I was surprised last week when I found that barium sulfate for oral suspension is presently in short supply, and, therefore, we were unable to schedule an upper GI series for one of our patients.

It seems that there is a decrease in worldwide production of barium.

Barium is a chemical element with an atomic weight of 56 meaning that it has 56 protons in its nucleus.

This soft alkaline earth metal is highly reactive and therefore not found as a free element. It reacts with water to release hydrogen gas. The name “barium” is derived from a Greek word meaning” heavy.”

Barium sulfate “mud” is sometimes pumped down oil wells because its density helps to float rock fragments out the hole and to the surface.

Barium sulfate is X-ray opaque and used for upper and lower gastrointestinal X-ray studies.

If barium is swallowed, it will follow the path of the esophagus, stomach and small intestine, helping the radiologist to evaluate the upper GI tract. Naturally a barium enema is an entirely different type of examination helpful in evaluating the colon or large intestine.

The most common types of naturally occurring barium are barium sulfate or barite and barium carbonate or witherite. China has accounted for about 50 percent of the world’s production of barium, but, because of increased safety regulations in Chinese mines that production is now down to only 25 percent of prior volumes. Perhaps because of global depletion of the earth’s barite stores and the need for deeper mines, there is decreased production of barium. India contributes to about 15 percent of the world’s production of barium, and the USA and Morocco each about 8 percent.

So it appears that, at least for now, barium sulfate for upper GI studies is on back order, and a release date can not be determined. Radiology departments have noticed a shortage since last fall, and now the CSRA is feeling the barium “crunch.”

By the way, barium is added to fireworks to impart a green color upon explosion.

David Keisler is a gastroenterologist and internist in Aiken.