Radiation Dose Estimates for N-13 Ammonia

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	Estimated Radiation Dose (mGy/MBq)
ORGAN	mGy/MBq	rad/mCi
Adrenals	1.7E-03	6.2E-03
Brain	4.7E-03	1.7E-02
Breasts	1.3E-03	4.7E-03
Gallbladder Wall	1.9E-03	6.9E-03
LLI Wall	1.7E-03	6.2E-03
Small Intestine	1.7E-03	6.2E-03
Stomach	1.6E-03	5.9E-03
ULI Wall	1.7E-03	6.2E-03
Heart Wall	1.6E-03	5.9E-03
Kidneys	1.6E-03	5.9E-03
Liver	3.8E-03	1.4E-02
Lungs	1.5E-03	5.4E-03
Muscle	1.4E-03	5.3E-03
Ovaries	1.7E-03	6.4E-03
Pancreas	1.7E-03	6.4E-03
Red Marrow	1.8E-03	6.6E-03
Bone Surfaces	1.5E-03	5.6E-03
Skin	1.2E-03	4.6E-03
Spleen	1.5E-03	5.7E-03
Testes	1.4E-03	5.4E-03
Thymus	1.5E-03	5.4E-03
Thyroid	1.5E-03	5.5E-03
Urinary Bladder Wall	6.9E-03	2.6E-02
Uterus	1.8E-03	6.8E-03
Effective Dose Equivalent	2.2E-03 mSv/MBq	8.3E-03 rem/mCi

Based on distribution data gathered in human subjects by Lockwood et al. (J Clin Invest 63:449-460, 1979). Assumed distribution and retention:

Brain 6.9% Tb = ñ
Liver 7.1% Tb = ñ
Total Body 94% Tb = ñ
6% Tb = 10 min

6% of material cleared through urinary bladder, Tb = 10 min. Bladder voiding
interval 4.8 hours.

Dynamic bladder model with 4.8-hour voiding interval. Estimate calculated using phantom of Cristy & Eckerman (Report ORNL/TM-8381/V1 & V7)