Plasma

platelets

monocytes （MNC） and erythrocytes have been separated from the whole blood offered by 53 healthy students by using "PERCOLL" liquid. Twenty elements in the above four components

including twelve essential trace elements

have been measured by ICA- AES except Se which was determined by catalytic pulse polarography. A significant age difference of Mo and Se contained in plasma as well as Fe

Ni

Ca

Zn and Cu in MNC was found. The level of the above elements was higher in college- students than that in middle- school- students

while the level of Mn in middle- school- students was higher than that in college- students. For middle- school- students

the level of Ca and Cr in plasma was higher in males than that in females. For college- students

except for Ti

Si

Cd and Co in MNC

the level of all other elements was higher in females than that in males

but the level of P and Fe in erythrocytes was higher in males than that in females. There was no age and sex difference in platelets. A significant difference of elements levels in each component was found. The level of different elements in each MNC was higher than that in each platelete and erythrocyte. There was some correlation among elements in each component of blood.