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Treated sewage, stormwater runoff and industrial waste are sources of chemical contamination in coastal sediments. Although studies of sedimentary chemistry have resulted in stringent laws on discharging toxic chemicals into the sea, the... more
Treated sewage, stormwater runoff and industrial waste are sources of chemical contamination in coastal sediments. Although studies of sedimentary chemistry have resulted in stringent laws on discharging toxic chemicals into the sea, the more toxic chemicals can have lasting effects on the environment.
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AeSTV, ACr: We recovered a single, calcite-coated phosphorite nodule, 8-10 cm in diameter, buried 70-80 em deep in a box core of anoxic, organic-rich, varved sediment from the central Santa Barbara Basin (SBB) off southern California.... more
AeSTV, ACr: We recovered a single, calcite-coated phosphorite nodule, 8-10 cm in diameter, buried 70-80 em deep in a box core of anoxic, organic-rich, varved sediment from the central Santa Barbara Basin (SBB) off southern California. Varve chronology enables ...
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... cores. Full-size table (<1K). View Within Article. 3.1.2. San Pablo Bay. The total pesticides range in concentration from 0.3 (near detection limits) to 59 ng/g (Fig. ... 3.2. Non-DDT pesticides in Richardson... more
... cores. Full-size table (<1K). View Within Article. 3.1.2. San Pablo Bay. The total pesticides range in concentration from 0.3 (near detection limits) to 59 ng/g (Fig. ... 3.2. Non-DDT pesticides in Richardson and San Pablo cores. The ...
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... & Kaplan (1990) composite (November 87), Glass tubes subcores were obtained from Soutar-type box cores collected in Santa Monica Basra (Fig. ... Finney and Huh, 1989B.P. Finney and Ch-A Huh, History of metal pollution in the... more
... & Kaplan (1990) composite (November 87), Glass tubes subcores were obtained from Soutar-type box cores collected in Santa Monica Basra (Fig. ... Finney and Huh, 1989B.P. Finney and Ch-A Huh, History of metal pollution in the Southern California Bight: an update, Environ. ...
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Research Interests: Environmental Science, Carbon, MARINE POLLUTION, Brazil, Environmental Monitoring, and 15 moreMagnetic Resonance Spectroscopy, Multidisciplinary, Humans, Environmental Effect, Nitrogen, Chemical Analysis, Environmental Impact, Marine Sediment, Gulf of Alaska, Moving average, Human Activity, Molecular weight, Eastern Bering Sea, Geologic Sediments, and High Molecular Weight
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Research Interests: Immunology, Membrane Proteins, Oxidative Stress, Macrophages, Immunology of the Gut, and 15 moreFlavonoids, Antioxidants, Cell line, Mice, Vehicle Emissions, Animals, Quinones, The, Heme Oxygenase, Polycyclic aromatic hydrocarbons (PAHs), N-Acetylcysteine, Oxidation-Reduction, Response Elements, Enzyme Induction, and ketones
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Surface sediments from the Outer Continental Shelf of Alaska were analyzed for hydrocarbons as part of an environmental survey sponsored by NOAA/BLM. Sediments were collected from the proposed oil lease areas of Beaufort Sea, southeastern... more
Surface sediments from the Outer Continental Shelf of Alaska were analyzed for hydrocarbons as part of an environmental survey sponsored by NOAA/BLM. Sediments were collected from the proposed oil lease areas of Beaufort Sea, southeastern Bering Sea, Norton Sound, Navarin Basin, Gulf of Alaska, Kodiak Shelf and lower Cook Inlet. Data on normal and branched alkanes and di- and triterpenoids
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Butyltins have been measured for the first time in sediments from the deeper waters of the Santa Monica and San Pedro (SM/SP) basins of Southern California borderland. Core samples were collected from water depths ranging from 458 m in... more
Butyltins have been measured for the first time in sediments from the deeper waters of the Santa Monica and San Pedro (SM/SP) basins of Southern California borderland. Core samples were collected from water depths ranging from 458 m in the shelf to 906 m in the central basin. Surficial and a few subsurface sections from selected cores were analyzed for butyltins. The dominant components are generally dibutyl and monobutyltins (DBT and MBT, respectively). Microbial degradation of Tributyltin (TBT, the most toxic of the butyltin species) to DBT and MBT during the long range transport to deeper basins, as well as a lack of continuing inputs of TBT in the present times could justify the butyltins signatures found in the region. The levels of butyltins are in the lower range (below detection level, <1, to 14 ng of Sn g(-1)) relative to nearshore sediments. However, the results demonstrate that the butyltins are, indeed, found even in the sediments of the central basins of the Southern California borderland suggesting that deeper global oceanic regimes need to be further investigated for these compounds.
