Publications

No abstract available.

No abstract available.

Nonpoint sources of pesticides are a national issue and are a major interest in the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program because of their potential toxicity to humans and aquatic life. Using the water-quality data collected by the Trinity River Basin NAWQA study-unit team, an analysis of pesticides in urban and agricultural streams was made by...

Trends are computed for nutrient inflows from 37 streams discharging into the Gulf of Mexico. The drainage areas of these streams represent about 86 percent of the drainage area to the Gulf from the conterminous United States. The period analyzed varies for each stream, but generally includes water years 1972-93. Stations included in this analysis primarily are part of the National...

Understanding the water budget of the Everglades system is crucial to the success of restoration and management strategies. Although the water budget is simple in concept, it is difficult to assess quantitatively. Models used to simulate changes in water levels and vegetation resulting from management strategies need to accurately simulate all components of the water budget. One of the...

Abstract not supplied at this time

Elevated concentrations of planar, halogenated hydrocarbons have been linked to reproductive problems in a variety of fish-eating birds and mammals in the Great Lakes and in particular Saginaw Bay. Currently, there are no accurate procedures to assess bioavailability of these contaminants. Polychlorinated dibenzo-p-dioxins and dibenzofurans and mono- and non-ortho-chloro-substituted...

Laboratory studies were conducted with five early life stages of rainbow trout, Oncorhynchus mykiss, to determine the acute toxicities of five fire-fighting chemical formulations in standardized soft and hard water. Eyed egg, embryo–larvae, swim-up fry, and 60- and 90-d posthatch juveniles were exposed to three fire retardants (Fire-Trol LCG-R, Fire-Trol GTS-R, and Phos-Chek D75-F) and...

Studies by Russian scientists have documented significant alterations and impairment of critical behavioral functions in aquatic organisms following exposure to environmental contaminants. Behavioral responses disrupted by sublethal exposure to toxicants are intimately involved in habitat selection, foraging, competition, predator-prey relationships, and reproduction, and are essential...

Abstract not supplied at this time

β-Adrenoceptors (βARs) and muscarinic cholinergic receptors were measured in brain, gill, and heart tissues of brown bullhead catfish exposed to polycyclic aromatic hydrocarbons in the Black River, Ohio, USA, and were compared to values from Old Woman Creek, Ohio, a reference site. A decreased number of βARs were found in the gill from Black River fish, possibly indicating a compensatory...

The significance of sediment contamination is often evaluated using sediment toxicity (bioassay) testing. There are relatively few “standardized” test methods for evaluating sediments. Popular sediment toxicity methods examine the extractable water (elutriate), interstitial water, or whole (bulk) sediment phases using test species spanning the aquatic food chain from bacteria to fish...