Slightly different post this week- I recently did a school project on the uses of Barium Sulfate within medicine. I have cited the sources below incase you would like to do some further reading.
Barium sulfate is an odorless, insoluble white powder used in order to ingest and then for it to be used as a contrasting agent in X-raying the digestive tract. It is also used in various manufacturing applications and mixed into heavy concrete to serve as a radiation shield.  Barium is a heavy metal, it’s a water-soluble element and highly toxic. 
Unlike visual light, x rays pass straight through objects. Which is not useful for viewing organs in the body, as organs and tissues are a lot less dense than bones thus they do not show us on x rays as the rays pass straight through.  Therefore we use an artificial contrast called barium sulfate.
As Barium sulfate is ingested, it is extremely useful for investigating the digestive tract.  Barium ions are opaque to X- rays and can absorb X-rays more strongly than other compounds. In order to produce the liquid suspension of Barium sulfate that is given to the patients to ingest, water is added to the powder. The patients will be asked to drink the liquid before the test; barium molecules will go through the digestive system and cover all the lining of the system, that procedure is called barium meal. When air is introduced to expand the gut after the meal has been ingested, really detailed pictures of the bowel lining can be produced, using the thin layer of barium. Small tumors and ulcers can be diagnosed in this way. Whilst the liquid flows through the digestive system, X-Rays will be taken, and the shapes of the coated organs can be clearly seen, to look for problems in the digestive system. 
Barium is only highly toxic if it is in a water soluble salt. Barium sulfate is ok to use as it is insoluble in water meaning it forms a suspension not a solution in water. If it forms a solution it wouldn’t be useable as it would be absorbed into the body which leads to barium poisoning. Barium poisoning can cause vomiting, colic, diarrhoea, tremors and paralysis. 
Common side effects of ingesting Barium sulfate include: bloating, constipation, nausea and vomiting, tightness in the chest and troubled breathing. 
To conclude, Barium Sulfate is incredibly important in medicine as it is the only way that that digestive system can be examined medically without invasive surgeries. It only has few minor side effects however it is to be used with caution due to the risk of barium poisoning which can be extremely dangerous for the patient.
Harvard Catalyst Barium Sulfate”. Harvard Catalyst. N.p., 2017. Web. 29 Apr. 2017.
Barium Sulfate Used In X-Rays. prezi.com. N.p., 2017. Web. 29 Apr. 2017.
YMCICHEM – B- Why Is Barium Sulfate Safe To Use For X-Rays Of The Digestive System Even Though Barium Ions Are Poisonous?. Ymcichem.wikispaces.com. N.p., 2017. Web. 29 Apr. 2017.
”Barium”. Education in Chemistry. N.p., 2017. Web. 29 Apr. 2017.
 Barium Sulfate Side Effects In Detail – Drugs.Com”. Drugs.com. N.p., 2017. Web. 29 Apr. 2017.