Theta radiation

Theta radiation is an energy form which can be extremely toxic to humanoid life. A regular byproduct of antimatter waste, theta radiation in high enough concentrations can disrupt subspace and prevent the formation of a stable warp field. 

In the absence of proper precautions, theta radiation can be extremely hazardous. Symptoms of theta radiation poisoning included hallucinations, fatigue, and nausea. Over longer periods of time, cumulative exposure can cause cellular degradation and severely shorten life expectancy, and theta radiation of extremely high levels can liquefy organic material. 

By the 24th century, Starfleet had eliminated the generation of this form of waste product, utilizing a transkinetic chamber to break down the residual antimatter on a subatomic level, and a series of radiometric converters to absorb the resultant theta radiation, recycling the energy and using to power various ship's systems. 

In 2063, upon traveling back in time from the year 2373, the Borg attacked Zefram Cochrane's launch facility in Montana, damaging, among other things, the throttle assembly of Cochrane's warp vessel, the Phoenix, causing it to leak harmful theta radiation. This necessitated the inoculation of members of the crew of the USS Enterprise (NCC-1701-E), which had followed the Borg vessel from the future, against theta radiation poisoning. Cochrane's partner, Lily Sloane, herself succumbed to the effects of severe theta radiation poisoning, although she was successfully treated by Doctor Beverly Crusher, chief medical officer of the Enterprise. 

Theta radiation in small doses can be used to destroy microorganisms, and was used in the 's decontamination chamber when it was determined that a member of the crew was infected. In 2153, after exploring an uninhabited planet, Doctor Phlox discovered that he and Subcommander T'Pol had been infected with an unknown microorganism, and attempted to use theta radiation to eliminate the infection. 

Later that year, while attempting to synthesize trellium-D with which to insulate their hull against the effects of spatial anomalies, T'Pol and Commander Tucker attempted theta radiation bombardment. However, when the molecular pressure began to rise uncontrollably, Tucker deactivated the theta radiation, to no effect, eventually necessitating Tucker and T'Pol's evacuation of the lab in order to avoid the resultant explosion. 

In 2375, while traversing the Delta Quadrant, the crew of the USS Voyager encountered a region of space nearly 25,000 light years across, wherein no star systems existed, and all light from outside was occluded by heavy concentrations of theta radiation, resulting in a starless, oppressive expanse which the crew took to calling "the Void." The crew soon discovered that the theta radiation was a result of massive amounts of antimatter waste being dumped in the region by the crew of a Malon export vessel, despite the harmful effects it was having on at least one species native to the area. In an attempt at diplomacy, the Voyager crew offered to share their reclamation technology with Controller Emck, the master of the Malon vessel, although Emck ultimately chose to turn down their offer, as it would put him out of business. 

Later that year, the Voyager crew encountered another Malon vessel, while attempting to retrieve a multispatial probe which had become trapped in the atmosphere of a gas giant. The Malon, attempting to obtain the probe for themselves, released a cloud of theta radiation as a form of attack, successfully weakening Voyager's shields to 89 percent. 

Also that year, while attempting to narrow the possible events which could have been causing a ship-wide molecular decay, the biomimetic crew of a duplicate Voyager considered an encounter with a species known as the Kmada, who attempted to sabotage their life support system with theta radiation, although they ultimately rejected this as a possibility. 

Later in 2375, Voyager encountered a Malon vessel yet again, this time suffering from catastrophic damage, threatening to explode and spread over four trillion isotons of antimatter waste over an area of three light years. Utilizing an inoculation developed by The Doctor which temporarily prevented their cells from absorbing theta radiation (although Neelix swore by his recipe of crushed rama leaves and Katyllian cloves), a boarding party from Voyager attempted to repair the vessel, only to discover that the ship had been sabotaged by what the Malon referred to as a "vihaar," a former crewmember who had been severely poisoned and deformed by exposure to theta radiation.