De or het stofemissie?

The correct Dutch article is:

de stofemissie

Rule Words ending in -tie and -sie: almost always de. See the rule

How to use stofemissie

the stofemissiede stofemissie
this stofemissiedeze stofemissie
that stofemissiedie stofemissie
our stofemissieonze stofemissie
your stofemissiejouw stofemissie
every stofemissieelke stofemissie
which stofemissie?welke stofemissie?
a big stofemissie / the big stofemissieeen grote stofemissie, de grote stofemissie

Dutch words ending in stofemissie

koolstofemissie

In compound words, the last part decides the article. See the rule