4710
Age , duration of breastfeeding , annual consumption frequency of seal meat , and monthly consumption frequency of tomato products were significant predictors of blood mercury levels , whereas annual consumption frequencies of beluga muktuk , walrus , Arctic char , and caribou meat were not .
 mercury
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 mercury