Before and during 2375, Emck had discovered a spatial vortex near the edge of an interstellar void. This vortex lead into the heart of the void, where there were no stars or planets. Emck used this region of space to dump his contaminated antimatter cargo loads from his homeworld. The location cut his expenses for transportation. He did not know that the theta radiation created by the contaminated antimatter was killing an alien species indigenous to the void.
When the USS Voyager traveled through the void, they met Emck when he used spatial charges to flee some aliens holding Voyager. The Voyager crew later found out (from one of the aliens) that Emck was dumping contaminated antimatter and tried to teach him ways so antimatter used by the Malon would not caused byproducts. Emck dismissed this, noting that he would lose his job, along with his crew. Attempting to use the spatial vortex in the void, Emck attempted to stop Voyager from destroying the vortex. With assistance by the Night Aliens, the Malon export vessel was destroyed and Emck was killed when the Night Aliens took down his ship's powerful shields, allowing Voyager to destroy it. (VOY: "Night")