Candidate biomarker discovery in plasma of juvenile cod (Gadus morhua) exposed to crude North Sea oil, alkyl phenols and polycyclic aromatic hydrocarbons (PAHs)

In this study we have investigated protein changes in plasma of juvenile Atlantic cod (Gadus morhua) induced by crude North Sea oil and North Sea oil spiked with alkyl phenols and polycyclic aromatic hydrocarbons, a surrogate produced water composition. Using a proteomic approach, we identified 137 differentially expressed proteins at different levels of crude oil exposure. Many of the induced protein changes occurred at low levels of exposure. The results obtained with protein expression profiles after exposure to oil and surrogate produced water indicate effects on fibrinolysis and the complement cascade, the immune system, fertility-linked proteins, bone resorption, fatty acid metabolism as well as increased oxidative stress, impaired cell mobility and increased levels of proteins associated with apoptosis. Although the number of individuals and samples in this study is limited within each treatment group, the protein changes observed in this study represent a first screening for potential biomarker candidates in cod plasma reflecting potential effects of crude oil and produced water exposure on fish.     

Effects of oil exposure on oxygen consumption of cod eggs and larvae

The oxygen consumption reflects the aerobic energy production of an animal. For fish eggs and larvae the normal oxygen consumption represents the optimal conditions for growth and development. Under the stress of environmental pollution gross deviation in oxygen uptake rate of the developing fish embryo may reflect metabolic disturbances and impede the development. Since the eggs and larvae of cod (Gadus morhua L.) are likely to be exposed to oil pollution from offshore installations in the North Sea we decided to investigate the effects of the water-soluble fraction (WSF) of North Sea crude oil on the oxygen consumption of cod eggs and larvae. The results showed that oxygen consumption of the larvae at the time of final yolk absorption (5–7 days post hatching at 5°C) is strongly suppressed by oil exposure at concentrations down to 50 ppb. No effect on the oxygen uptake, however, was found during the egg stage.     

High matrix interference affecting detection of PAH metabolites in bile of Atlantic hagfish (Myxine glutinosa) used for biomonitoring of deep-water oil production

The characteristic biology and wide distribution of hagfish species makes them relevant for use in pollution biomonitoring at great water depths, particularly in regions where deep-water oil production may take place. The exposure of fish to petrogenic contaminants can normally be detected from the level of polycyclic aromatic hydrocarbon (PAH) metabolites in bile fluid. Some of these metabolites are strong fluorophores, allowing analytical detection by means of simple fluorometric techniques such as fixed wavelength fluorescence (FF) and synchronous fluorescence scanning (SFS). In the present study bile from Atlantic hagfish (Myxine glutinosa) collected in pristine areas (Barents Sea and southwestern Norway) displayed strong bile fluorescence levels, suggesting the presence of PAH contaminants. However, gas-chromatography-mass spectrometry (GC-MS) analyses ruled out PAHs as the origin for this fluorescence signal. Rather, the bile of Myxine contains components resulting in unusually strong background fluorescence interfering at the wavelength pairs used for detection of PAH metabolites. Possible background for the observed matrix interference and implications for detection of PAH metabolites in hagfish is discussed.     

南黄海盆地北部坳陷北凹油气成藏特征的再认识

南黄海盆地北部坳陷北凹是一个大中型的中、新生代沉积凹陷,经过四十余年的油气勘探,至今仍无商业油气发现,仅发现诸城1-2一个含油气构造.北凹的油气勘探存在诸多问题,其中是否发育优质烃源岩、烃源岩能否生烃、油气是否运移至储层是关系到北凹油气勘探的基础地质问题.在对北凹主要烃源岩分析评价的基础上,采用流体包裹体系统分析技术,对北凹油气成藏特征展开研究.研究认为,北凹存在白垩系泰二段主力烃源岩,为中深湖相,生烃指标较好,分布面积较大,且现今已经成熟并排烃,生烃中心位于ZC-A井区.油气通过断裂发生垂向运移,已充注至始新统戴南组储层.流体包裹体荧光观察结果及显微测温结果均表明戴南组至少存在两期油充注,第一期发生在35 Ma左右,第二期为现今.     

