Figure 4

Extrapulmonary distribution of⁶⁵Zn post-IT instillation of⁶⁵ZnO and SiO ₂ -coated⁶⁵ZnO NPs. Data are % of instilled dose recovered in all secondary tissues examined. It included blood, thoracic lymph nodes, bone, bone marrow, skin, brain, skeletal muscle, testes, kidneys, heart, liver, and the gastrointestinal tract. There was a rapid absorption and accumulation of ⁶⁵Zn in secondary tissues. At day 2, 59-72% of the dose was detected in extrapulmonary organs. Then, ⁶⁵Zn levels decreased over time to 25-37% by day 28. Significantly more ⁶⁵Zn was detected in secondary organs at all time points in rats instilled with uncoated ⁶⁵ZnO NPs.