Caesium (cesium in USA) has no biological role. However it is capable of replacing potassium in the body to some extent because of its chemical similarity. Ingestion of any caesium compounds is therefore to be avoided. Because of this similarity, the isotopes¹³⁴Cs and¹³⁷Cs (present in the biosphere in small amounts as a result of radiation leaks) are very toxic. Rats fed caesium in place of potassium in their diet die.

Levels in humans

Theabundances of the elements in humans.

• Human abundance by weight: 20 ppb by weight
• Human abundance by atoms: 1 atoms relative to C = 1000000

How much caesium is in your body? Find out here.

You can use this form to calculate how much caesium your body contains. Enter your weight in either kilograms or pounds and click the "Calculate" button. You must enter a number, not text!Elements for which there are no data will always give a value of zero for the weight, no matter what you put in the weight box.

Hazards and Risks

Hazards and risks associated with caesium:

Caesium (cesium in USA) compounds are encountered rarely by most people. All caesium compounds should be regarded as toxic because of its chemical similarity to potassium. Because of this similarity, the isotopes¹³⁴Cs and¹³⁷Cs (present in the biosphere in small amounts as a result of radiation leaks) are very toxic. Rats fed caesium in place of potassium in their diet die. Large amounts cause hyperirritability and spasms.

References

• J.E. Huheey, E.A. Keiter, and R.L. Keiter inInorganic Chemistry : Principles of Structure and Reactivity, 4th edition, HarperCollins, New York, USA, 1993.
• S. Budavari (Ed.) inThe Merck Index, 11th ed., Merck, USA, 1989.
• N.N. Greenwood and A. Earnshaw inChemistry of the Elements, 2nd edition, Butterworth, UK, 1997.