Determination of organic phosphate triesters in human adipose tissue

A method of analysis has been developed for the determination of organic phosphate triesters in human adipose fat at low ng/g levels. After fat extraction from the tissue with benzene (or acetone-hexane, 15 + 85, v/v), phosphates were fractionated from fat by gel permeation chromatography with methylene chloride-cyclohexane (5 + 95, v/v) as solvent. After Florisil column cleanup, the GPC extract was analyzed by capillary column gas chromatography using a nitrogen-phosphorus selective detector. Recoveries at the 2.5, 10, and 25 ng/g levels were greater than 75% except for tri(2,4-xylenyl) phosphate (ca 65%). Of 16 human adipose tissue samples analyzed, 5 contained tris(1,3-dichloropropyl) phosphate in the range of 0.5 to 110 ng/g, 4 contained tributoxyethyl phosphate in the range of 4.0 to 26.8 ng/g, and one contained tributyl phosphate at 9.0 ng/g.