Table 8.

Comparison of soil lead concentrations from sampled childcare centers around the world and U.S. soil lead background concentrations.

Reference	Geographic Location	Soil Pb Concentration (mg/kg)
This Study	Pacific Northwest, USA	22 (12); 8.4–50a
Marshall et al. [23]	Clark County, Nevada	35.89 (40.77); <7–160a
HUD Report 2003 [5]	USA	81 (329); 28; 3582b
Button [22]	greater Cincinnati area (5 county region surrounding the University of Cincinnati campus), Ohio	11–990c,d; 17–4636c,e
Weismann et al. [20]	Iowa City, Iowa	<10–1100c
Washington State DOH [29]	Six Counties, Washington	0–1400c
Aclan et al. [28]	Manila, Philippines	1.12–2.59c
Fernandez et al. [26]	Caracas Valley, Venezuela	142–465c
Orlova et al. [24]	Moscow, Russia	500–2000c
Haugland et al. [14]	Bergen, Norway	91; 39; <5–1779f
John et al. [25]	Soshanguve, Pretoria East, South Africa	17.7g; 6.9h
Berglund et al. [27]	Sweden	410; 480; 610i
https://www.epa.gov/superfund/usgs-background-soil-lead-survey-state-data	Washington	26.6; 6.1–513.0j
	Oregon	14.4; 2.7–44.7j
	Idaho	21.2; 5.5–158j

^aMean (standard deviation); range.

^bMean (standard deviation); median; maximum.

^cRange.

^dPlayground soil.

^eBuilding perimeter soil.

^fMean; median; range.

^gAverage. Soshanguve.

^hAverage. Pretoria East.

ⁱIndividual concentrations reported.

^jMean; range.