The adult bald eagle was discovered near a Maryland highway, disoriented and not able to walk.

The team of wildlife rescuers at City Wildlife suspected lead poisoning.

Paula Goldberg is the executive director.

“This is our national bird," said Goldberg. “This is the symbol of our freedom. This bird is treasured by everyone who lives in the United States of America."

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City wildlife provides medical care and rehab to wild animals that have had nasty brushes with their urban habitat.

The facility can test for lead poisoning on the spot.

"This little unit can test a drop of blood for a lead level and give us a level within three minutes," aid Goldberg.

The blood test showed moderate poisoning, but enough to kill.

The bird died sometime during the night Wednesday.

Goldberg said the bird probably ate its lead with dinner, either from a lead slug left by a hunter or a sinker used in fishing.

“It’s so sad when a bird like this dies, because this may have been a preventable cause of death," said Goldberg.

Eagles aren’t the only birds in the area who come into contact with lead, city pigeons pick it up in dust near demolition sites.

“The only bright spot in this, if there is one, is that if this bird was mated, that its mate has enough time in the season to find another mate and to live happily ever after," said Golberg.

Times have changed: lead slugs are now illegal. And a push is on to replace the old sinkers with non-toxic versions.

After decades of use, those old poisons are often still out there for animals to find.

In accordance with federal law, the eagle’s remains were sent to the National Eagle Repository in Colorado to be examined and cataloged for research.