Potential allergens (such as iodine) or contaminants (algae, etc.) are to be avoided in the sodium chloride, water, or buffering ingredients.[1] Premanufactured dosages of salt water flushing solutions can be purchased, or the user can mix non-iodized 'kosher' salt, with or without a buffering agent such as sodium bicarbonate or baking soda. (Table salt frequently is iodized, while sea salt may contain algae or other contaminants.)