By Laura Zuckerman

Sat May 10, 2014 2:00am EDT

(Reuters) - A New Mexico nuclear waste dump, which saw a radiation leak in February, has halted shipments of toxic waste barrels to a commercial Texas facility amid concerns that chemical reactions could trigger another release there, officials said on Friday.

A probe found the February 14 accident may have been linked to improperly prepared and packaged drums of toxic waste accepted from the Los Alamos National Laboratory by the Waste Isolation Pilot Plant (WIPP), its managers said in a statement.

Investigators are still evaluating whether a chemical reaction caused the leak of unsafe concentrations of radiation in the underground salt caverns where waste is stored, which exposed 21 workers above ground to low levels of contamination.

"As they evaluate this possibility, it is prudent to temporarily stop shipments of this specific (Los Alamos lab) waste stream" to a commercial storage facility in Texas, managers said.

REUTERS