Invidium

A polarity scanner reveals the presence of Invidium

Invidium is an element with many uses, although it is also very dangerous if handled inappropriately.

For some years prior to 2366, the Federation had used invidium in its medical stasis fields, although this changed with the advent of newer and safer technology.

In 2366, the USS Enterprise-D was transporting a shipment from the Mikulaks when Reginald Barclay broke a container. Although it was contaminated, and removed, the container contained invidium. The substance then began wreaking havoc on ships systems, including causing the Replicators to malfunction. One other side effect was that it caused a drinking glass to melt in the hand of its holder, Lieutenant junior grade Duffy, releasing the beverage from within.

The engineering team realized the Mikulaks still used invidium, and took appropriate measures to repair the damage – Barclay stated that invidium became inert at -200° C, and the crew lowered the temperature of the affected systems to that temperature in order to render the element harmless. Afterwards, they went to Starbase 121 to decontaminate the ship. (TNG: "Hollow Pursuits")

A chapter in the Star Trek: The Starfleet Survival Guide, a non-canon, but basically screen-based guide has a chapter on "Detecting and Counteracting Invidium Contamination."

Furthermore, along with Jakmanite, Saltzgadum, Selgninaem and Lucrovexitrin, it is one of only five undetectable substances that can exist in a nitrogen-oxygen atmosphere and can alter the molecular structure of glass.

The subatomic structure of Invidium