Environmental risk assessment of alkylphenols from offshore produced water on fish reproduction

Concern has been raised over whether environmental release of alkylphenols (AP) in produced water (PW) discharges from the offshore oil industry could impose a risk to the reproduction of fish stocks in the North Sea. An environmental risk assessment (ERA) was performed to determine if environmental exposure to PW APs in North Sea fish populations is likely to be high enough to give effects on reproduction endpoints. The DREAM (Dose related Risk and Effect Assessment Model) software was used in the study and the inputs to the ERA model included PW discharge data, fate information of PW plumes, fish distribution information, as well as uptake and elimination information of PW APs. Toxicodynamic data from effect studies with Atlantic cod (Gadus morhua) exposed to APs were used to establish a conservative environmental risk threshold value for AP concentration in seawater. By using the DREAM software to 1) identify the areas of highest potential risk and 2) integrate fish movement and uptake/elimination rates of APs for the chosen areas we found that the environmental exposure of fish to APs from PW is most likely too low to affect reproduction in wild populations of fish in the North Sea. The implications related to risk management of offshore PW and uncertainties in the risk assessment performed are discussed.     

Declining Arctic Ocean oil and gas developments: Opportunities to improve governance and environmental pollution control

There has been global interest in the exploitation of rich hydrocarbon resources in the Arctic for decades. However, recent low oil prices, a low carbon economy climate agenda, and technical challenges of Arctic oil extraction have curbed interest in these Arctic resources. Despite a recent reluctance to explore and develop an offshore Arctic drilling industry, a resurgence in oil and gas prices could spark renewed interests that could pose unacceptable risks of pollution from oil spills. These risks are further compounded by complex governance and sovereignty issues between circumpolar nations. This paper (i) compares cycles of Arctic hydrocarbon exploration and exploitation activity with global energy prices; (ii) outlines current pollution abatement techniques under pan-Arctic national regulations to identify potential gaps; (iii) describes current international frameworks for Arctic governance to highlight how problems could arise if offshore oil drilling returns to the Arctic and associated spills migrate to international waters; and (iv) provides policy recommendations to aid both national and international policy-makers regarding pollution abatement methods for future Arctic drilling.     

Honey, I cooled the cods: Modelling the effect of temperature on the structure of Boreal/Arctic fish ecosystems

Historically colder regions of the North Atlantic had fisheries dominated by only a few fish species; principally cod and capelin. Possible population dynamic mechanisms that lead to such dominance are investigated by considering how a charmingly simple published multispecies model of the North Sea would react if the system operated at a lower temperature. The existing model equations were modified to describe temperature effects on growth, fecundity and recruitment and the model was rerun based on typical temperatures for the North Sea and a colder system. The results suggest that total fish biomass in the colder system increases but the community is more vulnerable to a given rate of fishing mortality. In the colder system, within species density dependence is reduced but relative predation rates are higher. Consequently, intermediate-sized species are vulnerable to relatively high levels of predation throughout their life history and tend to be excluded, leading to a system dominated by small and large species. The model helps to explain how temperature may govern coexistence and competitive exclusion in fish communities and accounts for the observed dominance of small and large species in Boreal/Arctic ecosystems.     

PAH in fish bile detected by fixed wavelength fluorescence

Fixed wavelength fluorescence (FF) for detection of polyaromatic hydrocarbon (PAH) metabolites in fish bile has been studied, and is presented through a laboratory and a field experiment. The method, which can be regarded as a biomarker of exposure to PAH, has proved to be a simple, rapid and cost effective method for monitoring PAH contamination.     

Aerospace methods and technologies for monitoring oil and gas areas and facilities

The urgency and specific features of the application of the up-to-date aerospace methods and technologies in order to monitor different oil and gas facilities; study subsurface geology of oil and gas areas; search for oil and gas deposits (particularly in Arctic regions); control oil, gas, and product pipelines; and estimate the environmental conditions in the areas of hydrocarbon production and transportation on land and on the sea are justified and analyzed. The problems in the oil and gas industry which can be solved using aerospace data are systematized. The principles of organization of aerospace monitoring and the physical bases of remote sensing methods for solving different problems in the oil and gas industry are considered. The application of aerospace methods and technologies in order to monitor the environmental conditions in the oil and gas production areas, monitor pipelines, detect pollution of the marine environment with oil products (particularly, after the accident on the oil platform in the Gulf of Mexico in 2010), and control the ice conditions in the Arctic oil and gas areas is illustrated.     

