21235
For this purpose , cells were co - exposed to MeHg and TCDD and the expression of CYP1A1 mRNA , protein , and catalytic activity levels were determined .
 Chemical: MeHg; Chemical: TCDD
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: MeHg; Chemical: TCDD