Table 3.
Plausibility check of the fraction dermally absorbed (Fabs), as obtained by three different approaches, in terms of serum clearance of unconjugated BPA.
Approach | Fabs (%) | Dose D (nmol) | AUC (nM × h) | CL (L/h) |
---|---|---|---|---|
Recovery of total BPA in urine | 1 | 34,141 | 7.51 | 45 |
Serum AUCs of total BPA after oral and dermal administration | 2.2 | 95.5 | ||
Mass-balance considerations based on recovery of unabsorbed BPA | 12–29 | 545–1318 |
The absolute dermal dose (D, nmol) derives from the per-body-weight dose of 100 μg/kg BW multiplied by a body weight of 80 kg and divided by the molecular mass of 234.32 g/mol for d6-BPA. The assumed body weight is representative for the six subjects from which the estimate for the mean serum AUC of 7.51 nM × h for unconjugated BPA was obtained. The serum clearance for unconjugated BPA (CL) was calculated as: CL = Fabs/100% × D/AUC.