826 research outputs found
Methane emissions from oil and gas transport facilities – exploring innovative ways to mitigate environmental consequences
Climate change impacts are increasingly becoming more evident e.g. through heavy rainfall episodes and subsequent flooding. Methane is a significant greenhouse gas that has been linked to these impacts and the oil and gas industry is a major source of anthropogenic methane emission. Recent studies have suggested that the tropical region hold some unexpectedly high methane concentration and that the recent changes in the global methane burden are poorly understood. To address this research gap, we present a first effort to quantify methane emissions from one of the most vulnerable oil and gas infrastructures in Nigeria (a tropical country). A combination of the Intergovernmental Panel on Climate Change tier-1 approach and an adapted Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation model was used to estimate methane emissions from the system 2C transport pipeline. We then tested the hypothesis of no significant change in methane emissions trend from the pipeline using the between group t-test inferential analysis. Key findings include: (a) a crude oil throughput of 55,143 to 1,500,500 barrels (8767 to 238,561 m3) emitted methane ranging from 0.04734 to 1.288MT (± 50 to 200%) respectively, and (b) surprisingly, methane emissions along the system 2C pipeline seem to have continued without significant change between 2005, and 2008 to 2012 despite the low crude oil throughput in 2009. This indicates the likelihood of continuous but rising methane emissions from the pipeline network over a six-year period; and only further research can ascertain if similar trend can be observed elsewhere in the tropical region. These findings are unique and contribute to the current global debate on methane emissions from the largely unmonitored tropical region. Therefore, we recommend that stakeholders should set up a study plan for the identification and continuous monitoring of methane emissions from the key oil and gas infrastructure and explore opportunities for geoengineering applications as part of climate change mitigation. Coordinated engagement in international schemes such as the Natural Gas STAR program, Climate and Clean Air Coalition, Global Methane Initiative amongst others would promote strategic and measurable methane reduction plans in Nigeria and other countries within/outside the tropical region
The effect of unconfined mine tailings on the geochemistry of soils, sediments and surface waters of the Lousal area (Iberian Pyrite Belt, Southern Portugal)
Migration protocol to estimate metal exposure from mouthing copper and tin alloy objects
Carbon dioxide reduction in the building life cycle: a critical review
The construction industry is known to be a major contributor to environmental pressures due to its high energy consumption and carbon dioxide generation. The growing amount of carbon dioxide emissions over buildings’ life cycles has prompted academics and professionals to initiate various studies relating to this problem. Researchers have been exploring carbon dioxide reduction methods for each phase of the building life cycle – from planning and design, materials production, materials distribution and construction process, maintenance and renovation, deconstruction and disposal, to the material reuse and recycle phase. This paper aims to present the state of the art in carbon dioxide reduction studies relating to the construction industry. Studies of carbon dioxide reduction throughout the building life cycle are reviewed and discussed, including those relating to green building design, innovative low carbon dioxide materials, green construction methods, energy efficiency schemes, life cycle energy analysis, construction waste management, reuse and recycling of materials and the cradle-to-cradle concept. The review provides building practitioners and researchers with a better understanding of carbon dioxide reduction potential and approaches worldwide. Opportunities for carbon dioxide reduction can thereby be maximised over the building life cycle by creating environmentally benign designs and using low carbon dioxide materials
Carbohydrate‐Based Electron Donor for Biological Nitrate and Perchlorate Removal From Drinking Water
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142444/1/awwa0143.pd
Drawer compacted sand filter: a new and innovative method for on-site grey water treatment
Evaluation of an alternate method for sampling benthic macroinvertebrates in low-gradient streams sampled as part of the National Rivers and Streams Assessment
Nevada desert dust with heavy metals suppresses IgM antibody production
