The World Health Organization considers mercury to be “highly toxic to human health.” If the element is inhaled or ingested it may be detrimental to a variety of organ systems; these include the immune, digestive and nervous systems. Minor indications of poisoning include headaches, weakness, and a continuous bitter taste in the mouth. Because it does affect individuals neurologically, mercury is sometimes referred to as a neurotoxin. Mainly damage is done to the cerebellum, which is responsible for motor control (coordination, balance). Those affected typically display signs of stumbling, tremors and difficult speaking and/or swallowing. The inorganic salts that form are able to breakdown cellular components of the skin, eyes and gastrointestinal tract. Most of these damages, especially neurological, that humans experience are permanent.