Health Effects of Exposure to High Concentrations of Automotive Emissions

On-site and remote health evaluations were performed on 550 employees of the Triborough Bridge and Tunnel Authority in New York City. Extremely high ambient air pollution was observed. Carbon monoxide averaged 63 ppm over a 30-day period with a maximum hourly concentration of 217 ppm in one facility. Eighty-five percent of the smoking and 47% of the nonsmoking tunnel workers had carboxyhemoglobin saturations in excess of 3%. A high percentage of the group had symptoms suggestive of chronic bronchitis; airway resistance was elevated in one third and almost all bridge and tunnel workers had an increase in closing volume, suggesting small airway disease.     

In Vitro Alveolar Macrophage Viability

A simple, rapid method was developed for the determination of in vitro alveolar macrophage viability after exposure to gases. Air pollutants such as ozone, sulfur dioxide, and oxides of nitrogen killed alveolar macrophages, as determined by the dye exclusion test. Ozone (O₃) was effective at very low concentrations. Other gases such as carbon dioxide (CO₂), carbon monoxide (CO), methane (CH₄), methyl chloride (CH₃Cl), acrolein, acetaldehyde, acetone, isoprene, benzene, and hydrocyanic acid (HCN) had no effect on cell viability.     

Age,Smoking Inhalation,and Pulmonary Function

? This study examined the relative effects of age and smoking on pulmonary function. Smoking was measured by six smoking variables, taken singly and as a composite. Subjects were 1,510 male participants in the Normative Aging Study. A stepwise multiple regression with vital capacity (VC) and forced expiratory volume at one second (FEV_1.0) as the criteria accounted for 24.4% and 28.3% of the variance, respectively. Two-way analyses of variance showed that the age decline in pulmonary function was substantially greater for high inhalers than it was for low inhalers or nonsmokers. Age and the inhalation index were also noticeably and independently related to a decline in pulmonary function.     

The Lead Content of Teeth

? Teeth were collected from populations differing in their degree of industrialization and from prehistoric populations. Lead analysis of dentine revealed that in contemporary teeth the lead level was related to the degree of industrialization and that in prehistoric teeth very low concentrations of lead were present. Because tooth lead reflects the body burden of lead this result suggested that the prehistoric populations and modern nonindustrial populations were exposed to environments low in lead. Teeth from a contemporary population of nonindustrialized Indians of the Lacandon forest in Mexico contain lead in concentrations comparable with those of the prehistoric populations. Comparison of the Indian teeth with teeth from a modern industrial population reveals a 45-fold difference in median tooth lead level. This finding lends support to the hypothesis that high levels of urban lead pollution result in elevated body burdens of lead.     

Smoking and Carboxyhemoglobin in the St. Louis Metropolitan Population

The most important source of carbon monoxide (CO) exposure is smoking. If a person smokes and inhales, the carboxyhemoglobin (COHb) level in his blood is due primarily to smoking, and other sources of CO exposure are relatively unimportant. The COHb data for smokers are analyzed by type of smoking, sex, and whether or not the subject has an industrial occupation. Data indicate that men and women who smoke at the same rate reach the same equilibrium level of COHb, but women achieve lower COHb levels after ceasing smoking for the day. Restriction or elimination of cigarette smoking makes the most sense for protecting the atherosclerotic population from chronic CO exposure.