Chemicals, cancer, and risk assessment.

Cancer rates in Louisiana in particular, and the United States in general, especially as they relate to exposure to synthetic chemicals, have been a subject of great interest to the general public. Physicians are asked many difficult questions on this subject by their patients. This article provides an objective overview of cancer mortality rates and cancer risk assessment techniques with the intent of assisting physicians in providing knowledgeable responses to these questions. Prominent findings contained in this article include: (1) with the exception of lung cancer, due to consumption of tobacco products, cancer mortality rates are declining; (2) Louisiana ranks 16th among the 50 states in overall cancer mortality; (3) cancer risk assessment techniques used by the United States government are intentionally very conservative and overestimate real cancer risks, particularly for low level exposures; (4) the vast majority of cancers is related to individually controllable lifestyle factors; a small percentage is related to occupational or environmental exposures.

Smoking and roentgenographic opacities in US Navy asbestos workers.

The US Navy's Asbestos Medical Surveillance Program monitors civilian and military employees with current or historical exposure to asbestos. The prevalence of definite radiologic parenchymal abnormalities (ILO category greater than or equal to 1/0) was 3.10 percent for 32,233 smokers vs 1.09 percent for 13,414 nonsmokers. The age-adjusted prevalence ratio was 2.23. The difference in prevalence between smokers and nonsmokers persisted in all age groups studied and was greatest among the oldest employees. These findings in a large population suggest that parenchymal opacifications alone will not reliably differentiate between the impacts of asbestos exposure and smoking in patients who face both risks.

Roentgenographic evidence for predominant left-sided location of unilateral pleural plaques.

The roentgenographic prevalence and anatomic distribution of pleural plaques were studied in the US Navy Asbestos Medical Surveillance Program population (105,064 individuals as of July 17, 1985). "Definite" or "probable" pleural plaques were noted in 4.4 percent of films. These were unilateral in 19.3 percent of roentgenograms with "definite" pleural plaque and 33.9 percent of films with "probable" pleural plaque. Unilateral findings were more often left-sided than right-sided; a ratio of 287:82 in the "definite" group and 625:287 in the "probable" group. Left-sided predominance of unilateral plaque is a consistent and unexplained epidemiologic finding that may provide clues to pleural pathogenesis following asbestos exposure.

Retrospective analysis of Naval Special Boards of Flight Surgeons, 1974-83.

The Naval Special Board of Flight Surgeons was established in 1956 for the evaluation of Navy, Marine Corps, and Coast Guard problem aeromedical cases. This paper examines a sample 248 of these cases for the period of 1974-83 with respect to the characteristics of those referred, their referral diagnostic category, and the recommendation of the Special Board regarding return to a flying status. Those cases with a referral diagnostic category of ENT and Ophthalmology were less likely to be returned to flight status. Older, more senior pilots, and pilots with more total flight time were less likely to be returned to unrestricted flying than were their younger, more junior, and less experienced counterparts. Otherwise, no significant difference in outcome based on age, rank, marital status, branch of service, specialty, or flight hours was detected. Overall, 61% of those evaluated by the SBFS were returned to flight status.

Epidemiology and prevention of injuries.

Injuries are the leading cause of death for ages 1 to 44 and are responsible for more years of productive life lost than any other disease. The common perception of injuries as random, unpredictable events has impeded the application of existing knowledge and technology fully capable of preventing many injuries or lessening their severity. This article explores the concept of injury control, the application of standard epidemiologic methods of investigation, the identification of high-risk groups, and the development and implementation of strategies for trauma prevention.