Asbestos Medical Surveillance Program

Department of the Navy
Bureau of Medicine and Surgery

Navy ships had asbestos as the primary insulation around steam pipes (lagging) and boilers from the 1930's until the mid-1970's. Many of our service members may have had direct or indirect occupational exposures from past jobs or removal operations (ripouts). Some ships may still have asbestos present, much of which is nonfriable and, if left undisturbed, poses little health risk. Additionally, asbestos can be found in gaskets, brakes, clutches, older buildings, and roofing materials.

Shipboard personnel are instructed to report to the area supervisor or safety officer any whitish powder or

fine debris from frayed insulation or overheads. The identification of material as asbestos requires specific procedures. When in doubt, the material should be treated as asbestos until definitive identification is done.

Program guidance

References (a) through (c), listed at the end of this chapter, provide guidance on placement of personnel into the

Asbestos Medical Surveillance Program (AMSP), surveillance elements, forms, surveillance frequency, patient education, and administrative requirements. Reference (d) lists the specific exam elements and frequency for current and past asbestos workers based on years since first exposure. The Navy follows active service members and civilians even after their exposure to asbestos ceases, because the "latency" from time of initial exposure to time of development of asbestos-related-respiratory effect, often 15 years or more.

The medical officer (MO) places members into the AMSP and conducts or oversees the initial, periodic, and termination surveillance exams, x-rays ("B" reader films), and spirometry. The MO is often the AMSP manager on ship or in small facilities.

Personnel placement in the AMSP

MOs are often asked about placement of persons incidentally exposed to low levels of asbestos over a short time period (e.g., working in a space where asbestos was disturbed during routine maintenance) into the AMSP. The decision depends on prior exposures and the duration and level of the current exposure. In the absence of documented (i.e., measured) levels of current and/or possible future exposure above the medical surveillance action level defined by the Occupational Safety and Health Administration (OSHA), decisions about AMSP enrollment should be guided by the following principles:

Per reference (d), personnel may be included in the program, upon request, if any of the following criteria are met:

Consultation about asbestos exposure assessment and AMSP enrollment can be obtained from experienced industrial hygienists or occupational medicine physicians at any Naval Systems Commands (SYSCOMS), Military treatment facilities (MTFs), Navy Environmental Preventive Medicine Units (NEPMUs), or the Navy Environmental Health Center (NEHC).

Important Elements of the AMSP

• Chest X-ray ("B" Reader)
  A posterior to anterior (PA) view taken ata military treatment facility (MTF) certified to take AMSP films (most MTFs and a few larger ships) is required. The film is first read by a local radiologist before being 'batched' for reading by a NIOSH certified "B" reader who records the findings on the NAVMED 6260/7.

• Counseling
  Counsel the patient about the combined risk of smoking and asbestos exposure. Advise the patient to stop smoking if he or she currently smokes, and about available smoking cessation programs.

• Physicians' Written Opinion
  This is required for workers currently exposed to asbestos. It documents counseling on smoking, conditions that place a worker at increased risk of health impairment from asbestos exposure, limitations on use of personal protective equipment, and a statement that the employee has been informed by the physician of the results of the evaluation.

• Disclosures
  Discuss all asbestos-exposure-related findings (from NAVMED 6260/5 or 7) with the patient and document the discussion in the health record.

• Asbestosis is fibrosis of the lung parenchyma. This requires years of heavy exposure. The latency period is at least 15 years.

• Low-level short exposures to asbestos should not lead to asbestosis.

• Lung cancer risk is greatly increased in asbestos workers who smoke. A threshold level is not known. Latency period is about 25 years.

• Pleural plaques develop on the lining of the lung, not in the lung tissue. They do not develop into lung cancers or mesotheliomas and do not indicate future development of asbestosis. The latency period is at least 15 years.

• Mesotheliomas are rare tumors of the pleura of the lung. Small exposures can cause mesotheliomas and the latency period is 30-35 years.

• The change in lung volumes due to asbestosis is restriction (documented by lung volumes, not by just a low FVC). Obstructive changes are most often related to smoking.

• The "B" reader reads only the current film. Variations in film readings can occur from year to year because of inter-reader variability, the "B" reader reads only the current film, film quality, the subjectivity of pleural charges vs. pleural fat, and the low level of "profusion" that is consistent with fibrosis. When faced with a conflicting reading, consult with a radiologist or occupational medicine physician to review all of a worker's films.

References

1. Chapter B1 of OPNAVINST 5100.19 (Navy Occupational Safety and Health (NAVOSH) Program Manual for Forces Afloat), Volume 1.

2. Chapter 17 of OPNAVINST 5100.23 (Navy Occupational Safety and Health (NAVOSH) Program Manual for Shore Facilities).

3. LT Christian's Little Blue Book: An Unofficial Guide for U.S. Navy Shipboard Medical Officers. This is distributed to surface medical officers at the Surface Medical Officer Indoctrination Course (SWMOMIC). This reference can also be found under the administrative manuals on the Virtual Navy Hospital webstite at http://www.vnh.org/Admin/LittleBlueBook/Contents.html .

4. Navy Environmental Health Center, Technical Manual NEHC-TM-6260.96-1, change 1 (September 1998), Medical Surveillance Procedures Manual and Medical Matrix 6^th Edition).