DENVER -- A vial with about a 1/4 gram of powder containing plutonium cracked and spilled radioactive particles in a lab, exposing 22 workers at the National Institute of Standards and Technology to trace contamination.

Two workers, who had worked directly with the radioactive material Monday, got rid of the contamination by washing their hands. NIST officials said most of the 20 other nearby workers had trace contamination on their shoes and clothing, which was washed off.

Workers were using the plutonium containing powder for a project to improve radiation detectors for use by nuclear inspectors. The lab has been sealed off.

An NIST spokesman on Tuesday said the incident has been reported to the Nuclear Regulatory Commission. Congressman Mark Udall (D-Eldorado Springs) released a statement saying:

"NIST has assured me that the scientists in the lab are fine and that there is no contamination outside of the one impacted lab, but yesterday’s incident at NIST’s Boulder labs is still a matter of deep concern. I am looking into exactly how this problem occurred and what can be done to prevent similar incidents in the future. As a Member of the Science and Technology Committee, I will continue to work closely with NIST to ensure that they are doing everything they can to protect their staff as well as the entire Boulder community."