhelin Bay, China, investigating their occurrence, sources, and environmental behavior. PBDE congeners were detected in all sampled media. The Σ13PBDE concentrations in the dissolved phase ranged from 1.04 to 41.40 ng/L, while the concentrations ranged in suspended particulate matter from 0.02 to 12.56 ng/L. In sediments, PBDE concentrations ranged from 1.41 to 8.57 ng/g. The higher proportion of PBDEs in the dissolved phase in the bay than in the estuary is attributable to the type of PBDE products used in the aquacultural process in Zhelin Bay. Moreover, correlation analysis between PBDE concentrations and environmental parameters showed that the primary factor influencing PBDE concentrations in Zhelin Bay sediments may shift from riverine inputs to aquaculture. Principal component analysis and positive matrix factorization revealed that PBDEs in the water of Zhelin Bay primarily originated from the degradation of octa-BDE, deca-BDE, and penta-BDE products employed in aquaculture. In contrast, the PBDEs in Zhelin Bay sediments mainly originated from riverine inputs. In addition, a level IV dynamic fugacity-based multimedia model was used to simulate the temporal variation of PBDE concentrations in Zhelin Bay. Modeled short-term trends showed a relatively swift transport of PBDE congeners in the water column to the atmosphere and sediments. Over the long term, sediment concentrations gradually decreased, in contrast to the less rapid declines observed in the atmosphere and water. Furthermore, this study revealed that the transport and transformation processes of PBDEs in the Zhelin Bay environment were considerably influenced by the diffusion coefficient in water, the water-side mass transfer coefficient at the water-sediment interface, the sediment resuspension rate, and the organic carbon-water partition coefficient.

Occurrence, distribution, sources, and risk assessment of organophosphate esters in typical coastal aquaculture waters of China.

This study monitored 20 organophosphate esters (OPEs) in water and sediment from three typical mariculture bases (Yunxi Marine Ranching (YX), Hangzhou Bay (HZB), and Zhelin Bay (ZLB)) and Meiliang Bay (MLB) of Taihu Lake in China, focusing on the spatial distribution and sources of OPEs. Moreover, the occurrence and risk of OPEs in fishes from ZLB were evaluated. The ∑OPE concentrations in waters followed the order MLB (591 ng/L) > YX (102 ng/L) > HZB (70.0 ng/L) > ZLB (37.4 ng/L), with tri(1-chloro-2-propyl) phosphate (TCIPP), triethyl phosphate (TEP), and tri(2-chloroethyl) phosphate (TCEP) being the dominant OPEs. Significantly higher ∑OPE concentrations were found in sediment in MLB compared to the other three areas with similar levels. The decreasing concentrations of OPEs from nearshore to offshore areas in HZB and MLB indicated that terrigenous input is the main source of OPEs. The even distribution of OPEs in YX and ZLB combined with PCA analysis suggested ship traffic or aquaculture activities are also potential sources. The ∑OPE concentrations in fishes ranged from 0.551-2.45 ng/g wet weight, with TCIPP, tri-phenyl phosphate (TPHP), and TCEP being the main OPEs. Hydrophobicity was a key factor affecting the sediment-water distribution coefficients and the bioaccumulation factors of OPEs. The human exposure to OPEs through consumption of fishes from ZLB had a low health risk.

Occurrence and distribution of antibiotics and antibiotic resistance genes from the land to ocean in Daliao River-Liaodong Bay, China.

In this study, the pollution status of antibiotics and ARGs in sediments from the land-sea intersection of Liaodong Bay was analyzed. The results showed that the level of antibiotic pollution ranged from ND to 433.27 ng/kg, with quinolones and tetracycline as the dominant antibiotics. The relative abundance of ARGs ranged from 3.62 × 10-3 to 1.32 × 10-1 copies/16SrRNA copies, with aminoglycoside and MLSB resistance genes being dominant. Regarding spatial distribution, the land and estuary areas showed higher antibiotic pollution levels than the offshore areas. Similarly, the land and estuary areas exhibited higher antibiotic diversity than the offshore areas. The ARGs were widely distributed on land, and their abundance gradually decreased to the downstream estuary area. Land and coastal areas exhibited higher ARG diversity than estuary areas. Analysis of environmental factors revealed a significant correlation between ARGs and non-corresponding antibiotics, and some ARGs were affected by heavy metals Cu and Pb.

Trophic transfer of polycyclic aromatic hydrocarbons through the food web of the Fildes Peninsula, Antarctica.

