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Woeilih Jeng - One of the best experts on this subject based on the ideXlab platform.
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Coprostanol in a sediment core from the anoxic tan shui estuary taiwan
Estuarine Coastal and Shelf Science, 1996Co-Authors: Woeilih JengAbstract:A short sediment core with a length of approximately 40 cm taken from the anoxic Tan-Shui estuary, Taiwan, was analysed for extractable and bound Coprostanol (5β-cholestan-3β-ol), cholestanol (5α-cholestan-3β-ol) and cholesterol (cholest-5-en-3β-ol). Extractable ΣCoprostanol and cholestanol concentrations exhibit an abrupt change at a depth of about 20 cm, which supposedly marks the time when a sewage treatment plant became operational in the estuary in 1980. The ΣCoprostanol/cholesterol and cholestanol/cholesterol ratios are comparatively higher in sediment than in the sewage effluent, implying some degree of diagenesis in the extractable phase. Anoxicity must have played a crucial role in the preservation and diagenesis of the sterols. In the upper layer (c. top 20 cm), the concentrations of extractable ΣCoprostanol, normalized to total organic carbon (TOC), increase down the core. Extractable cholestanol exhibits the same trend, but extractable cholesterol shows the opposite trend. This indicates cholesterol reduction to these two stanols. In addition, both bound ΣCoprostanol/TOC and cholestanol/TOC display a decreasing trend with core depth and no pronounced concentration change at 20 cm depth. The averages of percent bound sterols are in the following order: cholesterol > Coprostanol>cholestanol.
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Coprostanol distribution in marine sediments off southwestern taiwan
Environmental Pollution, 1996Co-Authors: Woeilih Jeng, Joe Wang, Bor Cheng HanAbstract:One of the major industries in southern Taiwan is pigfarming along the Kaoping River; some two million animals are being raised along the river banks. Excretions from pigs, treated and untreated, are discharged directly into the river and eventually carried to the sea. Twenty-four surface sediments and one sediment core off southwestern Taiwan were analyzed to determine quantitatively the extent of Coprostanol addition and its distribution and to obtain the input of Coprostanol over the past. Geographically, the percent Coprostanol is highest around the river mouth, and decreases to about 1% at the shelf break and about 0% at a distance of approximately 40 nautical miles (74 km) from the river mouth. The progressive seaward decline of percent Coprostanol from the river mouth can be attributed to [1] dilution of Coprostanol by uncontaminated sediment and/or sediment containing relatively lower levels of Coprostanol, [2] dilution of Coprostanol by biogenic sterols, and [3] probably degradation of Coprostanol. Further, the Kaoping Canyon sediments contain relatively high percent Coprostanol; this can be attributed to [1] a more direct input of the river sediments because the canyon is well aligned with the river, [2] currents in the canyon being alternate upcanyon and downcanyon which tend to keep sediments in the canyon, and [3] the possible blocking effect of a topographic high in the canyon. A sediment core exhibits comparatively higher percent Coprostanol in the top 15 cm, indicating an increased input of Coprostanol over the past 20 years.
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sedimentary Coprostanol in kaohsiung harbour and the tan shui estuary taiwan
Marine Pollution Bulletin, 1994Co-Authors: Woeilih Jeng, Bor Cheng HanAbstract:Coprostanol in sediments from Kaohsiung Harbour and the Tan-Shui Estuary has been analysed. In the Kaohsiung Harbour sediments, Coprostanol has a concentration range between 0.58 and 128 μg g−1 dry wt with a mean of 20.8 μg g−1 dry wt; higher concentrations are found near the mouths of rivers. Moreover, a significant log-log correlation is found between total Coprostanol concentration and oil hydrocarbon concentration (r=0.803∗). In Tan-Shui Estuary sediments, Coprostanol ranges in concentration from 1.00 to 230 μg g−1 dry wt with an average of 63.5 μg g−1 dry wt; relatively high levels of Coprostanol (> 10 μg g−1) with 5β5β+5α cholestanol ratios > 0.7 indicate positive sewage pollution. This probably results from an input from the sewage outfall, anoxicity, shallow water depths, inadequate tidal flushing, etc. Additionally, highly significant correlations have been found for Coprostanol and cholesterol (r=0.986∗) and for cholestanol and cholesterol (r=0.981∗); these relationships are thought to be mediated predominantly by sediment micro-organisms in the reducing environment.
H Sabik - One of the best experts on this subject based on the ideXlab platform.
