They seem very concerned about this.
Check it out:

The Department of Homeland Security is warning some flights to Russia to lookout for toothpaste and cosmetic tubes that could contain material to construct a bomb, an official confirmed.

The warning Wednesday, which DHS described as a “routine communication,” is going out to U.S. flights flying directly to Russia and some foreign flights, according to reports.

A DHS official released a statement saying it is not aware of a “specific threat to the homeland” at this time, and it regularly shares information with domestic and international partners.