Is it wrong to discard ordinary light bulbs in trash?

Somebody told me today that light bulbs, like batteries and motor oil, should not be thrown away in your regular trash can or dumpster, perhaps for ecological reasons. Is this so? Heck, a light bulb only consists of glass, argon, and the metal (s) in the base.

If by “ordinary” you mean incandescent, then it is perfectly fine to throw those out in regular trash.
Halogen and LEDs are safe as well.

Fluorescent and compact fluorescent bulbs contain mercury which can leak into the groundwater and need to disposed of some other way.

Do LEDs contain arsenic or other toxic metals?

Light bulbs - Yes, ordinary incandescents go into the trash. AFAIK, no municipalities accept them in a home recycling bin.

Regular and compact fluorescents shouldn’t go to the trash or recycle bin. All Home Depot stores accept CFLs for recycling, and it wouldn’t surprise me if other chains like Ace, Lowes and Menards also accept them.

LEDs - Yes, they do contain heavy metals like gallium and arsenic, but in microscopic and reasonably inert forms. Unless you grind LED emitters or chips into dust, the materials aren’t overtly poisonous.

Lowe’s recycles CFLs too.

As does Menards. I don’t know about Ace. The one in my parent’s town apparently charges a dollar, the ratfinks, but strictly speaking I’m not sure if it’s still an Ace.