SUPPLEMENTAL READINGS:

How are children different from adults? (Bearer-EHP1995)

And related US EPA publications:

Vulernability and health problems in children

Critical periods in development

Children's environmental exposures

Figure 1. Pesticide air concentrations in child and adult breathing zones in a ventilated room. The concentrations of a pesticide are much higher in the breathing zone of a child than of an adult, even 24 hours after the pesticide is applied. Thus, children may have a greater exposure to pesticides applied around the house than adults do. [Back to movie]

Figure 2. Average food consumption by age. [Back to movie]

 Table 1. Stages of prenatal and postnatal organ structural development.
[Back to movie]

Organ System	Early Prenatal	Mid-Late Prenatal	Postnatal
CNS	3-16 weeks	17-40 weeks	Continues into adulthood
Ear	4-16 weeks	17-20 weeks	---
Heart	3-8 weeks	---	---
Immune system	8-16 weeks	17-40 weeks	Immunocompentence: 0-1+ years Immune memory: 1-18 years
Kidneys	4-16 weeks	17-40 weeks	Nephrons mature in outer cortical region, providing ability to concentrate urine
Limbs	4-8 weeks	---	---
Lungs	3-16 weeks	17-40 weeks	> 80% of alveoli are formed after birth to age 8-10
Palate	6-10 weeks	---	---
Reproductive system	7-9 weeks	10-40 weeks	Sexual maturation; breast and cervix development: 9-16 years
Skeleton	1-2 weeks	---	Ossification continues for ~25 years
Teeth	12-16 weeks	17-24+ weeks	Primary dentition: 4 months after conception to 3 years postnatal. Permanent dentition: 3 months after birth to 25 years.

Figure 3. Half-life results for caffeine and theophylline. Note, half-life of theophylline increases again in adolescence, possibly due to competition with steroid hormones. [Back to movie]