641
The synthetic estrogen 17 - alpha - ethynylestradiol ( EE2 ) , a component of birth control and hormone replacement therapy , is discharged into the environment via wastewater treatment plant ( WWTP ) effluents .
 Chemical: estrogen; Chemical: 17 - alpha - ethynylestradiol; Chemical: EE2
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: estrogen; Chemical: 17 - alpha - ethynylestradiol; Chemical: EE2