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Sediment cores from Staten Island's salt marsh contain multiple historical oil spill events that impact ecological health. Microtox solid phase bioassay indicated moderate to high toxicity. Multiple spikes of TPH (6524 to 9586 mg/kg) and Σ16 PAH (15.5 to 18.9 mg/kg) were co-incident with known oil spills. A high TPH background of 400–700 mg/kg was attributed to diffuse sources. Depth-profiled metals Cu (1243 mg/kg), Zn (1814 mg/kg), Pb (1140 mg/kg), Ni (109 mg/kg), Hg (7 mg/kg), Cd 15 (mg/kg) exceeded sediment quality guidelines confirming adverse biological effects. Changes in Pb206/207 suggested three metal contaminant sources and diatom assemblages responded to two contamination events. Organic and metal contamination in Saw Mill Creek Marsh may harm sensitive biota, we recommend caution in the management of the 20–50 cm sediment interval because disturbance could lead to remobilisation of pre-existing legacy contamination into the waterway.

We present a new method for deriving surface soil gas flux at the field scale, which is less fieldwork intensive than traditional chamber techniques and less expensive than those derived from airborne or space surveys. The “open-field” technique uses aspects of chamber and micrometeorological methods combined with a mobile platform and GPS to rapidly derive soil gas fluxes at the field scale. There are several assumptions in using this method, which will be most accurate under stable atmospheric conditions with little horizontal wind flow. Results show that soil gas fluxes, when averaged across a field site, are highly comparable between the open-field method and traditional chamber acquisition techniques. Atmospheric dilution is found to reduce the range of flux values under the open-field method, when compared to chamber-derived results at the field scale. Under ideal atmospheric conditions it may be possible to use the open-field method to derive soil gas flux at an individual point; however this requires further investigation. The open-field method for deriving soil–atmosphere gas exchange at the field scale could be useful for a number of applications including quantification of leakage from CO2 geological storage sites, diffuse degassing in volcanic and geothermal areas, and greenhouse gas emissions, particularly when combined with traditional techniques.

Large-scale compressed air energy storage facilities offer one solution to the UK9s energy demands, using solution-mined caverns in salt lithologies. For optimum gas storage efficiency, cavern geometry should ideally be smooth: spherical to cylindrical with a circular cross-section. However, such caverns are often irregular with marked asymmetry or ellipticity, and although the reasons for non-circular cross-sections developing during solution mining in some caverns can be related to, for example, the presence of interbedded lithologies, in other instances they are not fully understood. Cavities from dissolution experiments using five main end-member salt facies fabrics from the Triassic Preesall and Northwich Halite formations have been assessed to determine factors affecting cavity geometry, formation and variability in dissolution behaviour. Identical sets of experiments were performed on each fabric type, using two solution concentration strengths: brine and synthetic seawater. Comparison of experimental results using a combination of analytical and imaging techniques shows the extent to which the salt fabric and enhancement of features within the salt influence the resulting dissolution cavity. Observations show a visible increase in micropores within the adjacent halite matrix following dissolution. Smaller-scale features provide further insights into the dissolution processes, and salt fabric behaviour under different dissolution conditions. Supplementary material: A detailed description of methods is available at https://doi.org/10.6084/m9.figshare.c.4282454