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evidence of Coprostanol estrogenicity to the freshwater mussel elliptio complanata
Environmental Pollution, 2001Co-Authors: F Gagne, C Blaise, B Lachance, G I Sunahara, H SabikAbstract:Coprostanol (5β(H)-cholestan-3βol) is a reduced metabolite of cholesterol produced by micro-organisms found in the intestinal tract of mammals. This substance abounds in urban effluents and is accumulated by organisms living in the vicinity of municipal effluent outfalls. In an earlier study, freshwater mussels exposed to contaminated river water for 62 days accumulated large quantities of Coprostanol (Cop) in their soft tissues (16 μg/g dry wt.). Moreover, these mussels were found to have elevated levels of vitellin in their hemolymphs, suggesting estrogenic effects. Although municipal wastewaters are known to contain other estrogenic compounds capable of inducing Vn synthesis in mussels, the estrogenic potential of Coprostanol was singled out for examination. To this end, mussels were first injected with concentrations of Coprostanol via the abductor muscle route, and allowed to stand in aerated water for 72 h at 15°C. The levels of Vn in mussel hemolymph were assayed using the organic alkali-labile phosphate method. A competitive estradiol-binding assay was then devised to measure the ability of Coprostanol to compete in the binding of fluorescein-labeled estradiol-albumin to cytosolic proteins. Coprostanol partially reversed the binding of labeled estradiol-albumin to cytosolic proteins with an EC50 of 1 mM. In addition, injections of Coprostanol and estradiol-17β led to increased levels of vitellins in the hemolymph of treated mussels. Moreover, incubation of cop in gonad homogenate extracts in the presence of NADPH led to the formation of two compounds, as determined by high-performance thin-layer chromatography. One of these compounds appears to be the C17 oxidation product of Coprostanol, whose polarity is similar to that of estradiol. The results present evidence that Coprostanol is estrogenic to freshwater mussels.
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evidence of Coprostanol estrogenicity to the freshwater mussel elliptio complanata
Environmental Pollution, 2001Co-Authors: F Gagne, C Blaise, B Lachance, G I Sunahara, H SabikAbstract:Coprostanol (5 beta (H)-cholestan-3 beta ol) is a reduced metabolite of cholesterol produced by micro-organisms found in the intestinal tract of mammals. This substance abounds in urban effluents and is accumulated by organisms living in the vicinity of municipal effluent outfalls. In an earlier study, freshwater mussels exposed to contaminated river water for 62 days accumulated large quantities of Coprostanol (Cop) in their soft tissues (16 micrograms/g dry wt.). Moreover, these mussels were found to have elevated levels of vitellin in their hemolymphs, suggesting estrogenic effects. Although municipal wastewaters are known to contain other estrogenic compounds capable of inducing Vn synthesis in mussels, the estrogenic potential of Coprostanol was singled out for examination. To this end, mussels were first injected with concentrations of Coprostanol via the abductor muscle route, and allowed to stand in aerated water for 72 h at 15 degrees C. The levels of Vn in mussel hemolymph were assayed using the organic alkali-labile phosphate method. A competitive estradiol-binding assay was then devised to measure the ability of Coprostanol to compete in the binding of fluorescein-labeled estradiol-albumin to cytosolic proteins. Coprostanol partially reversed the binding of labeled estradiol-albumin to cytosolic proteins with an EC50 of 1 mM. In addition, injections of Coprostanol and estradiol-17 beta led to increased levels of vitellins in the hemolymph of treated mussels. Moreover, incubation of cop in gonad homogenate extracts in the presence of NADPH led to the formation of two compounds, as determined by high-performance thin-layer chromatography. One of these compounds appears to be the C17 oxidation product of Coprostanol, whose polarity is similar to that of estradiol. The results present evidence that Coprostanol is estrogenic to freshwater mussels.
Bor Cheng Han - One of the best experts on this subject based on the ideXlab platform.
