20268
Aflatoxin M1 ( AF M1 ) , a hydroxylated metabolite of AF B1 , is an important toxin that can contaminate the milk of lactating mothers .
 Chemical: Aflatoxin M1; Chemical: AF M1; Chemical: AF B1
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: Aflatoxin M1, AF M1, AF B1 
Answer:
 Chemical: Aflatoxin M1; Chemical: AF M1; Chemical: AF B1