Radiation Dose Estimates for Tc-99m ECD*

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	Estimated Radiation Dose
ORGAN	mGy/MBq	rad/mCi
Adrenals	2.5E-03	9.3E-03
Brain	5.5E-03	2.0E-02
Breasts	9.4E-04	3.5E-03
Gallbladder Wall	2.7E-02	1.0E-01
LLI Wall	1.5E-02	5.4E-02
Small Intestine	1.0E-02	3.7E-02
Stomach	2.5E-03	9.3E-03
ULI Wall	1.7E-02	6.2E-02
Heart Wall	1.8E-03	6.5E-03
Kidneys	7.7E-03	2.9E-02
Liver	5.4E-03	2.0E-02
Lungs	2.0E-03	7.4E-03
Muscle	2.4E-03	8.8E-03
Ovaries	7.8E-03	2.9E-02
Pancreas	2.9E-03	1.1E-02
Red Marrow	2.4E-03	9.0E-03
Bone Surfaces	3.7E-03	1.4E-02
Skin	1.2E-03	4.3E-03
Spleen	2.0E-03	7.3E-03
Testes	3.5E-03	1.3E-02
Thymus	1.2E-03	4.6E-03
Thyroid	1.3E-03	4.8E-03
Urinary Bladder Wall	7.3E-02	2.7E-01
Uterus	1.1E-02	4.1E-02
	2.7E-03	1.0E-02
Effective Dose Equivalent	1.1E-02 mSv/MBq	4.2E-02 rem/mCi

*Based on data gathered in 16 patients. Assumed distribution and retention:
Brain 4.6% Tb = 22.4 hr 2.1% Tb = 0.554 hr
Heart Wall 0.43% Tb = 1.9 hr 0.32% Tb = 0.31 hr
Kidneys 1.2% Tb = 14.4 hr 7.8% Tb = 0.4 hr
Liver 3.5% Tb = 18.6 hr 15.5% Tb = 0.42 hr
Lungs 0.97% Tb = 12.0 hr 4.7% Tb = 0.25 hr
Gallbladder: average residence time 0.185 hr
Total Body 30.6% Tb = 31.2 hr 69.4% Tb = 0.854 hr
Urinary Bladder 19% Tb = 68.5 hr 70% Tb = 1.11 hr
GI Tract: 11% of total activity cleared into small intestine, follows
GI tract kinetics as in ICRP 30.