Exposure Pathways

This visualization tool helps researchers and public health officials see how relations between poultry density and waterfowl migration routes affect the threat of avian influenza to people and the poultry industry.

During the past two decades, great strides have been made toward the development and use of ecotoxicity testing methods that reduce animal use or replace animals altogether with in vitro tests or in silico models.

A riparian zone rich in terrestrial insects can provide an alternate food source for fish in metal-impacted watersheds.

The incidence of particular skin and liver tumors on white suckers collected from some Wisconsin rivers corresponded to the degree of urban development within the watershed. Further research is needed to understand the relationship between exposure to urban-sourced contaminants and the initiation, promotion, and potential for population-level effects of these tumors.

Changes in the regulation and use of some organic chemicals have caused environmental concentrations to stabilize or decline during the past 35 years coincident with a rebound in the osprey ( Pandion haliaetus) population of the Chesapeake Bay.

The unique combination of natural processes and human activities present in western North America can strongly affect the exposure of fish and birds to methylmercury, the most toxic form of mercury (Hg).

Tree swallow eggs at most study sites in the Great Lakes basin were minimally exposed to legacy organic contaminants and brominated flame retardants.

The first known hepatitis B virus to infect fish (white sucker; Catostomus commersonii) has been discovered by U.S. Geological Survey (USGS) scientists.

U.S. Geological Survey (USGS) scientists developed 129 sediment-toxicity benchmarks for use in evaluating currently used pesticides in whole sediment.

A recent study by the U.S. Geological Survey (USGS) provides some of the first environmental contaminants data for a species of passerine bird (perching birds) in Alaska but leaves unanswered questions as to the cause of beak abnormalities found in this species.Beginning in the late 1990s, biologists and members of the public reported an unusual number of beak abnormalities among black-capped...

Estrogens are recognized as modulators of immune responses in mammals, but how these effects might occur in fish was not understood. U.S. Geological Survey (USGS) scientists published findings that fish white blood cells (leukocytes) have specific estrogen receptors (ERs)—a discovery that moves scientists one step closer to understanding the connection between exposure to estrogenic substances and...

Scientists from the U.S. Geological Survey (USGS) are helping to track the movement of three strains of highly pathogenic avian influenza viruses (HPAIV) in wild birds. HPAI viruses are a concern as they are very pathogenic to poultry and some species of wild birds such as raptors. Infection can result in significant mortality of poultry and impact international trade of poultry products. In...