BGS 102, a guidance material for bioaccessible arsenic (As) and lead (Pb), was produced during validation of the in vitro Unified Bioaccessibility Method (UBM). This paper reports a compilation of reproducible bioaccessible guidance values for fifty-five additional elements in BGS 102, providing guidance for analysts to broaden the scope of UBM analyses for a wider range of elements based on data collected over an average of 60 separate analytical batches per element. Data are presented in categories for both gastric (STOM) and gastrointestinal (STOM + INT) extraction phases, where reproducibility, measured as relative standard deviation (RSD) was; ≤ 10% RSD for 27 elements (Mg, Al, Si, P, Ca, Cr, Mn, Co, Ni, As, Rb, Sr, Y, Ba, La, Ce, Pr, Nd, Sm, Eu, Tb, Gd, Dy, Ho, Er, Tm, Yb); between 10 and 20% RSD for 10 elements (Li, K, V, Fe, Cu, Zn, Cd, Lu, Pb, U); and ≥ 20% RSD for 19 elements in the gastric phase (Be, B, S, Ti, Ga, Se, Zr, Nb, Mo, Ag, Sn, Sb, Cs, Hf, Ta, W, Tl, Bi, Th). Two elements (Mg, Rb) met the ≤ 10% RSD criteria in the UBM gastrointestinal extraction phase due to the alkaline conditions of this phase precipitating out the majority of determinands. Certain elements, including Na, K, Zn and Se, were found to be a significant component of the extraction fluids with proportionally higher concentrations compared to the guidance material. Bioaccessible fractions (%BAF) were also calculated, but were found to be a less reproducible format for confirming the accuracy of measurements. The low concentration of some elements of interest in BGS 102, such as antimony (Sb), justifies the preparation of an alternative certified reference material (CRM). This paper presents an opportunity to broaden the scope of the UBM method to address food security issues (e.g. Fe and Zn micronutrient deficiencies) and contributions to dietary intake from extraneous dust or soil through evidence of the analytical possibilities and current limitations requiring further investigation.

Sites of natural CO2 leakage provide opportunities to study the potential environmental impacts of such leakage on near-surface ecosystems. As part of the FP7 RISCS (Research into Impacts and Safety in CO2 Storage) project a geochemical, botanical and microbiological study have been conducted on a natural CO2 vent in Florina, Greece and the findings are compared with the results drawn from Latera, Italy and Laacher See, Germany. Plant and microbial communities appear to have adapted to long-term CO2 exposure. Therefore the findings may not be representative of the effects of potential leakage from man made storage sites.

Impacts of long-term CO2 exposure on environmental processes and microbial populations of near-surface soils are poorly understood. This near-surface long-term CO2 injection study demonstrated that soil microbiology and geochemistry is influenced more by seasonal parameters than elevated CO2. Soil samples were taken during a 3-year field experiment including sampling campaigns before, during and after 24 months of continuous CO2 injection. CO2 concentrations within CO2-injected plots increased up to 23% during the injection period. No CO2 impacts on geochemistry were detected over time. In addition, CO2-exposed samples did not show significant changes in microbial CO2 and CH4 turnover rates compared to reference samples. Likewise, no significant CO2-induced variations were detected for the abundance of Bacteria, Archaea (16S rDNA) and gene copy numbers of the mcrA gene, Crenarchaeota and amoA gene. The majority (75%–95%) of the bacterial sequences were assigned to five phyla: Firmicutes, Proteobacteria, Actinobacteria, Acidobacteria and Bacteroidetes. The majority of the archaeal sequences (85%–100%) were assigned to the thaumarchaeotal cluster I.1b (soil group). Univariate and multivariate statistical as well as principal component analyses showed no significant CO2-induced variation. Instead, seasonal impacts especially temperature and precipitation were detected.

This paper documents the concentration of total arsenic and individual arsenic species in four soft-bottom benthic polychaetes (Perenereis cultifera, Ganganereis sootai, Lumbrinereis notocirrata and Dendronereis arborifera) along with host sediments from Sundarban mangrove wetland, India. An additional six sites were considered exclusively for surface sediments for this purpose. Polychaetes were collected along with the host sediments and measured for their total arsenic content using inductively coupled plasma mass spectrometry. Arsenic concentrations in polychaete body tissues varied greatly, suggesting species-specific characteristics and inherent peculiarities in arsenic metabolism. Arsenic was generally present in polychaetes as arsenate (As(V) ranges from 0.16 to 0.50 mg kg(-1)) or arsenite (As(III) ranges from 0.10 to 0.41 mg kg(-1)) (30-53 % as inorganic As) and dimethylarsinic acid (DMA(V)1-25 %). Arsenobetaine (AB16 %), and PO(4)-arsenoriboside (8-48 %) were also detected as minor constituents, whilst monomethylarsonic acid (MA(V)) was not detected in any of the polychaetes. The highest total As (14.7 mg kg(-1) dry wt) was observed in the polychaete D. arborifera collected from the vicinity of a sewage outfall in which the majority of As was present as an uncharacterised compound (10.3 mg kg(-1) dry wt) eluted prior to AB. Host sediments ranged from 2.5 to 10.4 mg kg(-1) of total As. This work supports the importance of speciation analysis of As, because of the ubiquitous occurrence of this metalloid in the environment, and its variable toxicity depending on chemical form. It is also the first work to report the composition of As species in polychaetes from the Indian Sundarban wetlands.

