Thalaron radiation

Thalaron is a type of radiation in the tertiary EM band with biogenic properties, able to consume organic matter at the subatomic level. Thalaron's unique properties allow its effective range to expand almost without limit, meaning that even a microscopic amount can be incredibly dangerous.

History and Use
Because of its lethality, thalaron research was banned in the Federation. For a long time, it was considered to be only theoretical, until 2379, when it was used by Shinzon of Remus as part of his plot to overthrow the Romulan Empire and conquer the Federation.

Thalaron was first used by Shinzon to assassinate the Romulan Senate, via a small generator planted by fellow conspirator, Senator Tal'aura. Delivered by means of a cascading biogenic pulse, the radiation affected everybody in the Senate chamber, turning their bodies into an ash-like substance which subsequently disintegrated. Shinzon later planned to use the Reman Warbird Scimitar, which was itself essentially a massive thalaron generator, to eliminate all life on Earth, thereby crippling the Federation. Shinzon was opposed by the crew of the USS Enterprise (NCC-1701-E), who engaged him in battle in the area of space known as the Bassen Rift. Attempting to prevent Shinzon from using the generator to kill the Enterprise crew, Captain Jean-Luc Picard boarded the Scimitar and engaged him in hand-to-hand combat. Picard ultimately defeated Shinzon, but not in time to deactivate the generator before Lieutenant Commander Data arrived and beamed Picard back to the Enterprise with an emergency transport unit. Firing a phaser into the generator only seconds before the targeting sequence was complete, Data destroyed the generator, causing the Scimitar to explode. 

Apocrypha

 * In the short story "Twilight's Wrath" in Tales of the Dominion War, Shinzon captures the thalaron radiation generator from a secret Tal Shiar research facility in the Romulan Neutral Zone, indicating that the Romulans were secretly pursuing thalaron research without the Federation's knowledge.
 * In the Star Trek: Destiny novel trilogy, Seven of Nine proposed a Thalaron weapon as an anti-Borg weapon, with Picard actually ordering Lieutenant Commander Geordi La Forge to begin construction of such a weapon as the Borg prepare for their final assault, but La Forge refuses, not wanting to dishonour Data's sacrifice by creating the weapon he died to destroy.
 * In Star Trek Online, a Reman resistance cell takes possession of thalaron weapons from a massive Romulan space station known as the Vault, planning to use them in their struggle to gain freedom from the Romulans. Thalaron weapons are also employed by the Romulans in the game, most notably in the Scimitar-class warships.

Thalaronstrahlung Radiation de thalaron