A chemical element with an atomic number of 64 and an atomic weight equivalent to 157.2, is called Gadolinium, represented by the symbol Gd, this chemical compound belongs to the group of lanthanides and its name honors the scientist from Sweden J. Gadolin, who naturally was the first to isolate gadolinium in a pure form since in nature it can only be found in the form of a salt with other elements.

This metal has a silvery white color, it is characterized by being totally ductile and malleable, its most common state is oxidized (Gd2O3) being strongly magnetic for iron when it has a low temperature, it is obtained mainly from monazite sand. This element can be used for the manufacture of control rods in nuclear reactors, due to its ample capacity to capture numerous neutrons of a thermal nature, however the ideal isotopes for this work are gadolinium 155, gadolinium 157 and these are not found in abundant quantities being the main reason that the controls do not have a lasting energy.

Another use that can be attached to this element is in the construction of microwaves, gadolinium in combination with ythyrium form garnets that, when irradiated by a beam of light, will emit rays with high thermal values. In the same way as the compounds of the same group, gadolinium can be used to make television screens. Gadolinium is also used for contrast body X-rays, this chemical compound, when injected intravenously, allows a better appreciation of the images when magnetic resonance imaging is performed, especially in the observation of areas such as: the gastrointestinal tract, blood vessels in general (arteries and veins), soft tissues such as muscles, fat and skin, brain tissue and mammary glands can also be observed.

Like all the lanthanide groups, the main organs that can be affected by this element are the respiratory system and internal tissues such as the liver. At an environmental level, it can mainly affect aquatic animals and produce conditions in the soil, which will lead to increase the concentration of this element in humans when it comes into contact with both environments.