No animal studies have found an increased incidence of MM after exposure to the chemicals of interest. A summary of the biologic plausibility of the carcinogenicity of TCDD and the herbicides in general is presented at the end of this chapter. Chapter 3 discusses recent toxicologic studies that concern biologic plausibility.

There are insufficient data on MM in Vietnam veterans to draw a specific conclusion as to whether they are at increased risk.

There are four primary types of leukemia (ICD-9 202.4, 203.1, 204.0 –204.9, 205.0–205.9, 206.0–206.9, 207.0–207.2, 207.8, 208.0–208.9): the acute and chronic forms of lymphocytic leukemia and the acute and chronic forms of myeloid (or granulocytic) leukemia. According to ACS estimates, 17,600 men and 13,200 women will be diagnosed with some form of the disease in the United States in 2002, and 12,100 men and 9,600 women will die from it (ACS, 2002). Collectively, leukemias were expected to account for 2.5% of all new cancer diagnoses and nearly 4% of cancer deaths in 2002. The different forms of leukemia have different patterns of incidence and in some cases different risk factors. The incidences of the various forms of leukemia are presented in Table 6-48.

Acute lymphocytic leukemia (ALL) is a disease of the young and of people over 70 years old, and it plays a rather small role in the age groups that characterize most Vietnam veterans. The lifetime incidence of ALL is slightly higher in whites than blacks and in males than females. Exposure to high doses of ionizing radiation is a known risk factor for this form of leukemia; the evidence on other factors is inconsistent.

Acute myeloid leukemia (AML) is the most common acute leukemia among adults; its incidence increases steadily with age in people over 40 years old. In the Vietnam-veteran age groups, AML accounts for roughly one-fourth of cases of leukemia in men and one-third in women. Overall, AML is slightly more common in males than in females. White males have a higher incidence than white females; the lifetime incidence in black males and females is roughly equal. Risk factors associated with an increased risk of AML include high doses of ionizing radiation, occupational exposure to benzene, and some medications used in cancer chemotherapy (such as melphalan). Fanconi's anemia and Down syndrome are associated with an increased risk of AML, and tobacco-smoking has been suggested as a risk factor.

Chronic lymphocytic leukemia (CLL) is the most common of the four primary types of leukemia in men. Because CLL shares many traits with lymphomas

Front Matter (R1-R18)

Executive Summary (1-11)

1. Introduction (12-19)

2. Considerations in Evaluating the Evidence (20-29)

3. Toxicology (30-102)

4. Overview of Epidemiologic Studies (103-214)

5. Exposure Assessment (215-241)

6. Cancer (242-392)

7. Reproductive and Developmental Effects (393-446)

8. Neurobehavioral Disorders (447-476)

9. Other Health Effects (477-522)

10. Research Recommendations (523-528)

Appendix A: Agendas of Public Meetings (529-530)

Appendix B: ICD-9 Codes for Health Outcomes of Interest (531-533)

Appendix C: Committee and Staff Biographies (534-538)

Index (539-620)