For example, are groundwater, rainwater and mineral water commodities?

Not a commodity. Commodities are products of labor exchange. Without labor operation, water in the natural state is not a commodity. So groundwater, rainwater and mineral water are not commodities. Water is an inorganic substance composed of hydrogen and oxygen, which is nontoxic and drinkable. At normal temperature and pressure, it is a colorless and odorless transparent liquid, which is called the source of human life and an important substance to maintain life, also called hydrogen oxide.