20569
Lactating Sprague - Dawley rats ( SD rats ) were randomly divided to four groups : 0ppm lead acetate ( Pb ) ; 0ppm Pb and 0 . 2ppm sodium selenite ( Se ) ; 100ppm Pb ; 100ppm Pb and 0 . 2ppm Se .
 Chemical: lead acetate; Chemical: Pb; Chemical: Pb; Chemical: sodium selenite; Chemical: Se; Chemical: Pb; Chemical: Pb; Chemical: Se
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: lead acetate; Chemical: Pb; Chemical: Pb; Chemical: sodium selenite; Chemical: Se; Chemical: Pb; Chemical: Pb; Chemical: Se