Table 5: HKAFs obtained by the “distinct subpopulation” approach on the basis of 100,000 Monte Carlo iterations in adults, neonates, infants, and pregnant women and by the “whole population” approach for the Canadian population.

HKAF assumption

Dose metrics

Benzene

1,4-Dioxane

CAss

RAM

CAss

RAM

“Whole population” approach

Based on 95th percentile

1.2

1.3

2.1

1.4

Based on 99th percentile

1.3

1.4

2.8

1.6

Based on 95th percentile

1.2

1.2

2.1

1.4

Based on 99th percentile

1.3

1.4

2.8

1.6

“Distinct subpopulation” approach

In adults

Based on 95th percentile

1.2

1.2

2.1

1.4

Based on 99th percentile

1.3

1.3

2.8

1.6

Based on 95th percentile

1.2

1.2

2.0

1.4

Based on 99th percentile

1.3

1.3

2.7

1.6

In neonates

Based on 95th percentile

1.6

1.1

6.6

1.2

Based on 99th percentile

1.7

1.2

8.5

1.4

Based on 95th percentile

1.6

1.1

6.5

1.2

Based on 99th percentile

1.7

1.2

8.3

1.4

In infants

Based on 95th percentile

1.3

1.2

3.1

1.4

Based on 99th percentile

1.4

1.3

3.8

1.6

Based on 95th percentile

1.3

1.2

3.0

1.4

Based on 99th percentile

1.4

1.3

3.8

1.5

In pregnant women

Based on 95th percentile

1.4

1.5

2.7

1.8

Based on 99th percentile

1.5

1.6

3.5

2.1

Based on 95th percentile

1.4

1.5

2.6

1.8

Based on 99th percentile

1.5

1.6

3.5

2.1

Italicized values indicate the highest HKAF among each subpopulation for a given dose metric. Computed as the ratio of the upper percentile value in the Canadian population (95th or 99th) to the median in 100,000 adults. Computed as the ratio of the upper percentile value in the Canadian population (95th or 99th) to its median. Computed as the ratio of the upper percentile value in the subpopulation (95th or 99th) to the median in adults. Computed as the ratio of the upper percentile value in the subpopulation (95th or 99th) to the median in the Canadian population. CAss: blood concentration of parent compound; HKAF_{(ad/pop)}: human kinetic adjustment factor using either the median in adult (“ad”) or whole population (“pop”) as referent; RAM: rate of metabolism.