Table 1. Description of variables and parameters used to estimate distribution of indirect and direct doses.

Description	Symbol	Parameter	Source
Pathogen concentration	C
Soil/gram	a CSp	See S1 Table	This study
Surface water/mL	CWp	See S1 Table	This study
Transfer efficiency from object	TE
Soil adherence	TES	Lognormal (0.52,0.9) mg/cm2	Finley et al. (1994) [39]
Water film thickness	TEW	Uniform (0.00234, 0.00499) cm	EPA Exposure (1987) [38]
Surface area of hand	SAHi
6 to <12 months	SAH1	Normal (240, 18.2) cm2	EPA Exposure (2011) [32]
12 to <24 months	SAH2	Normal (300, 30.4) cm2	EPA Exposure (2011) [32]
24 to <72 months b	SAH3	Normal (347.5, 48.6) cm2	EPA Exposure (2011) [32]
Fraction of hand	FH
Contacting object	FHO	Normal (0.215, 0.111) %	Auyueng et al. (2008) [40]
Contacting mouth	FHM	Normal (0.18, 0.076) %	Auyueng et al. (2008) [40]
Transfer efficiency from hand	TEH
Hand-to-mouth	TEHM	0.33 (%)	Rusin et al. (2002) [41]
Volume ingested during direct ingestion	V
Geophagia	VS	1.25 grams	Ngure et al. 2013 [27]
Drinking surface water	VW	5 mL	Labite et al. 2010 [15]

^a Converted C_Sp to mg

^b Averaged from reported data for age groups 2 to 3 years and 3 to 6 years.