Abstract
Pulmonary parameters including tidal volume, respiratory rate, minute volume, pulmonary flow resistance, dynamic compliance of the lung, and the work of breathing were measured in unanesthetized cynomolgus monkeys. A small group of animals was tested frequently during a period of 78 weeks and regression analysis of the data, including calculations of confidence limits, provided an estimate of the variation and trends in the above parameters. A digital computer technique, which was used for real-time data analysis of the recorded analog signals, was developed to elucidate the effects of long-term exposure to low levels of pulmonary irritants and urban atmospheric pollutants, such as sulfur dioxide and nitrogen dioxide.