Multimedia

This animation of the biogeochemical nitrogen cycle illustrates the main steps of the cycle in air, water, and soils. The video explains and connects the many forms of nitrogen, such as ammonia, ammonium, hydroxylamine, nitrite, nitrate, nitrous oxide, and nitrogen dioxide, and explains the role of nitrate in nitric oxide signaling in the human body.

This animation of the biogeochemical nitrogen cycle illustrates the main steps of the cycle in air, water, and soils. The video explains and connects the many forms of nitrogen, such as ammonia, ammonium, hydroxylamine, nitrite, nitrate, nitrous oxide, and nitrogen dioxide, and explains the role of nitrate in nitric oxide signaling in the human body.

Juvenile Coho salmon (Oncorhynchus kisutch) exhibiting abnormal behaviors associated with exposure to 6PPD-quinone, a derivative of the compound 6PPD which is used in tires to prevent wear.

The U.S. Geological Survey laboratory for the analysis of per- and polyfluoroalkyl substances (PFAS) uses cutting-edge techniques to analyze environmental samples including tissues, plasma, water, and soils to undertake and support research projects across the country.

Webinar on USGS research findings on Polycyclic Aromatic Hydrocarbons (PAH) contamination associated with coal-tar-based sealants and implications for environmental and human health. Dr.

Congressional Briefing at the Capitol Visitors Center on April 11, 2014. The briefing focuses on the Mississippi River Basin, which covers about 40% of the nation and represents a wide range of important climatic, agricultural, and urban influences that are present throughout the country.