John F. Gamble

Epidemiological-environmental study of diesel bus garage workers: Acute effects of NO2 and respirable particulate on the respiratory system

Personal samples of nitrogen dioxide (NO2) and respirable particulate (RP) were collected over the shift on 232 workers in four diesel bus garages. Response was assessed by an acute respiratory questionnaire and before and after shift spirometry. Measures of exposure to NO2 and RP were associated with work-related symptoms of cough; itching, burning, or watering eyes; difficult or labored breathing; chest tightness; and wheeze. The prevalence of burning eyes, headaches, difficult or labored breathing, nausea, and wheeze experienced at work were higher in the diesel bus garage workers than in a comparison population of battery workers, while the prevalence of headaches was reduced. Mean reductions in forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), peak flow, and flows at 50 and 75% of FVC were not obviously different from zero. There was no detectable association of exposure to NO2 or respirable particulate and acute reductions in pulmonary function. Workers who often had respiratory work-related symptoms generally had a slightly greater mean acute reduction in FEV1 and FEF50 than did those who did not have these symptoms, but these differences were not statistically significant.

Epidemiological-environmental study of lead acid battery workers: III. Chronic effects of sulfuric acid on the respiratory system and teeth

The effects of long-term exposure to sulfuric acid mist on the teeth and respiratory system were studied in 248 workers in five plants manufacturing lead acid batteries. The prevalence of cough, phlegm, dyspnea, and wheezing as determined by questionnaire were not associated with estimates of cumulative acid exposure. There was only one case of irregular opacities seen on the chest radiographs. There was no statistically significant association of reduced FEV1, peak flow, FEF50, and FEF75 with acid exposure although the higher exposed group had lower mean values. FVC in the high exposure group showed a statistically significant reduction compared to the low exposure group, but there was no significant association when exposure was analyzed as a continuous variable. The ratio of observed to expected prevalence of teeth etching and erosion was about four times greater in the high acid-exposure group. The earliest case of etching occurred after 4 months exposure to an estimated average exposure of 0.23 mg/m3 sulfuric acid.

Knuckle pads in live‐chicken hangers

A study of live‐chicken hungers in a poultry processing plant demonstrated a high prevalence of callosities over the knuckles (knuckle pads)of both hands, Knuckle pads were observed in 56% (23/41) of live‐chicken hangers, but in no (0.41)workers from other departments (p<0.001)The probable cause was the repeated striking and sliding of knuckles against metal shackles in which live birds were being plated. Additional medical and ergonomic evaluation would be worthwhile to confirm the cause, to determine whether associated tissue disorders are present in the digits of chicken hangers who develop knuckle pads, and to suggest preventive measures.

Epidemiological-environmental study of lead acid battery workers. II. Acute effects of sulfuric acid on the respiratory system.

Two hundred and twenty-five (225) workers in five lead acid battery plants were administered a questionnaire containing work-related symptoms, underwent spirometry, and had personal samples for H2SO4 taken over the shift. Most personal samples were less than 1 mg/m3 H2SO4. Mass median aerodynamic diameter of H2SO4 from area samples in the formation areas was 2.6-10 micron. Workers with a higher exposure to acid did not have an increased rate of acute work-related symptoms. Changes in pulmonary function over the shift were not related to levels of airborne lead or airborne acid, sex, age, or smoking status. In acclimated workers, there is no evidence of acute symptoms or reductions in pulmonary function over the shift at concentrations less than 1 mg/m3.

Letter to the editor on commentary: Malignant mesothelioma incidence among talc miners and millers in New York state by MM finkelstein

(1) Mesothelioma has been diagnosed among members of the cohort at a rate in excess of that in the general population. (2) Fibers of tremolite and anthophyllite have been detected in dust and the lungs of talc workers. (3) These fibers are known causes of mesothelioma. It is prudent, on the balance of probabilities, to conclude that dusts from NYS talc ores are capable of causing mesothelioma in exposed individuals.

The role of the lung in stomach carcinogenesis: A revision of the Meyer hypothesis

Meyer et al. present an hypothesis postulating an essential opposition between lung cancer and stomach cancer based upon the interaction between cigarette smoking, respiratory impairment, and exposure to airborne carcinogens. Their theory is that respiratory impairment serves as a gate to determine whether carcinogenic airborne particulate is retained in the lungs to produce lung cancer or is cleared and swallowed to produce stomach cancer. This paper examines the foundations of the Meyer hypothesis, identifies particle deposition patterns as a crucial Meyer omission, and presents a reformulated theory based upon both particle deposition and particle retention.

Reply to Kunzli and Tager Regarding Causality in PM2.5 Cohort Studies.

pollution epidemiology: a valid design as compared to ecologic studies. Environ Health Perspect 105:1078-1083 (1997). 3. Brenner H, Savitz D, Joeckel K, Greenland S. Effects of nondifferential exposure misclassification in ecologic studies. Am J Epidemiol 135(1):85-95 (1992). 4. Greenland S. Divergent biases in ecologic and individual-level studies. Stat Med 11:1209-1223 (1992). 5. Wacholder S. When measurement errors correlate with truth: surprising effects of nondifferential misclassification. Epidemiology 6(2):157-161 (1995). 6. Navidi W, Thomas D, Stram D, Peters J. Design and analysis of multilevel analytic studies with applications to a study of air pollution. Environ Health Perspect 102(suppl 8):25-32 (1994). 7. Abbey D, Moore J, Petersen F, Beeson L. Estimating cumulative ambient concentrations of air pollutants: description and precision of methods used for an epidemiologic study. Arch Environ Health 46(5):281-287 (1991). 8. Dockery D, Pope A, Xu X, Spengler J, Wae J, Fay M, Ferris BJ, Speizer F. An association between air pollution and mortality in six U.S. cities. N EngI J Med 329(24):1753-1759 (1993). 9. KOnzli N, Lurman F, Segal M, Ngo L, Balmes J, Tager I. Association between lifetime ambient ozone exposure and pulmonary function in college freshman-results of a pilot study. Env Research 72(1):8-23 (1997). 10. Ashley F, Kannel W, Sorlie P, Masson R. Pulmonary function: relation to aging, cigarette habit, and mortality; the Framingham Study. Ann Internal Med 82:739-745 (1975). 11. Neas LM, Schwartz J. Pulmonary function levels as predictors of mortality in a national sample of US adults. Am J Epidemiol 147(11):1011-1018 (1998). 12. Ackermann-Liebrich U, Leuenberger P, Schwartz J, Schindler C, Monn C, Bolognini G, Bongard J, Brindli 0, Domenighetti G, Elsasser S, et al. Lung function and long-term exposure to air pollutants in Switzerland. Am J Respir Crit Care Med 155(1):122-129 (1997). 13. Neas L, Hoek G, Dockery D. Air pollution and the incidence of adult pulmonary function deficits in six US cities [abstract]. Epidemiology 9(4):S160 (1998). 14. Rothman KJ. Modern Epidemiology. Boston/ Toronto:Little, Brown and Company, 1986.

Response to loomis et al

ImagesFigure 1