csefh - Kinder-Umwelt-Gesundheit

everages grouped by age and gender for the U.S.
population, based on this calculation.
11.5 CONVERSION BETWEEN WET AND
DRY WEIGHT INTAKE RATES
The intake rates presented in this chapter are
reported in units of wet weight (i.e., as-consumed or
uncooked weight of meats and dairy products consumed
per day or per eating occasion). However, data on the
concentration of contaminants in meats and dairy
products may be reported in units of either wet or dry
weight.(e.g., mg contaminant per gram-dry-weight of
meats and dairy products.) It is essential that exposure
assessors be aware of this difference so that they may
ensure consistency between the units used for intake
rates and those used for concentration data (i.e., if the
contaminant concentration is measured in dry weight of
Child-Specific Exposure Factors Handbook
Chapter 11 - Intake of Meats, Dairy Products and Fats
11.6 CONVERSION BETWEEN WET WEIGHT
AND LIPID WEIGHT INTAKE RATES
In some cases, the residue levels of
contaminants in meat and dairy products may be
reported as the concentration of contaminant per gram
of fat. This may be particularly true for lipophilic
compounds. When using these residue levels, the
assessor should ensure consistency in the exposure
assessment calculations by using consumption rates that
are based on the amount of lipids consumed for the
meat or dairy product of interest.
If necessary, wet weight (e.g., as-consumed)
intake rates may be converted to lipid weight intake
rates using the fat content percentages presented in
Table 11-28 and the following equation:
meats and dairy products, then the dry weight units
⎡ L ⎤
IR
lw
= IR
ww ⎢⎣100 ⎥ should be used for their intake values).
If necessary, wet weight (e.g., as consumed)
⎦
(Eqn. 11-3)
intake rates may be converted to dry weight intake rates where:
using the moisture content percentages presented in
Table 11-28 and the following equation:
IRlw =
Irww =
L =
lipid weight intake rate;
wet weight intake rate; and
percent lipid (fat) content.
IR
dw
=
⎡100 − W ⎤
IR
ww ⎢
⎣ 100 ⎥
⎦
(Eqn. 11-1)
Alternately, wet weight residue levels in meat and dairy
products may be estimated by multiplying the levels
based on fat by the fraction of fat per product as
where: follows:
IRdw =
IRww =
W =
dry weight intake rate;
wet weight intake rate; and
percent water content
C
ww
=
⎡ L ⎤
C
lw ⎢
⎣100
⎥
⎦
(Eqn. 11-4)
Alternatively, dry weight residue levels in meat and where:
diary products may be converted to wet weight residue
levels for use with wet weight (e.g., as-consumed)
intake rates as follows:
C ww =
Clw =
L =
wet weight intake rate;
lipid weight intake rate; and
percent lipid (fat) content.
C
ww
=
⎡100 − W ⎤
C
dw ⎢
⎣ 100 ⎥
⎦
(Eqn. 11-2) The resulting residue levels may then be used in
conjunction with wet weight (e.g., as-consumed)
consumption rates. The total fat content data presented
in Table 11-28 are for selected meat and dairy products
where: taken from USDA, 2007.
Cww = wet weight intake rate;
Cdw = dry weight intake rate; and
W = percent water content.
The moisture content data presented in Table 11-28 are
for selected meats and dairy products taken from USDA
(2007).
Page Child-Specific Exposure Factors Handbook
11-12 September 2008