Blood ph may become unbalanced if the rate of breathing is too fast or too slow.
If someone is hyperventilating hyperventilation is caused by breathing too deeply, too fast.
Blood ph may become unbalanced if someone is hyperventilating.
Blood pH may become unbalanced if someone is 
1. digesting
2. They may not survive.
3. hyperventilating
4. smoking tobacco
5. sleeping
6. sweating
7. major threat to health
8. consuming