Health Assessment Document for Diesel Emissions - NSCEP | US ...

1 In a similar study, 33 four-week-old male ICR mice per group were intratracheally
2 instilled weekly for 10 weeks with sterile saline, 0.1 mg DPM, or 0.1 mg DPM from which the
3 organic constituents were extracted with hexane (lchinose et al., 1997b ). Exhaust was collected
4 from a 2. 7 4 L four-cylinder Izuzu engine run at a steady speed of 2,000 rpm under a load of 6
5 torque (kg/m). Twenty-four hours after the last instillation, six animals per group were sacrificed
6 for measurement of 8-0HdG. Surviving animals were sacrificed after 12 mo. The incidence of
7 lung tumors increased from 3/27 ( 11.1%) among controls to 7/27 (25 .9%) among those instilled
8 with extracted diesel particles and 9/26 (34.6%) among those instilled. with unextracted particles.
9 The increase in number of tumor-bearing animals was statistically significant compared with
1 0 controls (p