Table 1 OP metabolites analyzed and possible precursor compounds

Chlorethoxyphos, chlorpyrifos, coumaphos, diazinon, disulfoton, ethion, parathion, phorate, phosalone, sulfotep, terbufos

Diethyl phosphate

DEP^a

10

Diethyl thiophosphate

DETP^a

3.2

Azinphos-methyl, dichlorvos, dicrotophos, dimethoate, fenitrothion, fenthion, malathion, methyl parathion, trichlorfon, chlorpyrifos-methyl, methidathion, mevinphos, oxydemeton-methyl, phosmet, primiphos-methyl, temephos, tetrachlorvinphos, isazofos-methyl, naled

Dimethyl thiophosphate

DMTP^a

1.6

Dimethyl dithiophosphate

DMDTP^a

1.6

Chlorpyrifos, chlorpyrifos-methyl

3,5,6-trichloro-2-pyridinol

TCPY^b

0.8

Parathion, methyl parathion

p-nitrophenol

PNP^b

0.8

Pirimiphos-methyl

2-diethylamino-6-methyl-4-pyrimidinol

DEAMPY^b

1.6

Diazinon

2-isopropyl-4-methyl-6-hydroxypyrimidine

IMPY^b

1.6