The naturally occurring levels of barium in the environment are very low. High amounts of barium may only be found in soils and in food, such as nuts, seaweed, fish and certain plants. The amount of barium that is detected in food and water usually is not high enough to become a health concern.
People with the greatest risk to barium exposure with additional health effects are those that work in the barium industry. Most of the health risks that they can undergo are caused by breathing in air that contains barium sulphate or barium carbonate.

Many hazardous waste sites contain certain amounts of barium. People that live near them may be exposed to harmful levels. The exposure will than be caused by breathing dust, eating soil or plants, or drinking water that is polluted with barium. Skin contact may also occur.

The health effects of barium depend upon the water-solubility of the compounds. Barium compounds that dissolve in water can be harmful to human health. The uptake of very large amounts of barium that are water-soluble may cause paralyses and in some cases even death.

Small amounts of water-soluble barium may cause a person to experience breathing difficulties, increased blood pressures, heart rhythm changes, stomach irritation, muscle weakness, changes in nerve reflexes, swelling of brains and liver, kidney and heart damage.

Barium has not shown to cause cancer with humans. There is no proof that barium can cause infertility or birth defects.

Barium toxicity from food, however, has not been recorded.