This proposal will try to settle the question whether low level granite dust exposure in the Vermont Granite Industry leads to adverse effects on worker health, as judged by longitudinal measurement of pulmonary function, the presence of radiographic abnormalities on chest films or the prevalence of chronic respiratory symptoms. These issues are very much indoubt. Previously published work which suggested that harmful health effects occur may have been in error. Serial measurements of pulmonary function will be compared with previous estimates of loss. A chest x-ray survey will establish the prevalence and type of abnormalities in the work force. Using radiographs taken in surveys since 1939, we will establish the desirable interval at which survey films should be taken. As a basis for comparison, the loss of pulmonary function and prevalence of chronic respiratory symptoms will be measured in a control group of non-dust exposed Vermont workers. Spirometric measurements, radiographic interpretations and questions regarding symptoms will observe the recently recommended standards published under the auspices of the ATS/DLD. Random sampling and analysis of total and quartz dust will be carried out using size-selective personal samplers: quartz will be analyzed using the infrared spectrophotometry method. Two important subsidiary questions will be examined: 1) the rate of pulmonary function loss in retired workers with radiographic silicosis, and 2) the extent to which chest films become more abnormal after dust exposure stops. The ultimate purpose of the proposal is to establish whether the more stringent standards proposed in a recent cirteria document for quartz dust exposure is in fact necessary to protect worker health.