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Chapter 3 Chemical Oceanography and Geochemistry Robert P. Eganhouse and M. Indira Venkatesan Introduction Sources of Organic Matter and ... north toward Santa Barbara Basin and Point Conception where primary productivity is generally... more
Chapter 3 Chemical Oceanography and Geochemistry Robert P. Eganhouse and M. Indira Venkatesan Introduction Sources of Organic Matter and ... north toward Santa Barbara Basin and Point Conception where primary productivity is generally higher (Owen and Sanchez 1974 ...
... Printed in USA 0016-7037/86/S3.00 + .00 Terpenoid hydrocarbons in Hula peat: Structure and origins* MI VENKATESAN, E. RUTH ... have been identified in various geological samples, ie recent ma-rine sediments, soils, lignites, fossil... more
... Printed in USA 0016-7037/86/S3.00 + .00 Terpenoid hydrocarbons in Hula peat: Structure and origins* MI VENKATESAN, E. RUTH ... have been identified in various geological samples, ie recent ma-rine sediments, soils, lignites, fossil resins, coals, ancient rocks and petroleum ...
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Selected sterols (coprostanol, epicoprostanol, cholesterol, cholestanol), stanone (5ßcoprostanone) and linear alkylbenzenes (LABs) were measured in the surface sediments near Ferraz station sewage outfalls, in Admiralty Bay, King George... more
Selected sterols (coprostanol, epicoprostanol, cholesterol, cholestanol), stanone (5ßcoprostanone) and linear alkylbenzenes (LABs) were measured in the surface sediments near Ferraz station sewage outfalls, in Admiralty Bay, King George Island, South Shetland Islands. during the summer of 1997/98 using GC-FID and GC-MS. Total sterol concentrations varied between 0.21 and 10.4 μg g−1 dry sediment. Cholesterol was the major sterol at all sites, except at the sewage outfall, where coprostanol predominated. The concentration of coprostanol varied between 0.03 and 6.14 μg g−1 dry sediment, but the majority of the samples contained levels below 0.13 μg g−1 dry sediment. The parameters coprostanol+epicoprostanol in total sterols, coprostanol/epicoprostanol ratio versus % of cholesterol in total sterols and versus 5ß-coprostanone concentration were used to identify the sewage impacted locations in the study area. Only sites extending to 50m from the sewage outfall exhibited a sterol signal indicating sewage input. Total LABs varied from…
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... Sediments from the McMurdo region exhibit a sterol profile dominated by cholesterol, dinosterol, 13-sitosterol, and ... Identification and quantification of neutral fecal steroids by gas-liquid chromatography and mass spectrometry:... more
... Sediments from the McMurdo region exhibit a sterol profile dominated by cholesterol, dinosterol, 13-sitosterol, and ... Identification and quantification of neutral fecal steroids by gas-liquid chromatography and mass spectrometry: studies of ... Sterols as a measure of fecal pollution. ...
