Does the suctioned fat used in a fat transfer procedures contain the any toxins that may be stored in fat cells?

I understand that the body can use fat cells to store excess estrogen, heavy metals, etc. that perhaps the liver cannot process if not functioning optimally/burdened. When this fat is put in another area - fat removed from hips or thighs and placed in face or breasts, does that fat contain any toxins that were there when it was suctioned? Is the suctioned fat processed to remove any toxins? If someone loses weight after having had fat transfers, what happens to the areas of transferred fat?