8894
Overall , 16 phthalates and DEHA were measured by gas chromatography - mass spectrometry in a total of 171 duplicate diet samples collected over 7 consecutive days , and 20 phthalate metabolites were analyzed in the urine samples collected over 7 consecutive days using a liquid chromatography - tandem mass spectrometry method .
 phthalates, DEHA, phthalate
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 phthalates, DEHA, phthalate