I'm looking for a science-fiction short story, probably written by either Isaac Asimov or Poul Anderson. (I was binging on short stories collections from these two authors around the same time, 5 to 10 years ago, and I'm pretty sure the story I'm looking for came from one of these books.)
I recall from this story that an alien species has met with humanity, but they originated from a very different kind of world. On their planet, life evolved in another direction, and is based on nitrogen and/or arsenic (I think, it might be something else), whereas Earth-like life is based on carbon and oxygen.
To this alien species, these elements are poison, pretty much like arsenic and nitrogen are poison to humans, and this information plays a role in the story: there is an attempted murder on an alien or a suspicion of murder attempt, maybe at a dinner party. Before that, the relationship between the two species seemed relatively okay.