Joseph Enterprises has never sought FDA approval for Chia Pets and Chia Heads, and therefore cannot promote them as a food product. Chia seeds are sold in health food stores, however, and many organic gardens harvest them for salads and sandwiches. Joseph Enterprises' Chia seeds are not treated with any chemicals or fertilizers. My cat ate the sprouts.
Many cats eat greens when they have an upset stomach, in order to induce vomiting.
Keep in mind that your cat may be eating the Chia sprouts because it already ingested something poisonous, and wants to throw up. Or it might just like to nibble on grassy stuff. Use your judgment, and when in doubt, call a veterinarian. My Chia Pet is leaking. Some seepage into the drip tray is to be expected.