Table 9 Microscopic findings in the tracheobronchial lymph nodes of male and female rats 24 h and 90 days after a 90-day exposure to Graphistrength^© C100

Target concentration (mg/m³)

0

0.05

0.25

5.0

0

0.05

0.25

5.0

Number examined

10/10

10/8

10/9

10/10

10/8

9/10

10/10

10/10

(24 h/90 days)

Black particle deposition

minimal

-

-

8/5

-

-

-

5/3

1

slight

-

-

-/2

6/3

-

-

-

7/1

moderate

-

-

-

4/7

-

-

-

1/9

Mean severity^a

-

-

0.8/0.9

2.4/2.7

-

-

0.5/0.3

1.8/2.9

Increased lymphocytes, cortex/paracortex

minimal

-

-

3/-

4/7

-

-

1/-

3/6

slight

-

-

-

3/2

-

-

-

7/-

moderate

-

-

-

3/-

-

-

-

-

Mean severity^a

-

-

0.3/-

1.9/1.1

-

-

0.1/-

1.7/0.6

Endothelial vacuolation, high endothelial venule

minimal

-

-

1/-

1/2

-

-

-

2/5

slight

-

-

1/-

7/1

-

-

-

5/-

Mean severity^a

-

-

0.3/-

1.5/0.4

-

-

-

1.2/0.5