Table 1.

Median and 95th percentile estimates of DAP metabolites of OP insecticides in the NHANES III (1988–1994) and 1999–2004.

Analyte/ survey yearsa		LOD (µg/L)	Volume based (µg/L)			Creatinine adjusted (µg/g creatinine)			FOD (%)
			n	Median	95th percentile	Median	95th percentile
DMP
	1988–1994		0.5		192		2.07*		13.4**		2.14*		25.2*		90.4
	1999–2000		0.58		814		0.68		9.7		0.76		14.6		50.9
	2001–2002		0.5		1,121		< LOD		11.5		< LOD		11.5		45.7
	2003–2004		0.5		938		< LOD		14.1		< LOD		13.5		46.1
DMTP
	1988–1994		0.18		189		4.83*		65.4*		4.49*		42.6		86.8
	1999–2000		0.18		813		2.30		39.0		1.90		47.5		61.3
	2001–2002		0.4		1,121		< LOD		30.0		< LOD		25.2		46.9
	2003–2004		0.5		715		1.78		28.5		1.67		30.4		73.5
DMDTP
	1988–1994		0.08		194		0.57*		17.4		0.47*		19.0		65.5
	1999–2000		0.08		814		< LOD		17.0		< LOD		20.5		47.3
	2001–2002		0.1		1,122		< LOD		4.90		< LOD		6.33		30.8
	2003–2004		0.1		925		< LOD		5.07		< LOD		5.71		35.8
DEP
	1988–1994		0.2		184		4.6*		26.9*		5.00*		61.5*		92.4
	1999–2000		0.2		814		1.10		11.0		0.86		12.1		67.6
	2001–2002		0.2		1,122		< LOD		10.4		< LOD		7.34		48.1
	2003–2004		0.1		921		< LOD		14.2		< LOD		11.9		46.2
DETP
	1988–1994		0.09		196		1.16*		17.9*		1.40*		13.8*		84.7
	1999–2000		0.09		814		0.49		2.0		0.25		2.75		52.3
	2001–2002		0.1		1,122		0.54		3.83		0.49		4.69		67.8
	2003–2004		0.2		918		< LOD		2.65		< LOD		2.82		47.2
DEDTP
	1988–1994		0.05		197		< LOD		2.42*		0.12		2.15*		43.2
	1999–2000		0.05		814		0.09		0.90		0.08		0.86		54.4
	2001–2002		0.1		1,118		< LOD		0.83		< LOD		1.03		18.8
	2003–2004		0.1		938		< LOD		0.22		< LOD		0.4		7.51
aSurvey years 1988–1994 were a part of the NHANES III survey call-back cohort, and the calculated percentile estimates are not representative of the U.S. population. *Represents a statistically significant (p < 0.05) decrease observed from NHANES III and all subsequent NHANES cycles. **Represents a significant (p < 0.05) decrease from NHANES III to NHANES 1999–2000 only.