1135
Urinary excretion of free and total ( free plus conjugated ) forms of methyl , ethyl , n - propyl and n - butyl parabens ( MP , EP , PP and BP , respectively ) and their metabolite p - hydroxybenzoic acid were measured for 111 pregnant Japanese women .
 methyl , ethyl , n - propyl and n - butyl parabens, p - hydroxybenzoic acid
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 methyl , ethyl , n - propyl and n - butyl parabens, p - hydroxybenzoic acid