ST. LOUIS (AP) - A study by the U.S. Geological Survey is raising concerns after toxic levels of lead were found in songbirds in lead mining areas of Missouri.
USGS officials announced the survey results on Tuesday.
Lead mining and smelting has been going on in portions of southeast Missouri since the early 1700s. USGS captured 34 songbirds in the region known as the Old Lead Belt, part of the Big River flood plain and an area within the Mark Twain National Forest.
Tested birds had eight times the normal amount of lead in their blood, 23 times the normal amount in their kidneys. Lead poisoning in birds can cause abnormal muscle function, kidney and liver failure, decreased fertility and anemia.
Elevated lead levels were also found in soil and earthworms in the region.