Depending on the person, and the intake amount of course. But this can vary in many ways
Treating a person's mental disorders will reduce suicide risk.
All of the other options can be dangerous for those suffering from depression or who are suicidal.
Oxygen in the air can cause sliced fruit to brown, a process called enzymic browning (an oxidation reaction). Phenols and the enzyme phenolase are found in the cells of the apple, and when these are exposed to oxygen in the air, for example through slicing, the oxygen causes a reaction.
