33173
The biological half-life of Am is 50 years in the bones and 20 years in the liver , whereas in the gonads ( testicles and ovaries ) it remains permanently ; in all these organs , americium promotes formation of cancer cells as a result of its radioactivity .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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