17950
Epidemiologic studies showed that the occurrence of melamine - related urolithiasis is related to both the concentration of melamine in ingested milk products and the duration of ingestion .
 Chemical: melamine; Chemical: melamine
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: melamine; Chemical: melamine