30120
The treated groups were exposed to vapours of a mixture of benzene , toluene and xylene at doses of 450 and 675 ppm , for 6 h day ( - 1 ) for a short - term of 7 - day exposure period .
 Chemical: benzene; Chemical: toluene; Chemical: xylene
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: benzene, toluene, xylene 
Answer:
 Chemical: benzene; Chemical: toluene; Chemical: xylene