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Coprostanol distribution in marine sediments off southwestern taiwan
Environmental Pollution, 1996Co-Authors: Woeilih Jeng, Joe Wang, Bor Cheng HanAbstract:One of the major industries in southern Taiwan is pigfarming along the Kaoping River; some two million animals are being raised along the river banks. Excretions from pigs, treated and untreated, are discharged directly into the river and eventually carried to the sea. Twenty-four surface sediments and one sediment core off southwestern Taiwan were analyzed to determine quantitatively the extent of Coprostanol addition and its distribution and to obtain the input of Coprostanol over the past. Geographically, the percent Coprostanol is highest around the river mouth, and decreases to about 1% at the shelf break and about 0% at a distance of approximately 40 nautical miles (74 km) from the river mouth. The progressive seaward decline of percent Coprostanol from the river mouth can be attributed to [1] dilution of Coprostanol by uncontaminated sediment and/or sediment containing relatively lower levels of Coprostanol, [2] dilution of Coprostanol by biogenic sterols, and [3] probably degradation of Coprostanol. Further, the Kaoping Canyon sediments contain relatively high percent Coprostanol; this can be attributed to [1] a more direct input of the river sediments because the canyon is well aligned with the river, [2] currents in the canyon being alternate upcanyon and downcanyon which tend to keep sediments in the canyon, and [3] the possible blocking effect of a topographic high in the canyon. A sediment core exhibits comparatively higher percent Coprostanol in the top 15 cm, indicating an increased input of Coprostanol over the past 20 years.
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sedimentary Coprostanol in kaohsiung harbour and the tan shui estuary taiwan
Marine Pollution Bulletin, 1994Co-Authors: Woeilih Jeng, Bor Cheng HanAbstract:Coprostanol in sediments from Kaohsiung Harbour and the Tan-Shui Estuary has been analysed. In the Kaohsiung Harbour sediments, Coprostanol has a concentration range between 0.58 and 128 μg g−1 dry wt with a mean of 20.8 μg g−1 dry wt; higher concentrations are found near the mouths of rivers. Moreover, a significant log-log correlation is found between total Coprostanol concentration and oil hydrocarbon concentration (r=0.803∗). In Tan-Shui Estuary sediments, Coprostanol ranges in concentration from 1.00 to 230 μg g−1 dry wt with an average of 63.5 μg g−1 dry wt; relatively high levels of Coprostanol (> 10 μg g−1) with 5β5β+5α cholestanol ratios > 0.7 indicate positive sewage pollution. This probably results from an input from the sewage outfall, anoxicity, shallow water depths, inadequate tidal flushing, etc. Additionally, highly significant correlations have been found for Coprostanol and cholesterol (r=0.986∗) and for cholestanol and cholesterol (r=0.981∗); these relationships are thought to be mediated predominantly by sediment micro-organisms in the reducing environment.
F Gagne - One of the best experts on this subject based on the ideXlab platform.
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evidence of Coprostanol estrogenicity to the freshwater mussel elliptio complanata
Environmental Pollution, 2001Co-Authors: F Gagne, C Blaise, B Lachance, G I Sunahara, H SabikAbstract:Coprostanol (5β(H)-cholestan-3βol) is a reduced metabolite of cholesterol produced by micro-organisms found in the intestinal tract of mammals. This substance abounds in urban effluents and is accumulated by organisms living in the vicinity of municipal effluent outfalls. In an earlier study, freshwater mussels exposed to contaminated river water for 62 days accumulated large quantities of Coprostanol (Cop) in their soft tissues (16 μg/g dry wt.). Moreover, these mussels were found to have elevated levels of vitellin in their hemolymphs, suggesting estrogenic effects. Although municipal wastewaters are known to contain other estrogenic compounds capable of inducing Vn synthesis in mussels, the estrogenic potential of Coprostanol was singled out for examination. To this end, mussels were first injected with concentrations of Coprostanol via the abductor muscle route, and allowed to stand in aerated water for 72 h at 15°C. The levels of Vn in mussel hemolymph were assayed using the organic alkali-labile phosphate method. A competitive estradiol-binding assay was then devised to measure the ability of Coprostanol to compete in the binding of fluorescein-labeled estradiol-albumin to cytosolic proteins. Coprostanol partially reversed the binding of labeled estradiol-albumin to cytosolic proteins with an EC50 of 1 mM. In addition, injections of Coprostanol and estradiol-17β led to increased levels of vitellins in the hemolymph of treated mussels. Moreover, incubation of cop in gonad homogenate extracts in the presence of NADPH led to the formation of two compounds, as determined by high-performance thin-layer chromatography. One of these compounds appears to be the C17 oxidation product of Coprostanol, whose polarity is similar to that of estradiol. The results present evidence that Coprostanol is estrogenic to freshwater mussels.
