Alternate timeline
(covers information from an alternate timeline)

Polaric ions were particles which could be used as a weapon or as a power source. They were extremely unstable, and could produce temporal effects.

Since the Chaltok IV disaster in 2268, research and use of polaric ions was prohibited in the Alpha and Beta Quadrants.

In an alternate timeline, when the Makull's species' planet in the Delta Quadrant was ravaged by an explosion, differentially-charged polaric ions were left over from the detonation. The crew of the USS Voyager at first thought it may have been the result of weaponized polaric ions, however, to Captain Janeway's horror, they discovered their society had attempted to use them as power source without taking into consideration the danger. In the prime timeline, after the temporal paradox which produced the explosion was averted, Voyager did not detect polaric ions because the explosion never occurred. (VOY: "Time and Again")