7149
We report that 2 , 3 , 7 , 8 - tetrachlorodibenzo - p - dioxin ( TCDD ) significantly impairs this regeneration .
 Chemical: 2 , 3 , 7 , 8 - tetrachlorodibenzo - p - dioxin; Chemical: TCDD
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: 2 , 3 , 7 , 8 - tetrachlorodibenzo - p - dioxin, TCDD 
Answer:
 Chemical: 2 , 3 , 7 , 8 - tetrachlorodibenzo - p - dioxin; Chemical: TCDD