The Antarctic ecosystem is characterized by few consumer species and simple trophic levels (TLs), rendering it an ideal setting to investigate the environmental behavior of contaminants. The paper aims to assess the presence, sources and biomagnification behavior of polycyclic aromatic hydrocarbons (PAHs) of the Antarctic food web and is the first study of biomagnifications of PAHs in the Fildes Peninsula in Antarctica. Nine representative species from the Fildes Peninsula in Antarctica were sampled and evaluated for PAH presence. PAH concentrations ranged from 477.41 to 1237.54 ng/g lipid weight (lw) in the sampled Antarctic biota, with low molecular weight PAHs (naphthalene, acenaphthylene, acenaphthene, and fluorene) comprising the majority of the PAHs. PAHs concentrations were negatively correlated with TLs. Further, the food web magnification factor (FWMF) of ∑PAHs was 0.63, suggesting biodilution of PAHs along the TLs. Source analyses revealed that the PAHs mainly originated from petroleum contamination and the combustion of fossil fuels.

The occurrence and abundance of antibiotic resistance genes in rivers of tropical islands: a case of Hainan Island, China.

In this study, the occurrence and distribution of 49 antibiotic resistance genes (ARGs) and two integrase genes (intl1, intl2) in three major rivers of Hainan Island, China, were investigated in July 2021, and to explore the spatial distribution of the target genes in the three rivers with the potential influencing factors such as regional characteristics and environmental factors. The results showed that a total of 46 ARGs and two integrase genes were detected in water and sediment, and the absolute abundance of ARGs ranged from 1.16 × 103 to 2.97 × 107 copies/L and 3.34 × 103-1.55 × 107 copies/g. ARGs of macrolides, aminoglycosides, and sulfonamides were this study's main types of ARGs. The aadA2, tetE, ermF, tetX, aac(6')-Ib, tetW, and qnrS genes are predominant ARGs in the water and sediment of the three rivers. The relative abundance of ARGs shows higher abundance in the midstream and downstream and lower abundance in the upstream and estuarine. After conducting a correlation analysis, it was found that there was a significant positive correlation between the ARGs detected in the water of the three main rivers. However, in sediment, tetC was negatively correlated with tetQ, macB was negatively correlated with ermF and ereA (p < 0.05), while the remaining ARGs showed positive correlations. Specifically, there was no significant positive correlation between tetQ and tetC, macB and ereA, and ermF in the sediments. Among the nine environmental factors studied, pH was found to be the main factor associated with the occurrence of ARGs in the aquatic environment, but it was also significantly associated with only nine ARGs. Among the detected heavy metals, only Cd and Zn showed significant correlations with the two ARGs in the water bodies of the three main rivers. It indicated that the pollution of ARGs in the three major rivers was in the initial stage, the detection abundance was low, the influence of environmental factors was small, and the interaction between ARGs seemed to be the main driving force. This study provides a scientific basis for further understanding the occurrence of ARGs and their influencing factors in a tropical island environment, and lays a foundation for subsequent management.

Occurrence, spatial patterns, air-seawater exchange, and atmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) from the Northwest Pacific to Arctic Ocean.

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/m3 and 34-338 ng/L, respectively. The air-seawater exchange flux of the region was calculated with a Whitman two-film model to be -82681-24613 ng/m2/day. Meanwhile, low-ring PAHs were transported from seawater to the air, while high-ring PAHs were transported from air to seawater. A correlation analysis between multiple environmental factors and particle phase ratio suggested that temperature might be the major driving factor for PAHs in the long-range atmospheric transport (LRAT) process. Moreover, the dry atmospheric deposition fluxes in the region were analyzed by considering environmental factors and the physicochemical properties of each PAHs monomer, these fluxes ranged from 0.001 to 696 ng/m2/day and were greater inshore than offshore and at higher latitudes. This study highlights that PAHs are affected by LRAT during their transport from Asia to Northwest Pacific and further to the Arctic Ocean, while emphasizing that air-seawater exchange plays an important role in air-sea interactions in the open ocean.

The reasons for the spatial and media distribution variations of ARGs in a typical semi-enclosed bay.

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 10-6 to 10-2, 10-6 to 10-3 and 10-5 to 10-2 copies/16S rRNA in coastal water, bay water, and sediments, respectively. The significant spatial variation of ARGs was explained by the fact that the coastal water was more susceptible to human activities, whereas environmental physicochemical factors played a crucial role in the bay water. The intrinsic reason for the media distribution variation was the different assembly processes in the two media, while the external reason was that the ARGs in the water and sediments were mainly influenced by environmental physicochemical factors and heavy metals, respectively.