Relative importance of hydrocarbon pollutants, salinity and tidal height in colonization of oyster reefs

The relative effects of hydrocarbon pollutants, salinity and tidal height on the invertebrates and fish that inhabit oyster reefs were studied along the Louisiana Gulf of Mexico coastline. Dried oyster shell (cultch) was first exposed to crude oil in the laboratory. In a series of experiments, plastic trays filled with control and oil-exposed cultch were then deployed at two locations differing in salinity, in two seasons and at two tidal levels. In experiments on hydrocarbon, salinity, and seasonal effects, trays were colonized for one month. To examine the effects of colonization time, half of the trays were retrieved after two and the rest after five weeks. Salinity dramatically affected oyster reef assemblages, with species richness and total abundance halved at the estuarine site. Hydrocarbon effects were less prominent, whether cultch was dosed with light or heavy crude oil. The sub-tidal site had higher colonization rates, but colonization interval did not affect colonization, and seasonal differences occurred only at the higher-diversity, sub-tidal site. To determine effects of cleaners, Corexit 9580 was applied alone and with oil on cultch, and trays were colonized for one month. At high concentrations, the cleaner ameliorated hydrocarbon effects. In general, hydrocarbon effects were less prominent than salinity and aerial exposure in explaining colonization of oyster reef assemblages. Gas chromatography/mass spectrometry analysis of oyster shells after one month immersion revealed considerable losses of oil, especially with higher flow at the inter-tidal site. Sediment on shell also diluted oil. We argue that oyster reef assemblages should recover from small-scale spills, unless they occur during periods of reproduction and dispersal.     

白令海和楚科奇海鱼类种类组成及其对生态环境变化的响应

根据第4次中国北极科学考察在白令海与楚科奇海进行的鱼类拖网调查资料,分析了白令海与楚科奇海鱼类生物的种类组成、优势种、物种多样性和区系特征,探讨了鱼类生物对北极气候快速变化的响应。结果表明,白令海与楚科奇海两个海域共鉴定鱼类生物14科41种;主要优势种类为粗壮拟庸鲽(Hippoglossoides robustus)、北鳕(Boreogadus saida)、短角床杜父鱼(Myoxocephalus scorpius)、斑鳍北鳚(Lumpenus fabricii)、粗糙钩杜父鱼(Artediellus scaber);从适温性来看,冷水性种类最多,有35种,冷温性种类6种;从栖息地生态类型来看,底层鱼类、近底层鱼类和中上层鱼类分别为35、5和1种;Shannon-Wiener多样性指数平均为1.21,呈现南高北低的特点,整体多样性水平不高;气候变化引起部分北极、亚北极海区鱼类出现不同程度的纬向和纵向移动,由此将引起北极渔业资源分布格局的变化。     

Mixed-function oxygenases as biological monitors around petroleum hydrocarbon development sites: Potential for induction by diesel and other drilling mud base oils containing reduced levels of polycyclic aromatic hydrocarbons

The use of oil-based drilling muds has been discouraged in hydrocarbon exploration and production in the marine environment but these muds are presently being used to a considerable degree in the United Kingdom and Norwegian sectors of the North Sea. Field studies in the North Sea have demonstrated only localized impacts around individual drilling sites,^1,2 even including those sites where ‘toxic’ diesel oils were employed as base fluids in drilling muds. Yet the question of disposal of cuttings contaminated with oil from drilling muds remains somewhat controversial. The induction of mixed-function oxygenases (MFO) has been validated on a number of occasions in the field as a sensitive index of low level hydrocarbon exposure (reviewed by Payne),³ including sites in the North Sea where diesel-based muds were used.⁴ The present study demonstrates that any potential for induction by hydrocarbon contaminated cuttings will probably be reduced by substitution of low-aromatic base oils for diesel in drilling mud formulations.     