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evidence of Coprostanol estrogenicity to the freshwater mussel elliptio complanata
Environmental Pollution, 2001Co-Authors: F Gagne, C Blaise, B Lachance, G I Sunahara, H SabikAbstract:Coprostanol (5 beta (H)-cholestan-3 beta ol) is a reduced metabolite of cholesterol produced by micro-organisms found in the intestinal tract of mammals. This substance abounds in urban effluents and is accumulated by organisms living in the vicinity of municipal effluent outfalls. In an earlier study, freshwater mussels exposed to contaminated river water for 62 days accumulated large quantities of Coprostanol (Cop) in their soft tissues (16 micrograms/g dry wt.). Moreover, these mussels were found to have elevated levels of vitellin in their hemolymphs, suggesting estrogenic effects. Although municipal wastewaters are known to contain other estrogenic compounds capable of inducing Vn synthesis in mussels, the estrogenic potential of Coprostanol was singled out for examination. To this end, mussels were first injected with concentrations of Coprostanol via the abductor muscle route, and allowed to stand in aerated water for 72 h at 15 degrees C. The levels of Vn in mussel hemolymph were assayed using the organic alkali-labile phosphate method. A competitive estradiol-binding assay was then devised to measure the ability of Coprostanol to compete in the binding of fluorescein-labeled estradiol-albumin to cytosolic proteins. Coprostanol partially reversed the binding of labeled estradiol-albumin to cytosolic proteins with an EC50 of 1 mM. In addition, injections of Coprostanol and estradiol-17 beta led to increased levels of vitellins in the hemolymph of treated mussels. Moreover, incubation of cop in gonad homogenate extracts in the presence of NADPH led to the formation of two compounds, as determined by high-performance thin-layer chromatography. One of these compounds appears to be the C17 oxidation product of Coprostanol, whose polarity is similar to that of estradiol. The results present evidence that Coprostanol is estrogenic to freshwater mussels.
Rhys Leeming - One of the best experts on this subject based on the ideXlab platform.
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degradation and responses of Coprostanol and selected sterol biomarkers in sediments to a simulated major sewage pollution event a microcosm experiment under sub tropical estuarine conditions
Organic Geochemistry, 2008Co-Authors: Catherine Pratt, Jan Warnken, Rhys Leeming, Michael J Arthur, Darren GriceAbstract:Abstract A microcosm experiment was conducted to investigate the degradation of Coprostanol and related sterol biomarkers and Escherichia coli in ‘natural’ sediments from a highly mixed (marine and estuarine) sub-tropical environment following a simulated pollution event. This experiment revealed that sterols are synthesised and degraded over time by auto- and hetero trophic organisms within the sediment matrix from a onetime addition of a sewage/effluent seawater mixture. Coprostanol was the only sterol to degrade continually, with only minor fluctuations (synthesis/degradation) over a time period of two months. Results further revealed a sharp decline of Coprostanol within the first week. From this it could be concluded that, without any further addition, external inputs of Coprostanol are reduced to background levels within this time period. Therefore, removal of Coprostanol after six days was 94% and 73% in mud and sand, respectively. The rate of removal of Coprostanol was much higher in mud than sand, reflecting a higher level of microbial activity in muddy sediments for assimilation of sterols. Bacterial indicators levelled off more quickly than Coprostanol degraded (i.e. within 2 days), which shows that Coprostanol is a more conservative sediment quality indicator for tracing human derived sewage in coastal sediments than indicator bacteria.
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Degradation of faecal sterols in urine for assessment of faecal cross-contamination in source-separated human urine and urine storage tank sediment
Water Research, 1999Co-Authors: K.annika Sundin, Rhys Leeming, Thor Axel StenströmAbstract:Abstract The degradation of the faecal sterol Coprostanol and its precursor cholesterol, were determined in source-separated human urine and urine tank sediment. The aim was to assess their potential as biomarkers of faecal cross-contamination in source-separated waste systems since traditional microbial indicators have been shown not to be reliable in this context. Investigations were performed at 4 and 20°C in collected human urine and urine tank sediment to which human faeces and synthetic cholesterol and Coprostanol were added. The individual degradation experiments were performed over periods of up to 118 days and represented a wide concentration range both for the urine and the urine tank sediment. Coprostanol showed no significant degradation in either the urine or urine tank sediment when faeces or synthetic Coprostanol were added. Neither the normalised variance for the individual slopes, nor the combined regression analysis showed any significant difference from the common slope of zero. For cholesterol no significant degradation was found in the urine tank sediment, but based on pooled data, a moderate decrease occurred in the urine. This was most evident for endogenous cholesterol in the urine at low concentrations where 38 and 55% of the original amounts were lost at 4 and 20°C, respectively. The daily rate of loss of cholesterol based on the regression analysis was 0.73 μ g l −1 per day. It is concluded that amounts of Coprostanol in urine collection tanks can be used as an indicator of faecal cross-contamination cumulatively occurring over the collection period. Together with die-off data of indicator organisms and pathogens, establishment of a baseline risk assessment would now be possible in relation to storage, handling and reuse of the urine.
