James R. McCarroll

Atmospheric Pollutants and the Pathogenesis

Influenza-infected mice exposed continuously to 20 ppm of sulfur dioxide (SO2) for seven days after virus exposure developed more pneumonia than virus control mice. Dose-response experiments suggested that the post virus SO2-induced increase in influenzal pneumonia began at about 7 to 10 ppm. The increase in pneumonia was not influenced by altering the virus dosage within a 5 to 100 mouse infectious dose range. A similar increase (15% to 20%) in influenzal pneumonia was observed when mice were exposed to 25 ppm of SO2 prior to initiation of virus infection. The SO2 exposure had no effect on the growth of influenza virus in the lungs of mice. Rather, the increase in She amount of pneumonia was associated with SO2 concentrations which induced low-grade, inflammatory lesions in the lung.

Health and the Urban Environment: Health Profiles Versus Environmental Pollutants

The organization and early findings of a study of the effects of air pollution on a group of New York City residents are reported. A preliminary analysis indicates reaction patterns and possible etiologic factors. Methods of a more discriminating analysis may permit identification of unsuspected effects upon health.

HEALTH AND THE URBAN ENVIRONMENT. AIR POLLUTION AND FAMILY ILLNESS. I. DESIGN FOR STUDY.

A survey was undertaken on Manhattan Island, New York, in order to study the relationship of air pollution episodes and pulmonary diseases in a group of city dwellers. The investigation involved simultaneous monitoring of the environment with the health of the people. The goal was to follow daily variations in health of a group of urban families of diverse backgrounds living in the same geographic area and to correlate these over a period of time with variations in the atmosphere to which they were exposed.

Health and the urban environment

The effect of each of several pollutants on the health of urban families on the lower East Side of Hew York city has been assessed. Prevalence of certain symptoms on one day of the week (Monday) was assessed according to level of each pollutant (low, medium, or high). Prevalence was treated as a binomial variable (number of “yes” responses/number of “yes” and “no” respouses) whereas pollutant level was a continueous variable (but ordered, by thirds), according to the method of Armitage. In summer, in children under 8 years of age, prevalence of respiratory symptoms was directly related to increasing levels of particulate matter and of carbon monoxide. In heavy smokers, prevalence of eye irritation and headache was directly related to increasing levels of carbon monoxide.