南黄海盆地海相中、古生界油气资源潜力研究

在对南黄海盆地海相中、古生界烃源条件和后期保存条件研究的基础上,运用盆地模拟手段并结合前人研究成果,对海相地层烃源岩的排烃史进行了模拟,计算了海相地层油气资源量,从而进行了海相油气资源潜力的分析;同时通过对海相上构造层和下构造层两套含油气系统成藏条件的研究,预测了盆地内海相油气资源的有利运聚区,进而指出南黄海盆地海相油气勘探的有利区,为下一步南黄海盆地的勘探部署提供了依据。研究表明,南黄海盆地海相下构造层和海相上构造层栖霞组、龙潭组—大隆组烃源岩推测为好的烃源岩,海相上构造层青龙组烃源岩推测为中等—好的烃源岩;盆地海相地层具有一定的油气资源潜力,油气资源总量为35.37×10^8t,且在纵向上,油气资源主要来自海相下构造层烃源岩系,在平面上主要分布于南部坳陷;盆地海相地层存在两类油气资源勘探有利区,其中,最有利区位于中部隆起区南部、南部坳陷区和勿南沙隆起区北部。     

Correlation between the level of the potential biomarker, heat-shock protein, and the occurrence of DNA damage in the dab, Limanda limanda: a field study in the North Sea and the English Channel

In the present study, heat-shock protein of M(r) 70 kDa (HSP70), a marker of cellular stress response, was validated as a potential biomarker under field conditions. The dab, Limanda limanda (female, size > or = 25 cm, spawning maturity stage 2) was used as the indicator organism. The data on HSP level were correlated with the occurrence of DNA damage, measured in the same specimens of L. limanda, to prove the usefulness of the method. The area under investigation was the North Sea. Four locations were selected: station N01, close to Heligoland, in the North Sea; station N04 at the Dogger Bank; station N06 at the Firth of Forth; and station G08 in the English Channel. Ten animals from each location were selected and their livers used for the experiments. The results show that the highest levels of HSP70 (consisting of two forms of M(r) 75 and 73 kDa) were in fish from station N04, while low values were measured in livers from L. limanda collected at station N01. Intermediate levels were seen in the animals from the two other locations. By application of a novel technique, it was found that the extent of DNA damage (single-strand breaks and alkaline labile sites) in fish liver parallels the levels of both HSP70 forms. Our results suggest that L. limanda may be a useful bioindicator and heat-shock proteins, a useful biomarker for monitoring of environmental pollution.     

南海北部陆缘盆地与坎坡斯盆地

我国南海是西太平洋最大的边缘海,其北部陆缘盆地深水区位于琼东南与珠江口盆地南侧.通过对该地区烃源条件、储层条件、圈闭条件及成藏模式等的初步研究,认为其具有良好的石油地质条件,有效勘探面积和勘探潜力巨大,具有良好的勘探前景.坎坡斯盆地位于巴西大西洋大陆边缘,是一个中生代到古新近纪含油气盆地,其内部的Garoupa, Carapeba, Namorado, Roncador, Marlim等深水油田的地质储量十分丰富,随着各个油田开发的深入,对该地区的深水含油气系统有了更加清晰的了解.本文通过两个地区在构造演化,烃源条件,储层条件,圈闭条件以及成藏模式的对比研究,对南海北部陆缘盆地深水区有了进一步的认识.     

Ethoxyresorufin-O-deethylase activity and fixed wavelength fluorescence detection of PAHs metabolites in bile in turbot (Scophthalmus maximus L.) Exposed to a dispersed topped crude oil in a Continuous Flow System

Long term effects of sublethal concentrations of oil on the marine environment have become of general concern. Cytochrome P4501A activity (EROD) in liver and fixed wavelength fluorescence detection of PAHs metabolites (FF) have in this study been used as biomarkers for dispersed oil exposure on a long term period of juvenile turbot (Scophthalmus maximus L.). A Continuous Flow System was used to carry out the study. The fish were continuously exposed to 0.125, 0.5 or 2.0 mg litre⁻¹ dispersed topped crude oil for 6, 15, 24 h, 4 and 21 days followed by a 9 days recovery period in clean seawater. No induction of the cytochrome P4501A was measured. A maximum level in bile metabolites (4- to 5-fold) was recorded after 24 h of exposure revealing thereby a detoxification process, but a decline occurred from day 4 to day 21. This study demonstrated that FF detection of PAHs metabolites in bile could be a more sensitive biomarker than EROD activity in a long term exposure to sublethal concentration of oil.     

