Maybe this video will help you out. Seems like they are toxic for consumption in large amounts but not so with just one.
In my cod liver oil capsule bottle, I found a small plastic package of " AGELESS oxygen absorber-with a warning... DO NOT EAT. DO NOT MICROWAVE ". What's is that about?
Both Rooster Cogburn and echooos echooos have correct answers.
Here's another "factoid":
Oxygen absorbers have revolutionized the way that dehydrated food is stored long-term. The presence of oxygen decreases the storage life of food and causes oxidative deterioration. Oxygen absorbers are small packets that contain an iron powder. These food-safe packets are made of a material that allows oxygen and moisture to enter but does not allow the iron powder to leak out. Oxygen Absorbers are safe to place on top of and be contact with food. They will not harm the food they are in contact with as they come in individual food-safe pouches.
The "Do not eat, Do not microwave" is a general answer for consumers of the final product who may think the packet is either part of the medicine or a playtoy.
Sort of like when you generally tell a child, "Don't play with knives."
Some kids are knife throwing experts, but others may just as likely end up in the emergency room.
Oxygen absorbers can also recognize as "busters" labeled with "Do not eat" which are the small packets made from paper, polyethylene and PET materials and available in different packaging size.
Oxygen absorber packets are filled with Iron powder, natural zeolite powder, water and salt in which iron powder is the basic component material proven quite effective.
According to the food standard, Our FDA approved oxygen scavengers are reduce 0% oxygen level surrounding packaging environment and they design in such a way that when they fully absorb oxygen, the color of absorber is changed bright pink to dark blue. This isolation indicates that this desiccant is fully absorbing oxygen from packaging and correctly working.