Regional Variation in Human Exposure to Persistent Organic Pollutants in the United States, NHANES

Table 3

Geometric mean and selected percentiles of serum DDE concentrations (in ng/g of lipid or parts per billion on a lipid weight basis) for the US population by geographic area, NHANES 1999–2004.

	Ages of 20 years and older
DDE	Geometric mean	Percentile (95% CI)
1999–2004	(95% CI)	50th	90th
Northeast	247 (211–284)	198 (174–233)	1180 (972–1400)
Midwest	232 (201–263)	195 (175–240)	919 (706–1150)
South	311 (262–360)	260 (227–310)	1480 (1180–1870)
West	476 (390–563)	421 (360–545)	1720 (1440–2090)

Regional means with the same letter superscript are not significantly different from each other based on analysis of covariance adjusting for age, smoking status, gender, and race/ethnicity.