Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 3787
Isolation of anaerobic oxalate-degrading bacteria from freshwater lake sediments
Enrichment cultures that anaerobically degraded oxalate were obtained from lake sediment inocula. From these, 5 pure cultures of anaerobic oxalate-degrading bacteria were isolated and partially characterized. The isolates were Gram-negative, non-sporeforming, non-motile, obligate anaerobes. Oxalate was required for growth and was stoichiometrically converted to formate; 14CO2 was also recovered wh
Authors
R. L. Smith, F.E. Strohmaier, Ronald S. Oremland
Copper and silver accumulation in transplanted and resident clams (Macoma balthica) in South San Francisco Bay
Accumulation of Cu and Ag by soft tissues of the deposit-feeding clam Macoma balthica was less than half in clams transplanted to a contaminated area than in clams native to that area. During a period of tissue growth, the transplants retained 50% and 90%, respectively, of the net Cu and Ag accumulated, but loss of metals from soft tissue by the resident population equalled net accumulation. Coppe
Authors
D.J. Cain, Samuel N. Luoma
Partitioning studies of coal-tar constituents in a two-phase contaminated ground-water system
Organic compounds derived from coal-tar wastes in a contaminated aquifer in St. Louis Park, Minnesota, were identified, and their partition coefficients between the tar phase and aqueous phase were determined and compared with the corresponding n-octanol/water partition coefficients. Coal tar contains numerous polycyclic aromatic compounds, many of which are suspected carcinogens or mutagens. Grou
Authors
Colleen E. Rostad, W. E. Pereira, M. F. Hult
Effect of adherent bacteria and bacterial extracellular polymers upon assimilation by Macoma balthica of sediment-bound Cd, Zn and Ag
Effects of adherent bacteria and bacterial extracellular polymer (exopolymer) upon uptake of particle-bound Cd, Zn and Ag by the deposit-feeding clam Macoma balthica were studied in the laboratory. Amorphous iron oxyhydroxide and unaltered and alkaline-extracted sediments were used as model particulates in separate, controlled deposit-feeding experiments. In general, amounts of metal taken up from
Authors
Ronald W. Harvey, Samuel N. Luoma
Remote sensing of tidal chlorophyll-a variations in estuaries
Simultaneous acquisition of surface chlorophyll-a concentrations for 39 samples from boats and Daedalus 1260 Multispectral Scanner data from a U-2 aircraft was conducted in the northern reaches of San Francisco Bay on 28 August 1980. These data were used to develop regression models for predicting surface chlorophyll-a concentrations over the study area for ebb-tide (8.40 a.m. P.D.T. (Pacific Dayl
Authors
Glenn P. Catts, Siamak Khorram, James E. Cloern, Allen W. Knight, Stephen D. Degloria
Field determination of the three-dimensional hydraulic conductivity tensor of anisotropic media: 2. Methodology and application to fractured rocks
The analytical solutions developed in the first paper can be used to interpret the results of cross-hole tests conducted in anisotropic porous or fractured media. In the particular case where the injection and monitoring intervals are short relative to the distance between them, the test results can be analyzed graphically. From the transient variation of hydraulic head in a given monitoring inter
Authors
Paul A. Hsieh, Shlomo P. Neuman, Gary K. Stiles, Eugene S. Simpson
Temporal fluctuations in grain size, organic materials and iron concentrations in intertidal surface sediment of San Francisco Bay
The physical and chemical characteristics of the oxidized surface sediment in an estuary fluctuate temporally in response to physical forces and apparently-fluctuating inputs. These characteristics, which include grain size and concentrations of organic materials and iron, will influence both trace-metal geochemistry and bioavailability. Temporal trends in the abundance of fine particles, total or
Authors
E. A. Thomson-Becker, Samuel N. Luoma
Separation of solute and particulate vectors of heavy metal uptake in controlled suspension-feeding experiments with Macoma balthica
Radioisotope labelling experiments with the estuarine clam, Macoma balthica, are described, in which a filter chamber device was used to separate solute metal uptake from uptake, of metals associated with suspended bacteria. Solute uptake contributed a majority of the 14-day total body burdens of 65Zn and 109Cd, whereas 57Co uptake largely resulted from ingestion of isotope-laden bacteria. In cont
Authors
Ronald W. Harvey, Samuel N. Luoma
Statistical evaluation of an inductively coupled plasma atomic emission spectrometric method for routine water quality testing
In an interlaboratory test, inductively coupled plasma atomic emission spectrometry (ICP-AES) was compared with flame atomic absorption spectrometry and molecular absorption spectrophotometry for the determination of 17 major and trace elements in 100 filtered natural water samples. No unacceptable biases were detected. The analysis precision of ICP-AES was found to be equal to or better than alte
Authors
J.R. Garbarino, B. E. Jones, G.P. Stein
Reduction of hexavalent chromium in water samples acidified for preservation
Reduction of hexavalent chromium, Cr(VI), in water samples, preserved by standard techniques, was investigated. The standard preservation technique for water samples that are to be analyzed for Cr(VI) consists of filtration through a 0.45‐µm membrane, acidification to a pH < 2, and storage in plastic bottles. Batch experiments were conducted to evaluate the effect of H+ concentration, NO2, tempera
Authors
Kenneth G. Stollenwerk, D.B. Grove
Error bounds in cascading regressions
Cascading regressions is a technique for predicting a value of a dependent variable when no paired measurements exist to perform a standard regression analysis. Biases in coefficients of a cascaded-regression line as well as error variance of points about the line are functions of the correlation coefficient between dependent and independent variables. Although this correlation cannot be computed
Authors
M.R. Karlinger, B.M. Troutman
Thermodynamic stability of CoOOH and its coprecipitation with manganese
A precipitate of cobalt oxyhydroxides formed by bubbling oxygen through a dilute solution of Co(NO3)2 held at pH 9.0 and 25°C was aged for 23 months in contact with the original solution, with access to atmospheric oxygen. Co3O4 and CoOOH were identified in the precipitate by X-ray diffraction. Chemical equilibria involving these solids were evaluated by measurements of solution pH and Co2+ activi
Authors
J. D. Hem, C. E. Roberson, Carol J. Lind