Star Trek: 10 Species Who Need To Get With The Times

Malon society is incredibly dystopian. Unlike most warp-capable species, they do not recycle the anti-matter waste created by their industries. Because of this, Malon space is extremely polluted with theta radiation. Entire industries were created to transport this waste away from Malon Prime, and they would often dump it in inhabited areas, poisoning the local population.

Janeway offered a Malon waste exporter the recycling technology, and he denied her, explaining that this technology would destroy his business. Clearly, many Malon were economically incentivised to maintain the status quo.

Transporting and dumping anti-matter waste across space not only poisons vast regions of space, but also the Malon crew aboard these ships. They would often develop sores and other health problems from routinely being around toxic substances.

It's clear that Malon society could easily change its ways by developing cleaner technology (like the rest of the galaxy uses), but many of them have a profit incentive to keep the waste export ships running.