Chronic exposure assessmentΒΆ
In a chronic exposure assessment, the main interest goes to the fraction of individuals with a usual intake per day higher than an intake limit or point of departure (PoD). The PoD is calculated as the acceptable daily intake (ADI) * safety factor (SF). Usual intake is defined as the long-run average of daily exposure to a substance or group of substances by an individual. Usually, for an individual, dietary recall data are available on 2 (or more) consecutive days. We assume an equal number of days for each individual, unless specified differently in table for Individuals.
For a chronic exposure assessment the available data are used to calculate exposures per person-day (daily intake):
where \(y_{ij}\), \(x_{ijk}\) and \(bw_{i}\) are defined as before but now concentrations of the substance found in food \(k\) enter the model as the estimated mean substance concentration value \(c_{k}\). Using the person-day intakes MCRA, provides a number of intake models to calculate the distribution of usual intake at the person level.