determination of diphenyl and ophenylphenol in agricultural products by gcms a simple determination method of diphenyl dp and ophenylphenol opp in agricultural products by gcms was examined dp and opp were extracted with ethyl acetate in the presence of anh sodium sulfate after addition of nbutanol the extract solution was concentrated cleanup was achieved by shaking with graphitized bulk carbon supelclean envicarb addition of polyethylene glycol sharpened the opp peak on gcms analysis the recoveries from 9 kinds of agricultural products spiked at 001 and 05 microgg each were mostly in the range of 70 to 120 except for 50 recovery of opp from barley spiked at 001 microgg the quantification limits sn or 10 of dp and opp were 00013 and 0005 microgg 00025 and 001 microgg in barley and soybean respectively