Answer:
Dry Mouth (Xerostomia)
Fungal Infection.
Gum Swelling (Gingival Overgrowth)
Inflammation of the Lining Inside of the Mouth (Mucositis)
Mouth Sores (Ulcers)
Taste Changes, Including Metallic Taste.
Tooth Decay.
Tooth Discoloration.
The list that is composed of substances that are widely used for many years without apparent ill effects is the GRAS. GRAS is an abbreviation for generally recognized as safe; it is an American food and drug adminstration designation where chemical or substance added to food is considered safe by experts, and therefore, it is exempted from the usual federal food, drug, and cosmetic Act.
I believe some are mushrooms
Probably smaller bodies of water, as less water will heat up and evaporate faster.