Table 4.
Model parameters from the fit of the Michaelis–Menten model to the NTP data. Model parameters c and k are from the first model; parameters β are from the reparameterized model; V and the Ts are in both models.
| Parameter | Values for FT4 (95% confidence limits) | Values for TT4 (95% confidence limits) |
|---|---|---|
| V (unitless) | 1 (0.88, 1.12) | 1.0 (0.95,1.05) |
| K (pg/ml) | 899 pg/mL (435,1363) | 663 pg/mL (301, 1026) |
| c1 (for PCB 118) | 0.013 (4.5 × 10−3, 2.1 × 10−2) | 0.024 (0.0087, 0.039) |
| c2 (for PCB 126) | 1 (fixed) | 1 (fixed) |
| c3 (for PCB 153) | 0.00013 (4.2 × 10−5, 2.2 × 10−4) | 0.00021 (7.2 × 10−5, 3.5 × 10−4) |
| T0 for 14 weeks | 2.1 ng/dL (1.9,2.3) | 5.1 μg/dL (4.6,5.7) |
| T0 for 31 weeks | 2.2 ng/dL (2.0,2.3) | 4.0 μg/dL (3.6,4.5) |
| T0 for 53 weeks | 1.8 ng/dL (1.7,2.0) | 3.5 μg/dL (3.1,3.9) |
| β for 118 (pg/mL)−1 | 1.4 × 10−5 (7.0 × 10−6, 2.1 × 10−5) | 3.6 × 10−5 (2.0 × 10−5, 5.1 × 10−5) |
| β for 126 (pg/mL)−1 | 1.1 × 10−3 (5.8 × 10−4, 1.6 × 10−3) | 1.5 × 10−3 (7.0 × 10−4, 2.3 × 10−3) |
| β for 153 (pg/mL)−1 | 1.4 × 10−7 (7.5 × 10−8, 2.1 × 10−7) | 3.2 × 10−7 (1.9 × 10−7, 4.5 × 10−7) |