Impaired excretion of uric acid, or its overproduction can lead to a condition known as "gout". Crystals of uric acid precipitate out into joints, causing a "gouty arthritis", and in the kidneys and ureters, causing stones and obstructions. Gout usually results from impaired excretion of uric acid due to various causes. Lead is known to impair uric acid excretion by the kidney and the incorrect historical association of gout with overeating is probably secondary to coexisting chronic lead poisoning that occurred when lead leached out into pewter drinking vessels used for wine consumption. This is believed, by some, to be one of the causes of the decline and fall of the Roman Empire. We will touch upon overproduction of uric acid shortly.