Mike, I haven't a dog in this hunt---just a lot of curiosity.
"Again, what about urban pigeons having a higher lead content than rural pigeons? Where are they ingesting lead shot."
Wouldn't urban pigeons be exposed to more lead from exhaust emissions?
I don't know.
I do know in cities there are:
Smelters, both abandoned and operating (ASARCO closed a smelter 1-1/2 miles north of my house about four decades ago.
Lead battery factories, both abandoned and operating
Gangs shooting lead bullets.
Water towers with lead paint on them. A few years ago they stripped the lead paint off of a water tower 1/4 mile from my house. A windstorm came, blew away the tarps, and little chips of blue paint could be found swirling in the wind in the parking lot at my office.
I am pretty sure there is lead based paint on the outside of my house, built in 1923.
I am pretty sure there is lead based paint on the inside of my house.
I grew up in a plumbing company and we used to make lead joints in cast iron drainage, waste, and vent pipes.
We also made lead drum trap fittings and wiped lead for the plumbing under the kitchen sink upon occasion.
We used to use a lead flashing where the sewer vent piping penetrated the roof.
A lead shower pan in the bottom of the shower and below the tile used to be universal.
Until a few years ago all copper water piping was soldered with lead solder. It is almost a sure thing that the copper water piping in my house is soldered with lead solder.
Until a few years ago the kitchen sink faucets in my house had lead in the metal used to make them. They wore out and the new ones are required by law to have no lead.
So you tell me where the lead in those urban pigeons came from?
Add mining and lead shot to this list and you can pretty much use the same list to determine where lead in grouse livers is coming from.
And if you eliminate one of the urban sources of lead will the the lead levels go down in urban pigeons?
And though lead in gas is now outlawed (except aviation gas) certainly there is residual lead everywhere automobiles went.
Best,
Mike