Systemic health effects from exposure to a complex natural dust containing heavy metals from the Nellis Dunes Recreation Area (NDRA) near Las Vegas, NV, were evaluated. Several toxicological parameters were examined following lung exposure to emissive dust from three geologic sediment types heavily used for recreational off- road activities: yellow sand very rich in arsenic (termed CBN 5); a shallow cover of loose dune sand overlying a gravelly subsoil bordering dune fields (termed CBN 6); and brown claystone and siltstone (termed CBN 7). Adult female B6C3F1 mice were exposed by oropharyngeal administration to these three types of geogenic dusts at 0.01–100 mg of dust/kg of body weight, once per week for four weeks. The median grain sizes were 4.6, 3.1, and 4.4 μm, for CBN 5, 6, and 7, respectively. Each type of dust contained quantifiable amounts of aluminum, vanadium, chromium, manganese, iron, cobalt, copper, zinc, arsenic, strontium, cesium, lead, uranium, and others. Descriptive markers of immunotoxicity, neurotoxicity, hematology, and clinical chemistry parameters were assessed. Notable among all three CBN units was a systemic, dose-responsive decrease in antigen-specific IgM antibody responses. Geogenic dust from CBN 5 produced more than a 70% suppression in IgM responses, establishing a lowest adverse effect level (LOAEL) of 0.01 mg/kg. A suppression in IgM responses and a corre- sponding increase in serum creatinine determined a LOAEL of 0.01 mg/kg for CBN 6. The LOAEL for CBN 7 was 0.1 mg/kg and also was identified from suppression in IgM responses. These results are of concern given the frequent off-road vehicle traffic and high visitor rates at the NDRA, estimated at 300,000 each year
Quantification of selected steroid hormones (17b-Estradiol and 17a-Ethynylestradiol) in wastewater treatment plants in Klang Valley (Malaysia)
Steroid estrogens, such as 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) are potent and were categorized as "Watch List" in Directive 2013/39/EU because of their potential risks to aquatic environment. Commercialized enzyme-linked immunosorbent assay (ELISA) kits have been used to quantify steroid estrogens in wastewater samples due to their simplicity, rapid, cost-effectiveness, and validated assays. Hence, this study aims to determine the occurrence and removal of steroid hormones in Malaysian wastewater treatment plants (WWTPs) by ELISA, to identify the association of removal efficiency (E2 and EE2) with respect to WWTPs operating conditions, and to assess the potential risks of steroid estrogens to aquatic environment and human. Results showed E2 concentration ranged from 88.2 ± 7.0 ng/L to 93.9 ± 6.9 ng/L in influent and 35.1 ± 17.3 ng/L to 85.2 ± 7.6 ng/L in effluent, with removal of 6.4%-63.0%. The EE2 concentration ranged from 0.2 ± 0.2 ng/L to 4.9 ± 6.3 ng/L in influent and 0.02 ± 0.03 ng/L to 1.0 ± 0.8 ng/L in effluent, with removal of 28.3-99.3%. There is a correlation between EE2 removal with total suspended solid (TSS) and oxidation reduction potential (ORP), and was statistically significant. Despite the calculated estrogenic activity for E2 and EE2 was relatively high, dilution effects could lower estrogenic response to aquatic environment. Besides, these six selected WWTPs have cumulative RQ values below the allowable limit, except WWTP 1. Relatively high precipitation (129-218 mm) could further dilute estrogens concentration in the receiving river. These outputs can be used as quantitative information for evaluating the occurrence and removal of steroid estrogens in Malaysian WWTPs
Passerine Exposure to Primarily PCDFs and PCDDs in the River Floodplains Near Midland, Michigan, USA
House wren (Troglodytes aedon), tree swallow (Tachycineta bicolor), and eastern bluebird (Sialia sialis) tissues collected in study areas (SAs) downstream of Midland, Michigan (USA) contained concentrations of polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs) greater than in upstream reference areas (RAs) in the region. The sum of concentrations of PCDD/DFs (ΣPCDD/DFs) in eggs of house wrens and eastern bluebirds from SAs were 4- to 22-fold greater compared to those from RAs, whereas concentrations in tree swallow eggs were similar among areas. Mean concentrations of ΣPCDD/DFs and sum 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (ΣTEQsWHO-Avian), based on 1998 WHO avian toxic equivalency factors, in house wren and eastern bluebird eggs ranged from 860 (430) to 1500 (910) ng/kg wet weight (ww) and 470 (150) to 1100 (510) ng/kg ww, respectively, at the most contaminated study areas along the Tittabawassee River, whereas mean concentrations in tree swallow eggs ranged from 280 (100) to 760 (280) ng/kg ww among all locations. Concentrations of ΣPCDD/DFs in nestlings of all studied species at SAs were 3- to 50-fold greater compared to RAs. Mean house wren, tree swallow, and eastern bluebird nestling concentrations of ΣPCDD/DFs and ΣTEQsWHO-Avian ranged from 350 (140) to 610 (300) ng/kg ww, 360 (240) to 1100 (860) ng/kg ww, and 330 (100) to 1200 (690) ng/kg ww, respectively, at SAs along the Tittabawassee River. Concentrations of ΣTEQsWHO-Avian were positively correlated with ΣPCDD/DF concentrations in both eggs and nestlings of all species studied. Profiles of relative concentrations of individual congeners were dominated by furan congeners (69–84%), primarily 2,3,7,8-tetrachlorodibenzofuran and 2,3,4,7,8-pentachlorodibenzofuran, for all species at SAs on the Tittabawassee and Saginaw rivers but were dominated by dioxin congeners at upstream RAs
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