US EPA

3085107 

Journal Article 

Secular changes in asbestosis in an asbestos factory 

Smither, WJ 

1965 

Yes 

Annals of the New York Academy of Sciences
ISSN: 0077-8923
EISSN: 1749-6632 

NIOSH/00192605 

132 

1 

166-181 

English 

5219546 

Cases of asbestosis in workers at a London asbestos (1332214) factory were compared with cases reported from the same site during the previous 30 years. Thirty cases of occupational asbestosis were reported in factory workers from 1930 to 1934, while a 1949 report described 28 cases at the factory. A report on 115 postmortem cases dated from the same year. A total of 26 cases were identified in a study in 1959, and another 26 were reported between 1960 and 1964. A series of 71 postmortem cases, appearing since 1957, was studied. Although the factory had been in operation since 1914, the first cases were reported in 1929, the year national asbestos regulations took effect. Dust exposure records were found to be inadequate for comparison over the years. Lengths of exposure before disability increased from a mean of 7 years (1930s) to a mean of 17.5 years for the 1960 cohort, indicating improved working conditions in spite of earlier case identification. Sputum was examined only in the earliest studies, demonstrating current disregard for diagnostic importance of expectorated asbestos bodies. Emphasis on various physical signs shifted over time, indicating longer exposure times as well as earlier diagnosis; in addition, shifting emphasis on various physiological tests reflected the incorporation of new diagnostic technologies. When the two postmortem series were compared, intrathoracic malignancy was higher (39.5 percent of deaths) in the later series than the earlier (14.8 percent). Mean survival times were longer in the later series (7.25 versus 6.4 years), and mean age at death was lower in the earlier series (40.8 versus 56.5 years). Tuberculosis became less important as a factor in mortality, appearing in only 5.6 percent of deaths in the 1957 series, as opposed to 31.3 percent in the earlier series. 

Index Medicus; Follow-Up Studies; Mortality; Thoracic Neoplasms -- epidemiology; Asbestosis -- epidemiology