Population characteristics
| WTC-exposed male FDNY firefighters active on 9/11 | Male CFHS firefighters actively employed on 9/11 | |
| Total N | 10 786 | 8813 |
| Age on 9/11, mean±SD* | 40.4±7.5 | 43.9±9.2 |
| Race/ethnicity, N (%)* | ||
| Non-Hispanic white | 10 121 (93.8) | 6117 (69.4) |
| Non-Hispanic Black | 282 (2.6) | 1589 (18.0) |
| Hispanic | 353 (3.3) | 736 (8.3) |
| Other† | 30 (0.3) | 371 (4.2) |
| Smoking status, N (%)* | ||
| Current | 373 (3.5)‡ | 189 (6.6)§ |
| Former | 3233 (30.2)‡ | 1056 (37.0)§ |
| Never | 7117 (66.4)‡ | 1611 (56.4)§ |
| Military combat experience, N (%)* | 429 (4.1)¶ | 283 (9.9)§ |
| WTC site arrival time, N (%) | ||
| Exposure group 1 (highest): Morning of 9/11 | 1741 (16.1) | |
| Exposure group 2: Afternoon of 9/11 | 5683 (52.7) | |
| Exposure group 3: 12/9/2001 | 1873 (17.4) | |
| Exposure group 4: 13/9–24/9/2001 | 1315 (12.2) | |
| Exposure group 5 (lowest): After 24 September 2001 | 174 (1.6) | |
| Age at cancer diagnosis, median (IQR) | ||
| All cancers* | 55.6 (50.2–60.2) | 60.0 (54.4–64.8) |
| Prostate cancer* | 57.9 (53.3–62.4) | 60.4 (55.2–65.4) |
| Lung cancer | 60.4 (55.6–65.5) | 62.8 (57.9–67.2) |
| Kidney cancer | 56.0 (49.0–63.0) | 58.1 (54.7–63.2) |
| Non-Hodgkin lymphoma** | 53.6 (48.9–59.4) | 60.1 (50.1–65.3) |
| Melanoma (skin)* | 51.9 (45.5–57.8) | 61.2 (54.4–66.5) |
| Thyroid cancer** | 51.2 (44.0–56.5) | 59.0 (49.2–64.5) |
| Alive at end of follow-up, N (%)* | 10 525 (97.6) | 8208 (93.1) |
| Follow-up time (years), mean±SD* | 15.2±1.1 | 14.9±2.0 |
*P<0.001, **P<0.05.
†Includes Asian and Native American race categories.
‡N=10 723 who self-reported smoking status.
§N=2856 who completed CFHS survey.
¶N=10 429 who self-reported occupational history.
CFHS, Career Firefighter Health Study; FDNY, Fire Department of the City of New York; WTC, World Trade Center.