Spatial distribution, source, and ecological risk of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in Jiaozhou Bay, China.

Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) are commonly found in the environment as components of brominated flame retardants. Due to their potential impact on human health and wildlife, it is imperative to closely monitor and manage their levels in the environment. This study investigated the spatial distribution, sources, and ecological risks of PBDEs and HBCDs in Jiaozhou Bay (JZB), a large bay situated on the eastern coast of China. The results showed that PBDE concentrations ranged from not detected (ND) to 7.93 ng/L in the water and ND to 65.76 ng/g in the sediment, while HBCD concentrations ranged from ND to 0.31 ng/L in the water and ND to 16.63 ng/g in the sediment. Furthermore, we observed significantly higher concentrations of PBDEs and HBCDs in the inner JZB compared to the outer JZB. Our source apportionment analysis showed that PBDEs primarily originated from the production and debromination of BDE-209, as well as the emission of commercial PeBDEs, whereas HBCDs in sediments mostly stemmed from anthropogenic activities and river input. Finally, our eco-logical risk assessment highlighted the need for continuous monitoring of PBDEs in JZB sediments. Overall, our study aims to provide valuable assistance for the environmental management of the JZB bay area, which is characterized by a complex net-work of rivers and a thriving economy.

Occurrence, source, and transfer fluxes of organophosphate esters in the South Pacific and Fildes Peninsula, Antarctic.

Concentrations of 11 organophosphate esters (OPEs) were investigated in surface water and atmosphere samples collected from the South Pacific and Fildes Peninsula. TEHP and TCEP were the dominant OPEs in South Pacific dissolved water, with concentration range of nd-106.13 ng/L and 1.06-28.97 ng/L, respectively. The total concentration of ∑10OPEs in the South Pacific atmosphere was higher than that in Fildes Peninsula, ranging from 216.78 to 2033.97 pg/m3 and 161.83 pg/m3, respectively. TCEP and TCPP were the most dominant OPEs in the South Pacific atmosphere, while TPhP was the most prevalent in the Fildes Peninsula. The air-water exchange flux of ∑10OPEs at the South Pacific was 0.04-3.56 ng/m2/day, with a transmission direction of evaporation totally determined by TiBP and TnBP. The atmospheric dry deposition dominated the transport direction of OPEs between air and water, with an flux of Σ10OPEs at 10.28-213.62 ng/m2/day (mean: 85.2 ng/m2/day). The current transport flux of OPEs through the Tasman Sea to the ACC (2.65 × 104 kg/day) was significantly higher than the dry deposition flux over the Tasman Sea(493.55 kg/day), indicating the Tasman Sea's importance as a transport pathway for OPEs from low latitude areas to the South Pacific. Principal component analysis and air mass back-trajectory analysis provided evidence of terrestrial inputs from human activities that have impacted the environment in the South Pacific and the Antarctic.

Determination of multiple organic flame retardants in maricultural water using High-volume/High-throughput Solid-phase extraction followed by liquid/gas chromatography tandem mass spectrometry.

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.

Distribution and characteristic of PAHs in snow of Fildes Peninsula.

Polycyclic aromatic hydrocarbons (PAHs) investigation in different matrices has been reported largely, whereas reports on snow samples were limited. Snow, as the main matrix in the polar region, has an important study meaning. PAHs in snow samples were analyzed to investigate the distribution and contamination status of them in the Antarctic, as well as to provide some references for global migration of PAHs. Snow samples collected in Fildes Peninsula were enriched and separated by solid-phase membrane disks and eluted by methylene dichloride, then quantified by gas chromatography/mass spectrometry. All types of PAHs were detected except for Benzo(a)pyrene. Principal component analysis method was applied to characterize them. Three factors (Naphthalene, Fluorene and Phenanthrene) accounted for 60.57%, 21.61% and 9.80%, respectively. The results showed that the major PAHs sources maybe the atmospheric transportation, and the combustion of fuel in Fildes Peninsula. The comparison of concentration and types of PAHs between accumulated snow and fresh snow showed that the main compound concentrations in accumulated snow samples were higher than those in fresh ones. The risk assessment indicated that the amount of PAHs in the snow samples would not lead to ecological risk.

A review of organophosphate esters in indoor dust, air, hand wipes and silicone wristbands: Implications for human exposure.

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.