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J.M. Galloway

Publications and source records attributed to J.M. Galloway.

3 recordsLinked to original sources

Pharmaceuticals and other organic chemicals in selected north-central and northwestern Arkansas streams

Recently, our attention has focused on the low level detection of many antibiotics, pharmaceuticals, and other organic chemicals in water resources. The limited studies available suggest that urban or rural streams receiving wastewater effluent are more susceptible to contamination. The purpose of this study was to evaluate the occurrence of antibiotics, pharmaceuticals, and other organic chemicals at 18 sites on seven selected streams in Arkansas, USA, during March, April, and August 2004. Water samples were collected upstream and downstream from the influence of effluent discharges in northwestern Arkansas and at one site on a relatively undeveloped stream in north-central Arkansas. At least one antibiotic, pharmaceutical, or other organic chemical was detected at all sites, except at Spavinaw Creek near Mayesville, Arkansas. The greatest number of detections was observed at Mud Creek downstream from an effluent discharge, including 31 pharmaceuticals and other organic chemicals. The detection of these chemicals occurred in higher frequency at sites downstream from effluent discharges compared to those sites upstream from effluent discharges; total chemical concentration was also greater downstream. Wastewater effluent discharge increased the concentrations of detergent metabolites, fire retardants, fragrances and flavors, and steroids in these streams. Antibiotics and associated degradation products were only found at two streams downstream from effluent discharges. Overall, 42 of the 108 chemicals targeted in this study were found in water samples from at least one site, and the most frequently detected organic chemicals included caffeine, phenol, para -cresol, and acetyl hexamethyl tetrahydro naphthalene (AHTN).

Journal of Environmental Quality

Water quality of two streams near Yellowstone Park, Wyoming, following the 1988 Clover-Mist wildfire

In 1988, wildfire burned over 50% of the Jones Creek watershed near Yellowstone Park, Wyoming. Crow Creek, an adjacent watershed, was unburned. Water quality data collected from 1989-1993 may show the fire's effect on weathering and nutrient transport. Jones Creek had 25-75% larger concentration of dissolved solids than Crow Creek during the sampling period. Both streams revealed molar ratios consistent with the stoichiometry of andesine and pyroxene hydrolysis in the trachyandesites that underlie the basins. During 1989, nitrate transported from the unburned Crow Creek basin peaked at 2 mmol ha-1 s-1. This was twice as much as Jones Creek, possibly indicating a source from ash fallout. By 1992 these rates diminished to 0.1 mmol ha-1 s-1 in Crow Creek and increased to 1.8 mmol ha-1 s-1 in Jones Creek, suggesting later nitrate mobilization in the burned watershed. Phosphorus transported from Jones Creek basin averaged 0.011 mmol ha-1 s-1 during summer 1989, but fell to 0.004 mg ha-1 s-1 in subsequent years.In 1988, wildfire burned over 50% of the Jones Creek watershed near Yellowstone Park, Wyoming. Crow Creek, an adjacent watershed, was unburned. Water quality data collected from 1989-1993 may show the fire's effect on weathering and nutrient transport. Jones Creek had 25-75% larger concentrations of dissolved solids than Crow Creek during the sampling period. Both streams revealed molar ratios consistent with the stoichiometry of andesine and pyroxene hydrolysis in the trachyandesites that underlie the basins. During 1989, nitrate transported from the unburned Crow Creek basin peaked at 2 mmol ha-1 s-1. This was twice as much as Jones Creek, possibly indicating a source from ash fallout. By 1992 these rates diminished to 0.1 mmol ha-1 s-1 in Crow Creek and increased to 1.8 mmol ha-1 s-1 in Jones Creek, suggesting later nitrate mobilization in the burned watershed. Phosphorus transported from Jones Creek basin averaged 0.011 mmol ha-1 s-1 during summer 1989, but fell to 0.004 mg ha-1 s-1 in subsequent years.

Environmental Geology