They can splinter and cause serious injury. Instead, give your cat a treat intended specifically for cats. Ask your veterinarian for recommendations, or ask a salesperson at your pet supply store. As a precaution, keep your garbage can secure from cats' access. Keep them locked up.
Inquisitive animals can suffocate.
Cats can jump to amazing heights. And always use a fireplace screen. But excessive heat can dry out their skin, and some cats even get burned without realizing it. Keep hot areas covered or off limits to your cat if possible. Watch out for cigarette butts, rubber bands, balloons, sewing needles, thread, string, ribbons and even pantyhose.