HYPOTHESES ON LONGEVITY HORMESIS 27Figure 1.16. Gompertz plots for control and amosite asbestos-treated male Syrian
golden hamsters. Amosite asbestos administration (10,000 ppm feed) was
begun at 10 weeks of age and continued throughout life. Time on the
abscissa refers to the period following initiation of exposure. The theoretical
lines were obtained by simultaneous fitting of Equations 3 and 12,
employing weighted least-squares regression analysis. Both longevity
hormesis and irreversible toxicity are evident. The original data came from
the National Toxicology Program.96 Reprinted from Neafsey et al.,24 p. 388,
by permission of Marcel Dekker, Inc.
Figure 1.17. Gompertz plots for control and dieldrin-treated male CF-1 mice. Dieldrin
administration (1 ppm feed) was begun at 4 weeks of age and continued
throughout life. Time on the abscissa refers to the period following initiation
of exposure. Although the data are consistent with concomitant longevity
hormesis and toxicity, and this model was used in the curve-fits, the figure is
equivocal in making a more definitive judgment. The theoretical lines were
obtained by simultaneous fitting of Equations 3 and 12, employing weighted
least-squares regression analysis. The original data came from Walker et
al.97 Reprinted from Neafsey et al.,24 p. 389, by permission of Marcel
Dekker, Inc.