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Publications

Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 4098

Pyrolysis-mass spectrometry/pattern recognition on a well-characterized suite of humic samples Pyrolysis-mass spectrometry/pattern recognition on a well-characterized suite of humic samples

A suite of well-characterized humic and fulvic acids of freshwater, soil and plant origin was subjected to pyrolysis-mass spectrometry and the resulting data were analyzed by pattern recognition and factor analysis. A factor analysis plot of the data shows that the humic acids and fulvic acids can be segregated into two distinct classes. Carbohydrate and phenolic components are more...
Authors
P. MacCarthy, S.J. DeLuca, K.J. Voorhees, Ronald L. Malcolm, E.M. Thurman

Statistical evaluation of an inductively coupled plasma atomic emission spectrometric method for routine water quality testing 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...
Authors
J.R. Garbarino, B. E. Jones, G.P. Stein

Error bounds in cascading regressions 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...
Authors
M.R. Karlinger, B.M. Troutman

Thermodynamic stability of CoOOH and its coprecipitation with manganese 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...
Authors
J.D. Hem, C. E. Roberson, Carol J. Lind

Temporal fluctuations of silver, copper and zinc in the bivalve Macoma balthica at five stations in South San Francisco Bay Temporal fluctuations of silver, copper and zinc in the bivalve Macoma balthica at five stations in South San Francisco Bay

Concentrations of Cu, Ag and Zn were measured in the soft tissues of the estuarine bivalve Macoma balthica in South San Francisco Bay at near-monthly intervals for periods of two to three years at four stations, and eight years at a metal-enriched station. The amplitude and frequency of fluctuations differed among stations and among metals. Fluctuations were greatest at stations with the...
Authors
Samuel N. Luoma, Daniel Cain, C. Johansson

Geochemistry of Great Salt Lake, Utah I: Hydrochemistry since 1850 Geochemistry of Great Salt Lake, Utah I: Hydrochemistry since 1850

The hydrochemistry of Great Salt Lake, Utah, has been defined for the historic period, 1850 through 1982, from published data combined with new observations. The water balance depends largely on river inflow, atmospheric precipitation onto the lake surface and evaporation. Input of the major solutes can best be accounted for by mixing dilute calcium-bicarbonate type river waters with...
Authors
R. J. Spencer, H.P. Eugster, B.F. Jones, S.L. Rettig

Geochemical mass-balance relationships for selected ions in precipitation and stream water, Catoctin Mountains, Maryland Geochemical mass-balance relationships for selected ions in precipitation and stream water, Catoctin Mountains, Maryland

Results of a study of input/output mass balances for major ions based on the chemical composition of precipitation and stream-water, geochemical reactions with different loading rates of hydrogen ion, and watershed processes influencing the chemical character of stream-waters in two small watershed areas are reported with a view to predicting the effect of additions of acidic rain to the...
Authors
B. G. Katz, O.P. Bricker, M.M. Kennedy

Mechanistic roles of soil humus and minerals in the sorption of nonionic organic compounds from aqueous and organic solutions Mechanistic roles of soil humus and minerals in the sorption of nonionic organic compounds from aqueous and organic solutions

Mechanistic roles of soil humus and soil minerals and their contributions to soil sorption of nonionic organic compounds from aqueous and organic solutions are illustrated. Parathion and lindane are used as model solutes on two soils that differ greatly in their humic and mineral contents. In aqueous systems, observed sorptive characteristics suggest that solute partitioning into the...
Authors
C. T. Chiou, T.D. Shoup, P.E. Porter
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