Even though lead usage has declined due to environmental
awareness and regulation, several human sources of lead continue
to affect birds. Hunting ammunition and fishing gear are
ingested by the birds, with toxic effects. Homepage for the
research on occurrence, movement, flux, fate, and effects of
agricultural chemicals, such as pesticides, in 25 states by the
Midcontinent Agricultural Chemical Research Project (MACRP) with
links to study results and publications. Multiple studies
addressing urban water-quality issues, to describe biological,
chemical, and physical characteristics of urban water resources
over time, and relate those characteristics to natural processes
and human activities Primary homepage for the National Water
Quality Assessment (NAWQA) Program studying water quality in
river, aquifer and coastal water basins throughout the nation.
Links to reports, data, models, maps and national synthesis
studies. Trace elements are inorganic chemicals occurring in
small amounts in nature. This web site