	Infants	Children	Teens	Adults	Reference
Surface area: body mass ratio (m²/kg)*	Newborn 0.067	Young child 0.047	Older child 0.033	Adult 0.025	Silvaggio and Mattison (1993)
Respiratory ventilation rates	Infant	-	-	Adult	Silvaggio and Mattison (1993)
Respiratory volume (mL/kg/breath)^†	10	-	-	2	Silvaggio and Mattison (1993)
Alveolar surface area (m²)^‡	3	-	-	10
Respiration rate (breaths/min)^§	40	-	-	75
Respiratory minute ventilation rate^¶	133		-	2
Drinking water (tap)	<1 year	1-10 years	11-19 years	20-64 years	Snodgrass (1992)
Mean intake (mL/kg/day)^**	43.5	35.5	18.2	19.9	Snodgrass (1992)
Fruit consumption (g/kg/day)^††	<1 year	3-5 years	12-19 years	40-69 years	U.S. Environmental Protection Agency (1997a)
Citrus fruits	1.9	2.6	1.1	0.9
Other fruits (including apples)	12.9	5.8	1.1	1.3
Apples	5.0	3.0	0.4	0.4
Soil ingestion (mg/day)^‡‡	-	5,000^§§	-	Adult	U.S. Environmental Protection Agency (1997b)
Pica child	-	2.5 years	-	-
Outdoor	-	50	-	20^¶¶
Indoor	-	60	-	0.4
Differences in gastrointestinal absorption of lead	0-2 years	2-6 years	-	Adult	U.S. Environmental Protection Agency (1997c)
	42%-53%	30%-40%	-	7%-15%
		6-7 years 18%-24%
Adapted from Selevan et al. (2000). ^Square meters per kilogram. ^†Milliliters per kilogram per breath. ^‡Per square meter. ^§Breaths per minute. ^¶Milliliters per kilogram body weight per square meter lung surface area per minute. ^*Milliliters per kilogram per day. ^††Grams per kilogram per day. ^‡‡Milligrams per day. ^§§ATSDR (2001a). ^¶¶Gardening for adults.

Revised 2002-07-30.

Agency for Toxic Substances and Disease RegistryCase Studies in Environmental Medicine (CSEM) Pediatric Environmental Health Differences in Children and Adults

Table 3. Differences in Children and Adults