Table
23. Lung tumors induced in Fischer 344 rats by a single intratracheal
instillation of quartz
|
Treatment
sample and dose*
|
Sex
|
Observation
time
|
Incidence
of
lung tumors
|
Total
number
of lung
tumors
|
Histological
types
|
Number
|
%
|
Untreated:
|
No
dose |
M
|
Died
after 17 months
|
0/32
|
|
0
|
|
No
dose |
F
|
Died
after 17 months
|
1/20
|
5
|
1
|
1
adenoma |
Quartz
(Min-U-Sil 5):
|
12-mg
dose |
M
|
Sacrificed
at 11 months
|
3/18
|
17
|
37
|
6
adenomas,
25 adenocarcinomas, 1 undifferentiated carcinoma,
2 mixed carcinomas, and 3 epidermoid carcinomas |
Sacrificed
at 17 months
|
6/19
|
32
|
Died
after 17 months
|
12/14
|
86
|
12-mg
dose |
F
|
Sacrificed
at 11 months
|
8/19
|
42
|
59
|
2 adenomas,
46 adenocarcinomas, 3 undifferentiated carcinomas,
5 mixed carcinomas, and 3 epidermoid carcinomas |
Sacrificed
at 17 months
|
10/17
|
59
|
Died
after 17 months
|
8/9
|
89
|
20-mg
dose |
F
|
Died
after 17 months
|
6/8
|
75
|
13
|
1
adenoma,
10 adenocarcinomas,
1 mixed carcinoma, and 1 epidermoid carcinoma |
Quartz
(hydrogen fluoride-etched Min-U-Sil 5):
|
12-mg
dose |
M
|
Sacrificed
at 11 months
|
2/18
|
11
|
20
|
5
adenomas,
14 adenocarcinomas, and 1 mixed carcinoma |
Sacrificed
at 17 months
|
7/19
|
37
|
Died
after 17 months
|
7/9
|
78
|
12-mg
dose |
F
|
Sacrificed
at 11 months
|
7/18
|
39
|
45
|
1
adenoma,
36 adenocarcinomas,
3 mixed carcinomas, and 5 epidermoid carcinomas |
Sacrificed
at 17 months
|
13/16
|
81
|
Died
after 17 months
|
8/8
|
100
|
Sources:
Saffiotti et al. [1993; 1996].
*As mg quartz suspended in 0.3 ml saline.
Number of rats with lung tumors per number of rats
observed.
At all observation times.
|