The objective of this study was to evaluate the ability of a preoperative serum CA125 to predict whether optimal debulking (OD) could be achieved for patients with stage III and IV epithelial ovarian cancer (EOC). The records of consecutive patients who underwent primary surgery for EOC at Indiana University Hospital between January 1997 and January 2003 were reviewed. Eligibility criteria included FIGO stage III/IV disease, surgery by gynecologic oncology faculty, preoperative CA125, and an operative note clearly defining volume of residual disease. The Medcalc software statistical package was used to generate a receiver-operating characteristic (ROC) curve. Two hundred and eighty-nine cases of stage III/IV EOC were identified, of which 164 met the eligibility criteria. Serum CA125/=400 was associated with OD/=75% of the time. Conversely, OD was achieved in/=40% of patients with CA125/=4500. The area under the ROC curve for CA125 was .670. The OD rate for those with and without ascites was 49% and 79%, respectively (P0.001). In a multivariate analysis using CA125, age, and ascites, the area under the curve was 0.686. We conclude that preoperative serum CA125 did not reliably predict OD in patients with stage III-IV EOC.

Selected European studies have illustrated the impacts of elevated CO2 concentrations in shallow soils on pasture. For the first time, general unified conclusions can be made, providing CO2 thresholds where effects on plants and soil microbiology are observed and making recommendations on how this information can be used when planning projects for CO2 storage. The sites include those where CO2 is being naturally released to the atmosphere from deep geological formations; and a non-adapted site, with no previous history of CO2 seepage, where CO2 has been injected into the unsaturated soil horizon. Whilst soil gas concentrations will be influenced by flux rates and other factors, the results suggest that a concentration of between 10% and 15% CO2 soil gas at 20 cm depth, which is within the root zone, is an important threshold level for observing changes in plant coverage. Site-specific plant ‘indicators’ are also observed for CO2 concentrations at ≥35%. Microbiological changes are seen where CO2 soil gas concentrations are between 15% and 40%. As part of site characterisation, an evaluation of the risks of leakage and their potential environmental impacts should be undertaken.

The measurement of gas concentrations and fluxes in the soil and atmosphere is a powerful tool for monitoring geological carbon capture and storage (CCS) sites because the analyses are made directly in the biosphere in which we live. These methods can be used to both find and accurately quantifying leaks, and are visible and tangible data for public and ecosystem safety. To be most reliable and accurate, however, the measurements must be interpreted in the context of natural variations in gas concentration and flux. Such baseline data vary both spatially and temporally due to natural processes, and a clear understanding of their values and distributions is critical for interpreting near-surface gas monitoring techniques. The best example is CO2 itself, as the production of this gas via soil respiration can create a wide range of concentrations and fluxes that must be separated from, and not confused with, CO2 that may leak towards the surface from a storage reservoir. The present article summarizes baseline studies performed by the authors at various sites having different climates and geological settings from both Europe and North America, with focus given to the range of values that can result from near surface processes and how different techniques or data processing approaches can be used to help distinguish a leakage signal from an anomalous, shallow biogenic signal.

