Many ordinary things are poisonous or toxic for parrots. These include:
Common foods such as avocado and chocolate
Metals such as zinc and galvanized metal, common in inexpensive bird toys and cages
Keep your bird safe! Know the dangers, and learn how to keep toxic things out of the parrot's world.
Many common foods are toxic or poisonous to birds including: avocado, chocolate, salt, apple seeds, fruit pits, alcohol, mushrooms, tomato stems and leaves, tobacco products, onions, uncooked beans, and sugar.
Here are some useful links with more details:
Many seemingly harmless things are extremely toxic to birds including: non-stick or teflon coated materials (often found in cookware, toaster ovens, hair dryers, space heaters. etc),metals such as zinc, copper or lead (cause heavy metal poisoning), common household plants, and chemicals.
Here are some links with detailed information and explanations: