The Tyler Asbestos Workers Program: I. A Medical Surveillance Model And Method

Our plain-English summary of The Tyler Asbestos Workers Program: I. A Medical Surveillance Model And Method, by G.A. Hurst, C.G. Spivey, W.T. Matlage, et al (1979).

The study

• Authors: G.A. Hurst, C.G. Spivey, W.T. Matlage, J.M. Miller, G. Faulk, L.R. Hieger, J.W. Mclarty, S.D. Greenberg
• Published: Archives Of Environmental Health 34(6):432-439, November-December (1979)
• Type of article: Journal article
• Our copy: from Johns-Manville's own medical library, J-M no. 001031. The article is still under copyright, so we describe it here rather than post it.

In plain English

This article described the Tyler Asbestos Workers Program, a medical checkup program funded by the National Cancer Institute and started on June 6, 1974. It covered former workers of an asbestos insulation plant in Tyler, Texas, which ran from 1954 until it closed in February 1972. The insulation was made of about 90% amosite asbestos. Government surveys found average fiber counts three to eighteen times the OSHA limit. As of May 31, 1978, the known group numbered 1,095 workers. Each worker was scheduled every 6 months for a questionnaire, physical exam, chest X-rays, breathing tests and sputum (coughed-up mucus) tests for cancer cells. People not exposed to asbestos were included to compare sputum results. Of workers examined in 1971, 85% reported a history of cigarette smoking, and seven met criteria for asbestosis. Sputum testing in the first year found squamous lung cancer in two of the workers screened (their number is unreadable in the scan); both died. Later, one worker and one smoker control had surgery for cancers not seen on X-ray. The authors said the study may help clarify the role of sputum testing.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Description of a medical surveillance program and its methods (protocol paper); results of the examinations were left for a later report
• Who was studied: Former workers of an asbestos insulation plant in Tyler, Texas (operated 1954 to February 1972). The cohort included 878 workers on a NIOSH master file, 52 more identified former employees, and 165 Manpower Incorporated workers who unloaded amosite. The total known cohort as of May 31, 1978 was 1,095 workers. A group of non-asbestos-exposed smokers and nonsmokers was added as a control for sputum cytology.
• Exposure: Amosite asbestos from the Transvaal, South Africa, used in insulation products (about 90% amosite mixed with diatomaceous earth, sodium silicate and wool). Surveys of five plant operations found mean fiber counts three to eighteen times the OSHA standard (maximum of five fibers longer than 5 microns per ml of air).
• Main results:
  • Each worker was given an appointment by mail every 6 months. The examination included a questionnaire, physical examination, chest roentgenograms, pulmonary function tests, sputum cytopathology (aerosol-induced and 3-day pooled specimens) and other laboratory tests. Workers with abnormal findings could be seen again immediately or placed on 3-month surveillance. The first worker was examined June 24, 1974.
  • In the data reviewed in January 1972 from the 1971 examinations, 85% of the workers indicated a history of smoking cigarettes.
  • Among the workers seen in that early review, seven fulfilled Murphy's epidemiologic criteria for the diagnosis of asbestosis.
  • The program's earlier preliminary cytology report covered first-year sputum findings in a group of workers whose number is unreadable in the scanned text. It found squamous carcinoma in two of those workers. Neither had resectional surgery, and both died.
  • Since that report, one worker (age 58) and one smoker control (age 67) with positive cytologies had localization and surgical resection for radiologically occult carcinoma. Their smoking histories were 60 and 50 packs/yr, respectively.
  • Eleven patients were admitted for diagnosis and treatment of known or suspected respiratory malignant disease.
  • Eighty-six percent of the program's workers were less than 40 years old when their employment began.
• The authors' conclusion: The authors stated that ample time appeared to be available to diagnose preinvasive or early invasive lung cancer by sputum cytopathology. They expected the greatest yield of early detection in the next 13 years. They said the serial study may help answer whether chest X-rays every 6 months are useful and clarify the role of cytology in a group at risk.

Topics

Medical terms in this study, explained in our Lexicon: Amosite, OSHA, Chest X-Ray, Sputum, Lung Cancer.

Browse return to medical research.