Children intake estimates

For a 4-6-year-old child however, the mean and 95th percentile of Pb intakes estimated on the basis of age-specific consumption data from the 2000-2002 dietary survey (Table 9.5) correspond to 13 and 20 percent of the PTWI value, respectively. 

The child s estimated blood volume is 80 mL/kg, which is larger than an adult s on a milliliter per kilogram basis. Therefore, small amounts of blood loss can impair perfusion and decrease circulating blood volume. Children have greater cardiac reserves and catecholamine responses compared with adults, allowing them to compensate for fluid losses from hemorrhage, diarrhea, or lack of oral intake. However, shock and cardiopul-... 

Based on the food intake estimated with the market basket survey in Japan, the 95-percentile of the intake of a one-year old female of 0.68 pg kg per day is applied to the endpoint of tubular pigmentation, and the 95-percentile of the intake of a 25-year old female of child-bearing age of 0.223 pg kg per day is applied to the endpoint of developmental toxicity. The result of risk characterization is shown in Table 28. 

PCF exposure risk assessment for infants and evaluation of lactation as an exposure pathway has also been assessed [91]. For a 5-kg Swedish child consuming breast milk at a rate of 800 ml/day, PFOS intake can be estimated at 48-380 (mean, 160) ng/day, or approximately 9.6-75 (mean, 32) ng/kg b.w. per day. The calculated total amount of PFC transferred by lactation to a breasted infant in this study was, approximately, 200 ng/day. As aU the Swedish human mUk samples came from the area of Uppsala, this intake estimate may not be representative of breastfed infant exposure to PFOS throughout Sweden. Likewise, the Swedish milk-based intake values may not in principle be extendable to the other European breastfed infants despite the concentrations detected in the Swedish human milk seem to be corroborated by the findings reported for other countries (Fig. 2). 

RECOMMENDED DAILY ALLOWANCES OF SODIUM. The salt requirements of the infant and young child are estimated to be about 120-300 mg per day. Human milk contains 161 mg of sodium per liter, whereas commonly used bottle formuleis contains between 161 and 391 mg per liter, and cow s milk contains about 483 mg per liter. Average intake of sodium during the first year of life ranges from about 300 mg per day at 2 months of age to about 1,400 mg per day at 12 months ar in excess of needs. 

FDA estimated that in 1990, toddlers (2-year-olds) received 16% of their total lead exposure from food (5 tg/day), 1% from soil, 7% from water, and 75% from dust. EPA estimated that in 1990 lead intake from U S. drinking water would be 11.9 pg/day for a 6-year-old child and 7.5 pg/day for an infant less than 1 year old (Cohen 1988b). A study of lead in the diet of Canadian infants found an average intake by children 0-1 years of age to be 16.5 pg/day when both food and water ingestion were considered (Dabeka and McKenzie 1988). 

In 1982-1983, the baseline value for daily intake of lead by inhalation in a nonurban environment was estimated to be 0.5 pg/day for a 2-year-old child. The baseline value was based on an average atmospheric lead concentration of 0.1 pg/m3 and an indoor/outdoor lead concentration ratio of 0.5. In an urban environment, the indoor/outdoor ratio was assumed to be approximately 0.8 (EPA 1986a). Drastic reductions in the lead content of gasoline since 1986 have resulted in a 64% decrease in lead emissions to the atmosphere (see Section 5.4.1). 

According to US-EPA (1997), data on soil ingestion rates for children who deliberately ingest soil (pica) are limited however, it does not appear to be a very common behavior. This conclusion is based on the seven key smdies used by US-EPA to estimate the daily soil intake in children, where only a single child, out of more than 600 examined, exhibited pica behavior directed toward sod. The results for this child are shown in Table 7.5. 

Short period of sampling therefore the value is not an estimate for usual daily intake. ° Used for very short-term (acute) exposure. The value is based on a single pica child. 

In 1992, the US Public Health Service issued a recommendation that all women capable of becoming pregnant consume 400 tg of folic acid daily to reduce the risk of having a child born with a neural tube defect (Centers for Disease Control and Prevention 1992). Food fortification was implemented to reduce the number of pregnancies affected by NTDs (Centers for Disease Control and Prevention 2005). Estimates have shown that the additional intake of folic acid through food fortification has been effective in reducing the prevalence of NTDs at birth. 

Barltrop D (1966) The prevalence of pica. Am J Dis Child 112 116-123 Barltxop D, Strehlow CD, Thorton I, Webb JS (1974) Significance of high soil lead concentrations for childhood lead burden. Environ Health Perspect 7 75-82 Beloian A (1982) Use of a food consumption model to estimate human contaminant intake. Environ Monitor Assess (in press)... 

Various primary sources for estimating the exposure parameters associated with daily intake quantities of (lead-containing) media were used and are noted. A child exposure-specific source of parameter selection for media of interest was the U.S. EPA Child-Specific Exposure Factors Handbook (2008). 

TABLE 7.16 Estimated Mean Daily Tap Water Pb Intakes for Children in Time Periods and Child Ages the Indicated U.S. Communities for the Indicated ... 

The prospective studies which are in progress are obtaining serial estimations of blood lead, and in many cases are collecting, or plan to collect, teeth as well. This will provide more information on the relationship of the different measures, and the pattern over time and different developmental stages. At the same time, since several of the prospective studies are investigating the potential sources of lead, such as dirt and dust, to which the child is exposed, it is expected that this will produce a great deal of information relating sources and habits associated with intake, to body burden. 

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