Allergies & Infections
Many allergies can result in metallic taste. Infections such as fungal infection in mouth and tongue which affects the taste buds can also changes the taste of your mouth.
Inhaled Substances
Prolonged inhalation of some chemicals like benzene, hydrazine, gasoline, lacquers, rubber dust, cobalt, etc., can also result in metallic taste. People working in such industries usually face this problem.
Other Causes
Other causes of metal like taste in mouth may consists of Teeth Whitening Kit unfiltered underground water which contains traces of metals such as calcium and magnesium, leakage of metal from the dental filling, aging, etc. Excess smoking can also be a cause for this taste.

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