Simultaneous determination of 11 phthalates and di(2-ethylhexyl) adipate in foods by GC/MS (SIM)

Eleven phthalate esters (PhE's) and di(2-ethyhexyl) adipate (DEHA) in foods were simultaneously determined. PhE's in 50 g of food sample were extracted with acetone followed by evaporation, and sodium chloride solution was added to the residue before extraction with ethyl acetate and n-hexane mixture (1:2). The extract was evaporated and partitioned between acetonitrile and n-hexane. The acetonitrile layer was evaporated and cleaned up on a Florisil column. PhE's were determined by GC/MS (SIM). Contamination sources were carefully eliminated and the background levels were 4.3 similar to 12.1 ng/g for di(2-ethylhexyl) phthalate (DEHP) or ND similar to 9.2 ng/g for di-n-butyl phthalate. Recoveries of PhE's from packaged lunch, potato, polished rice and butter were 55.9 to 107.3% at fortification levels of 1 to 1,250 ng/g. Twenty-three samples of commercial foods were examined, and DEHP was detected in packaged lunch (54 similar to 272 ng/g) or in butter (324 similar to 1,008 ng/g). Some of the other PhE's or DEHA were also detected.