Carbon Capture and Storage is increasingly seen as a way of combating rising CO2 concentrations in the atmosphere. Although storage sites will be designed for zero leakage it is important to consider the possible environmental effects in the unlikely event that leakage does occur, for both risk and environmental impact assessments. The potential responses of ecosystems depend on CO2 concentrations, event duration, the sensitivities of different organisms and external environmental factors

Estimates of absorbed dose rates to wildlife from exposure to natural background radionuclides are required to put estimates of dose rates arising from regulated releases of radioactivity and proposed benchmarks into context. Recent review papers have estimated dose rates to wildlife from (40)K, and (238)U and (232)Th series radionuclides. However, only one study previous has considered the potential dose rates to burrowing animals from inhaled (222)Rn and its daughter products. In this paper we describe a study conducted at seven sites in northwest England. Passive track etch detectors were used to measure the (222)Rn concentrations in artificial burrows over a period of approximately one year. Results suggest that absorbed dose rates to burrowing mammals as a consequence of exposure to (222)Rn are likely to be at least an order of magnitude higher than those suggested in previous evaluations of natural background exposure rates which had omitted this radionuclide and exposure pathway. Dose rates in some areas of Great Britain will be considerably in excess of incremental no-effects benchmark dose rates suggested for use as screening levels. Such advised benchmark dose rates need to be better put into context with background dose rates, including exposure to (222)Rn, to ensure credibility; although the context will be determined by the purpose of the benchmark and the assessment level.

CO2 capture and geological storage offers an option for reducing man-made greenhouse gas emissions. But one major concern related to geological CO2 storage is the possibility of leakage from the reservoir and subsequent effects on the environment, which cannot completely be excluded. This study aims at investigating the environmental impact of CO2 release from reservoirs into near surface terrestrial environments. To understand the effect of CO2 leakage on such an ecosystem, detailed knowledge on the abundance and diversity of plants and microorganisms is essential. Therefore, an ecosystem study has been conducted within the Network of Excellence “CO2GeoNet” on a natural CO2 vent at the Laacher See, Germany. Near surface CO2 conditions and CO2 fluxes of the venting area were described by means of conventional soil gas measurement equipment, and brought up the difference between the CO2 anomalies and their surroundings. A comparison of the soil columns between control sites and the centre of the venting area showed a small but significant change in the soil pH below 10 cm. The botanical survey revealed vegetation changes which, like the investigation of important soil microbial communities, showed significant differences between the CO2-rich sites (up to 90% and more of soil gas), medium CO2 sites (∼20%), and control locations with background CO2 concentrations. The ecosystem appears to be adapted to the different conditions through species substitution or adaptation, showing a shift towards anaerobic and acidotolerant to acidophilic species under elevated CO2 concentrations. It is hoped that the final outcome of this ongoing study will be the identification of possible botanical and microbial indicators, whose presence or absence provides easily detectable evidence for leakage of CO2 from deep reservoirs into near surface terrestrial ecosystems.

New methods for the monitoring of CO2 near the ground surface at geological CO2 storage sites have been tested over areas of natural CO2 emission. Mobile open path laser measurements and ground-surface portable infrared measurements show great promise for rapid assessment of large areas. Such techniques would help to focus more detailed investigations needed to verify the extent and source of the gas being emitted. It is envisaged that they would be used in conjunction with established field and laboratory techniques and continuous monitoring methods as part of an overall monitoring strategy for a CO2 storage site.

Synopsis 222 Rn, a natural radioactive gas produced by the radioactive decay of 238 U, accounts for about 50% of the total radiation dose to the average person in the UK. Geology is the most important factor controlling the source and distribution of radon; which has been linked to an increased risk of lung cancer. In order to prevent the public receiving high exposures to radon, it is necessary to identify those areas most at risk. We present results of new mapping of radon potential for Scotland using a method that allows the spatial variation in radon potential to be delineated both within and between geological groupings. The main geological and geochemical associations with moderate to high radon potential areas are described. The highest radon potential values in Scotland are associated with U-rich, highly evolved Siluro-Devonian biotite granite intrusions, notably those clustered within a zone to the west of Aberdeen and at Helmsdale, in Caithness. U mineralization plays a role in areas including the Helmsdale granite and the Middle Old Red Sandstone of the Orcadian Basin. Elevated radon potential is also associated with limestones – where fracture permeability is influential – and with Ordovician–Silurian greywackes. The radon potential of unconsolidated deposits, and how this affects the radon potential of the underlying bedrock, reflects both their permeabilities and their compositions.