2.16 SPECIAL FOOD INTAKE
When measurements of contaminated food concentrations
are available, the dose and health impacts to individuals consuming the
foods may be estimated. This pathway involves direct ingestion of foods
at the concentration specified. Considerations given to this exposure pathway
are as follows.
- Transport Medium:
- measured food concentration at the time of ingestion by the exposed individual, Cmsi, mg/kg or pCi/kg
- Special Process:
- none (food is ingested directly)
- Exposure Factors:
- food ingestion rate and exposure duration.
There are no special processes applied to modify the given food concentration.
For chemical pollutants, the average daily dose from
ingestion of a special food is calculated, as follows:
(89)
where
Dfdi = average daily dose from chemical pollutant i from ingestion of special foods (mg/kg/d)
Cmfi = concentration of chemical pollutant i in special food (mg/kg)
Ufd = ingestion rate of special food (kg/d)
Ffd = fraction of days per year that special food ingestion occurs (dimensionless)
EDfd = exposure duration for the special food ingestion pathway (yr)
ATfdi = averaging time for pollutant i for the special food ingestion pathway (yr)
BWfd = body weight of exposed individual for the special food ingestion pathway (kg).
The averaging time for noncarcinogenic chemicals is set to the exposure
duration, and the averaging time for carcinogenic chemicals is fixed at
70 years.
For radionuclides, the total lifetime dose from ingestion
of special foods is estimated as follows:
(90)
where
Dfdi = total lifetime dose from radionuclide i from ingestion of special foods (rem)
Cmfi = concentration of radionuclide i in special food (pCi/kg)
DFgi = dose conversion factor for ingestion of radionuclide i (rem/pCi ingested)
and other terms are as previously defined.