20623
Bisphenol A analogs are a class of chemicals known as diphenylmethanes , which contain two benzene rings separated by one central carbon atom , usually with a para - hydroxy group on both benzene rings .
 Bisphenol A, diphenylmethanes, benzene, para - hydroxy, benzene
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Bisphenol A, diphenylmethanes, benzene, para - hydroxy, benzene