What organ experiences excess uptake due to high levels of aluminum in a 99mTc-sulfur colloid preparation?

In the context of a 99mTc-sulfur colloid preparation, the organ that experiences excess uptake due to high levels of aluminum is the lungs. Aluminum contamination can lead to an increased deposition of the sulfur colloid in the lungs, which is particularly problematic in imaging studies. When aluminum levels are elevated in the preparation, the colloid can be less stable and may not distribute as intended through the reticuloendothelial system (RES). Instead, there may be an aberrant concentration in the lungs, which can create challenges in accurately interpreting lung function and pathology on imaging.

The other organs mentioned, such as the liver, kidneys, and heart, typically do not reflect the excess uptake associated with aluminum contamination in the same way as the lungs do. While these organs may have their normal uptake patterns during a scintigraphy study, the unique interaction of sulfur colloid with aluminum favors deposition in the pulmonary tissue, emphasizing the importance of ensuring low aluminum levels in radiopharmaceutical preparations to prevent diagnostic interference.