Detect Poison

(Player's Handbook v.3.5, page 219, DnD 3.5)

Divination

Level: ; Cleric 0; Druid 0; Paladin 1; Ranger 1; Sorcerer/Wizard 0; Healer 0; Blighter 0; Death Delver 1; Nentyar Hunter 1; Wu Jen 0; Sha'ir 0; Death Master 0; Urban Druid 0; Assassin 1; Court Herald 0
Components: V, S
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One creature, one object, or a 5-ft. cube
Duration: Instantaneous
Saving Throw: None
Spell Resistance: No

You determine whether a creature, object, or area has been poisoned or is poisonous.
You can determine the exact type of poison with a DC 20 Wisdom check.
A character with the Craft (alchemy) skill may try a DC 20 Craft (alchemy) check if the Wisdom check fails, or may try the Craft (alchemy) check prior to the Wisdom check.
The spell can penetrate barriers, but 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt blocks it.