Contact Us to ask a question, provide feedback, or report a problem.
Last updated on November 18, 2024
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Sources of lead emissions vary from from place to place, with highest air concentrations of lead usually found near lead smelters.