Selenious acid or hydrogen selenide about which we have just talked, is very caustic when ingested. Fatalities from accidental ingestion of gun bluing agents are however possible. But just now you said that hydrogen selenide has garlicky odor. I only said that in selenium poisoning one has garlicky odor. Let me tell you how these two statements are compatible.
Garlicky odor is actually due to the excretion of dimethyl selenide in the breath.
In the body, various selenium compounds can actually get converted to this compound to give rise to garlicky odor. So although selenious acid is odorless in itself, it can give rise to garlicky breath. But it was due to his having examined a selenium deposit in a sulphuric acid chamber. He had inhaled fumes which were probably those of dimethyl selenide. Oh, that is indeed very interesting doctor.