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D.P. Schultz

Publications and source records attributed to D.P. Schultz.

13 recordsLinked to original sources
USGS1990

Environmental contaminant concentrations in biota from the lower Savannah River, Georgia and South Carolina

Planned harbor expansion and industrial developments may adversely affect the economically important aquatic resources of the lower Savannah River, including those at the Savannah National Wildlife Refuge. To establish the present level of chemical contamination in this system, we collected a total of 102 samples of nine species of fish and fiddler crabs (Uca pugilator) from eleven sites in the lower Savannah River and on the Savannah National Wildlife Refuge, and analyzed them for concentrations of organochlorine chemicals, aliphatic and aromatic petroleum hydrocarbons, and 13 elemental contaminants: aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, selenium, and zinc. Residues of DDT (mainly as DDE),trans-nonachlor, dieldrin, Aroclor? 1260, mirex, and petroleum hydrocarbons were common in fish from the lower Savannah River, but concentrations were below those warranting environmental concern. In general, the concentrations of elemental contaminants also were low; however, arsenic, cadmium, and chromium concentrations were elevated in fish from river stations near the city of Savannah, and lead was elevated in samples from the National Wildlife Refuge. Contamination of the lower Savannah River by organic and elemental contaminants, as indicated by concentrations in fishes and fiddler crabs, did not appear to pose a hazard.

Archives of Environmental Contamination and Toxico↗
USGS1983

Rapid method for measuring rotenone in water at piscicidal concentrations

A high‐performance liquid chromatography (HPLC) procedure that is rapid, specific, and sensitive (limit of detection <0.005 mg/liter) was developed for monitoring application and degradation rates of rotenone. For analysis, a water sample is buffered to pH 5 and injected through a Sep Pak(R) C 18 disposable cartridge. The cartridge adsorbs and retains the rotenone which then can be eluted quantitatively from the cartridge with a small volume of methanol. This step effectively concentrates the sample and provides sample cleanup. The methanol extract is analyzed directly by HPLC on an MCH 10 reverse‐phase column; methanol: Water (75:25, volume : Volume) is the mobile phase and flow rate is 1.5 ml/minute. The rotenone is detected by ultraviolet spectrophotometry at a wavelength of 295 nm.

Transactions of the American Fisheries Society↗
USGS1978

Rapid method for determining concentrations of Bayer 73 in water during lampricide treatments

Two simple, rapid, sensitive methods were developed for determining the concentration of the lampricide 2',5-dichloro-4'-nitrosalicylanilide (Bayer 73) in stream water. Bayer 73 was extracted from acidified water samples with chloroform and then hydrolyzed to 2-chloro-4-nitroaniline (CNA) with either acid or base. The CNA was diazotized with sodium nitrite, and an azo dye was formed with either N -( 1-naphthyl) ethylenediamine dihydrochloride (after acid hydrolysis) or 1-naphthol (after base hydrolysis). There was no interference from the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) in either method. Standard curves were prepared with untreated water to compensate for interfering substances that occurred naturally in some streams. The methods were sensitive to about 0.005 mg/L (ppm). Time required for analysis of a sample ranged from 25 min to 1 h.

Journal of the Fisheries Research Board of Canada↗
USGS1976

Antimycin: Uptake, distribution, and elimination in brown bullheads (Ictalurus nebulosus)

Radioactive antimycin was readily taken up in bile and tissues of brown bullheads ( Ictalurus nebulosus ) exposed to 0.045 μg/ml of 14 C-antimycin for as long as 48 h. Bile contained the most and blood the least radioactivity at all sampling periods. The highest concentration of 14 C-antimycin in muscle was 0.12 μg/g, after 12 h of exposure. The average amount of 14 C-antimycin per fish was 0.94 μg/g. The 14 C-antimycin concentration decreased with the elapse of time in the muscle and in samples of combined head, skin, and viscera. The concentration of l4 C-antimycin in the exposure solution decreased from 0.045 μg/ml to 0.015 μg/ml after 12 h and 0.010 μg/ml after 48 h. The initial half-life of 14 C-antimycin in the exposure solution was about 6.5 h. A second group of fish was exposed to 0.045 μg/ml of l4 C-antimycin for 48 h and then transferred to antimycin-free, flowing water for up to 96 h. The 14 C-activity decreased in muscle tissue from 0.11 μg/g to 0.05 μg/g in 96 h. Half-life of 14 C-antimycin was about 75 h in muscle and 61 h in the combined head, skin, and viscera.

Journal of the Fisheries Research Board of Canada↗