Malon

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The Malon are a Delta Quadrant people who although were warp capable, didn't possess advanced recycling technologies unlike many other galactic species. This meant all the toxic by-products (specifically theta radiation) of warp reaction (estimated at 6 billion iso-tonnes per day) had to be dumped by a vast waste-export industry. They often found USS Voyager to be a hindrance to their plans. The Supertanker Keta was a Malon ship. Other than shipbuilding and waste dumping, the only exports are smap crop and therhea grain. Controller Emck liked to dump in the Void but Voyager stopped him. (TNG novel: Q & A; VOY video game: Elite Force)