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The major objective of the present on-going project was to understand the processes involved in the cycling of organic carbon in the southern California Bight. This involves the evaluation of the relative flux of planktonic carbon to the... more
The major objective of the present on-going project was to understand the processes involved in the cycling of organic carbon in the southern California Bight. This involves the evaluation of the relative flux of planktonic carbon to the seafloor versus the import of terrestrial carbon components and the determination of the rate of decompositions of sedimenting organic matter in the waste column. These goals were achieved by the chemical characterization of sedimenting particles (from traps) as well as in the near surface sediments. At UCLA we have been focusing on the chemical characterization of selected classes of organic carbon compounds derived from different sources to understand the vertical flux and the chemical composition of the particulate organic matter which are controlled by complex transport, transformations, degradation and remineralization. 25 refs., 22 figs., 12 tabs.
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ABSTRACT The biogeochemical processes and the dynamics involved in the cycling and transport of organic carbon can be elucidated only by determining distributions of specific organic compounds associated with the particles. At UCLA, the... more
ABSTRACT The biogeochemical processes and the dynamics involved in the cycling and transport of organic carbon can be elucidated only by determining distributions of specific organic compounds associated with the particles. At UCLA, the quantitative data of the various organic compounds in the sediment cores and trap particulates from various depths of water column are gathered in order to construct a dynamic model of the biogeochemical cycling and processes occurring in the water and sedimentary columns. The sources of organic carbon in southern California Bight derive from both terrestrial and marine regimes. The varied organic carbon sources can be reasonably delineated within limits by the organic geochemical approach of determining various characteristic biomarkers, as well as a variety of pollution indicators. The distributions of organic biomarker compounds are characteristic of marine algae, terrestrial vascular plants, bacteria, etc. Presence of specific biomarkers also indicate the occurrence of specific species (e.g., dinosterol specific of dinoflagellates). There are some pollution indicators which one can look for in the marine environment to trace their origin to terrestrial inputs, i.e., polycyclic aromatic hydrocarbons from petroleum and combustion, coprostanol from sewage, etc. We study the distribution of many of these compounds and from a correlation of their relative abundance, an attempt is made to delineate marine vs terrestrial influx to the organic carbon in the study area. 18 refs., 1 fig., 4 tabs.
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The biogeochemical processes and the dynamics involved in the cycling and transport of organic carbon can be elucidated only by determining distributions of specific organic compounds associated with the particles. At UCLA, the... more
The biogeochemical processes and the dynamics involved in the cycling and transport of organic carbon can be elucidated only by determining distributions of specific organic compounds associated with the particles. At UCLA, the quantitative data of the various organic compounds in the sediment cores and trap particulates from various depths of water column are gathered in order to construct a dynamic model of the biogeochemical cycling and processes occurring in the water and sedimentary columns. The sources of organic carbon in southern California Bight derive from both terrestrial and marine regimes. The varied organic carbon sources can be reasonably delineated within limits by the organic geochemical approach of determining various characteristic biomarkers, as well as a variety of pollution indicators. The distributions of organic biomarker compounds are characteristic of marine algae, terrestrial vascular plants, bacteria, etc. Presence of specific biomarkers also indicate the...
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The spatial distribution, movement, and impact of the untreated wastewater outfall from McMurdo Station, Antarctica, were investigated under early austral summer conditions. The benthic environment was examined to determine the... more
The spatial distribution, movement, and impact of the untreated wastewater outfall from McMurdo Station, Antarctica, were investigated under early austral summer conditions. The benthic environment was examined to determine the distribution of Clostridium perfringens in sediment cores and the intestinal contents of native invertebrates and fish along a transect of stations. These stations extended ca. 411 m south of the outfall. The findings revealed that the concentration of C. perfringens decreased with depth in the sediment and distance from the outfall. High percentages of tunicates and sea urchins were colonized with this bacterium along the transect. Coprostanol concentrations were also measured in sediment samples taken from each of the transect stations, and a similar trend was observed. These results are in agreement with the findings of previous studies performed with the water column and collectively provide evidence that the disposal of domestic wastes deserves special c...