26 BIOLOGICAL EFFECTS OF LOW LEVEL EXPOSURES
Figure 1.14. Gompertz plots for control and amosite asbestos-treated female F344/N
rats. Amosite asbestos administration (10,000 ppm feed) was begun at 8
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 the National Toxicology Program.95 Reprinted
from Neafsey et al.,24 p. 386, by permission of Marcel Dekker, Inc.
Figure 1.15. Gompertz plots for control and amosite asbestos-treated female 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. 387,
by permission of Marcel Dekker, Inc.