23692
Blood lead , serum creatinine , and serum urea nitrogen can be useful biomarkers of lead exposure among populations under environmental stress .
 Chemical: creatinine; Chemical: urea; Chemical: nitrogen
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: creatinine; Chemical: urea; Chemical: nitrogen