In vivo formation of (+)-anti-benzo[a]pyrene diol-epoxide-plasma albumin adducts in fish.

Benzo[a]pyrene (BaP), a procarcinogenic polycyclic aromatic hydrocarbon (PAH), is bioactivated to BaP diol-epoxides (BPDEs) that can form adducts with DNA and blood proteins. We report here for the first time the in vivo formation of adducts between BPDE and plasma albumin (Alb) from two fish species experimentally exposed to BaP. Brook trout (Salvelinus fontinalis) received either a single i.p. dose (10 mg/kg) or two separate i.p. doses (25 mg/kg; 7 days apart) of BaP, and blood was collected 2 (single exposure) or 3 (multiple exposure) days post-treatment. Arctic charr (Salvelinus alpinus) received 10 i.p. doses (3 mg/kg; a single dose every 6 days), and blood was collected 2 days after the second, sixth, and 10th injections. BPDE-Alb adducts were measured by an improved HPLC/fluorescence method developed to detect and quantify BaP-tetrols released after acid hydrolysis of adducted Alb. HPLC/fluorescence chromatograms of Alb from BaP-treated fish revealed only BaP-tetrol I-1, thus indicating the formation of adducts exclusively via the (+)-anti-BPDE metabolite. Levels of (+)-anti-BPDE-Alb adduct ranged from 0.68 to 19.6 ng of tetrol I-1 per gram of Alb. Notably, adduct level was not related to BaP dose and there was no accumulation of adducts with repeated exposure, which may indicate a very short half-life (< 2 days) of plasma Alb in fish. The data suggest that BPDE-Alb adducts in fish could be useful as a non-destructive biomarker of recent exposure to bioactivated BaP.     

北极秋季海冰密集度与中国初冬降雨之间的关系

本文通过对中国地区实测降水及北极海冰卫星数据的分析,研究了北极秋季海冰密集度与中国初冬降雨的关系。合成分析的研究结果表明2000年之前中国南方和北方冬季降水偏少,中部降水偏多,这之后中国南方和北方冬季降水增加,中部降水减少。SVD研究结果显示,北极海冰减少使得近三十年来中国南方和北方冬季降雨呈现逐渐增多,中部地区(从青藏高原向东北方向至日本)降雨逐步减少的趋势。随着北极海冰的进一步减少,如遇合适的气候条件,南方冻雨出现的概率会加大。北极秋季海冰异常的回复过程加之冬季海冰异常的延续信号在中国、蒙古及日本北部激发一个阻塞高压,以巴伦支海/卡拉海为中心激发一个异常低压。这使得来自北冰洋大西洋扇区的冷空气南下至欧洲大陆和亚洲北部,在阻塞高压的影响下,冷空气进一步南下,进入东亚地区。这不仅使得亚洲冬季温度降低,也为中国北部降水增加提供条件。     

Composition of fish species in the Bering and Chukchi Seas and their responses to changes in the ecological environment

Based on trawl surveys in the Bering Sea and Chukchi Sea during the 2010 Chinese National Arctic Research Expedition, fish biodiversity characteristics, such as fish composition, dominant species, biodiversity, and faunal characteristics were conducted. We also discussed the responses of fishes to the quick changes in Arctic climate. The results showed that a total of 41 species in 14 families were recorded in these waters. The dominant species were Hippoglossoides robustus, Boreogadus saida, Myoxocephalus scorpius, Lumpenus fabricii, and Artediellus scaber. There were 35 coldwater species, accounting for 85.37%, and six cold temperate species, occupying 14.63%. The habitat types of fish could be grouped as follows: 35 species of demersal fishes, five benthopelagic fishes, and one pelagic fish. The Shannon–Wiener diversity index(H)(range between 0 and 2.18, 1.21 on average) was not high, and descended from south to north. Climate change has caused some fishes to shift along their latitudinal and longitudinal distribution around the Arctic and Subarctic areas, and this could lead to the decline of Arctic fishery resources.