Which component of the interstellar medium is described as being subject to destruction over cosmic timescales, requiring replenishment from supernovae?

Answer

Dust grains

Dust grains are micron-sized and are subject to sputtering and destruction over long timescales, meaning they must be constantly replenished, often through supernovae explosions.

Which component of the interstellar medium is described as being subject to destruction over cosmic timescales, requiring replenishment from supernovae?
galaxyastronomyspiral galaxygasdust