Bleach is relatively benign when ingested in small amounts, but large amounts can cause death. It can also cause serious damage if it makes contact with the eyes, and it can irritate skin.
Tiny amounts of bleach are often used to purify water for drinking when boiling is not possible. Bleach can be fatal in a large enough dose, but there are so few recorded cases of death due to bleach ingestion that it is difficult to establish exactly what that dosage is. Bleach also contains chlorine, which is very toxic in gas form. Bleach sold for household use is stabilized, but prolonged exposure to fumes should still be avoided.