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assessment of the sources transport and fate of sewage derived organic matter in port phillip bay australia using the signature lipid Coprostanol
Marine and Freshwater Research, 1999Co-Authors: John K Volkman, Rhys Leeming, Teresa Oleary, Peter D NicholsAbstract:To evaluate the distribution of faecal material in Port Phillip Bay, surface sediments from sites throughout the bay and inflowing water courses were analysed for fatty acids and sterols. Water samples were also collected to identify possible sources of faecal contamination. Bay sediments had total fatty acid concentrations between 4 and 183 µg g–1 (dry weight) and total sterol concentrations between 0.6 and 39.2 µg g–1. Creek sediments contained more sterols, ranging from 22.8–148 µg g–1. These lipid distributions suggest that the bulk of the labile organic matter derives from marine microalgae, primarily diatoms. Coprostanol (5β-cholestan-3β-ol), a sterol often used as an indicator of faecal contamination, was also present. Concentrations ranged from <0.01–0.55 µg g–1 in surface sediments, with values over 0.25 µg g–1 and 5β-/5α-C27 stanol ratios greater than 0.4, indicative of sewage inputs. A clearer picture of distributions of sewage-derived organic matter was obtained when Coprostanol was normalized to total organic matter rather than sediment dry weight. Areas showing higher Coprostanol concentrations included those adjacent to the main sewage treatment plant and several low-volume drains and creeks, indicating localized problems of sewage contamination.
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concentrations of Coprostanol that correspond to existing bacterial indicator guideline limits
Water Research, 1996Co-Authors: Rhys Leeming, Peter D NicholsAbstract:Abstract Coprostanol is a faecal sterol that has been proposed as an alternative measure of faecal pollution. While the technique has been used successfully to trace sewage-derived organic matter in a range of environments, it has not been embraced for use as a water quality indicator. This is mostly because of a lack of epidemiological evidence relating Coprostanol abundance to any health risk. However, there is a valuable reason why the concentration of Coprostanol should be related as quantitatively as possible to the abundance of bacterial indicators currently used to measure faecal pollution. The measurement of Coprostanol (and concurrently other faecal sterols) offers many diagnostic and quantitative advantages over traditional techniques for detecting human sewage pollution versus faecal contamination from animal sources. Knowing the amount of Coprostanol expected given a certain amount of human sewage pollution would provide a measure against which water managers could quantitatively assess faecal pollution as a whole and relate that assessment to variables with which they are more familiar. This study determines the relationships between Coprostanol concentrations and indicator bacterial counts and synthesises the results from several environments to propose Coprostanol concentrations broadly equivalent to existing bacterial standards. Our data suggest that 60 and 400 ng L −1 of Coprostanol correspond to currently defined primary and secondary contact limits for bacteria measured as thermotolerant coliforms (commonly referred to as faecal coliforms) or enterococci.
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use of capillary gas chromatography for measuring fecal derived sterols application to stormwater the sea surface microlayer beach greases regional studies and distinguishing algal blooms and human and non human sources of sewage pollution
Journal of Chromatography A, 1996Co-Authors: Peter D Nichols, Rhys Leeming, Mark S Rayner, Val LathamAbstract:The sterol composition, including the fecal biomarker Coprostanol, from a variety of sample types was determined by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The Coprostanol concentration in field samples readily provided an estimate of human fecal pollution. The technique was successfully used for stormwater, the sea-surface microlayer, beach sands and greases, and in regional studies of coastal sediments. Sterol profiles can be used to distinguish human and non-human sources of sewage pollution and algal blooms. Development of appropriate component ratios, both within the sterol fraction and between compounds classes, may provide a useful mechanism to further exploit sterol data. For sewage-containing samples, it may be possible to extend the data comparison, and calculation of key ratios, to include bacteriological parameters. Collectively, the use of sterol compositional data can complement other physical, chemical and biological measurements obtained in environmental studies.