Showing papers in "Journal of Occupational and Environmental Medicine in 1986"

Lung cancer screening: the Mayo program.

Abstract: The National Cancer Institute has sponsored three randomized controlled trials of screening for early lung cancer in large, high-risk populations to determine whether lung cancer detection can be improved by adding sputum cytological screening every 4 months to chest roentgenography done either yearly or every 4 months; and lung cancer mortality can be significantly reduced by this type of screening program, followed by appropriate treatment. Results of the three trials suggest that sputum cytology alone detects 15% to 20% of lung cancers, almost all of which are squamous cancers with a favorable prognosis; and chest roentgenography may be a more effective test for early-stage lung cancer than previous reports have suggested. Nevertheless, results of the randomized trial conducted at the Mayo Clinic showed that offering both procedures to high-risk outpatients every 4 months conferred no mortality advantage over standard medical practice that included recommended annual testing.

Observations on the healthy worker effect.

Abstract: Follow-up mortality data from ten groups of employed persons are compared to the mortality rates of the United States general population. Comparisons related to the healthy worker effect (HWE) are computed. As measured by a relative comparison, the standardized mortality ratio (SMR), the HWE is seen to have a dynamic phase and a plateau phase in relation to length of follow-up. In contrast, the HWE as measured by an absolute comparison has little relationship to length of follow-up. Age at entrance into follow-up is strongly related to the absolute risk of mortality, but has little or no relation to the relative risk (SMR). Issues related to the evaluation and minimization of the healthy worker effect are discussed.

A preliminary investigation: effect of a corporate fitness program on absenteeism and health care cost.

Abstract: A random sample of 517 employees was studied to determine differences in health care costs and absenteeism among exercisers and nonexercisers during the start-up of a corporate health and fitness program. Exercise was associated with decreased illness absence among female exercisers (47 v 69 hours, P less than .05) and there was a trend for illness absence to be inversely related to advancing age among exercisers, whereas illness absence increased among nonexercisers. Total health care costs among exercisers was lower (male $561, females $639) than among nonexercisers (male $1,003, females $1,535). Due to the large variation in the individual cost, the differences between exercisers and nonexercisers were not statistically significant. Ambulatory health care cost for nonexercisers (males $486, females $883) were significantly higher than the costs for exercisers (males $408, females $243). Because the differences were found upon program initiation, they were thought to be characteristics of exercisers and not due to exercise itself.

Biological monitoring of agricultural workers exposed to pesticides: I. Cholinesterase activity determinations.

Abstract: An estimated 4 to 5 million persons work in agriculture; within this sector, mixers, loaders, applicators, and other workers who directly handle agricultural chemicals are at highest risk for pesticide-related illnesses. Among field workers, seasonal workers engaged in certain cultivation and harvesting operations are also at risk of exposure to pesticide residues. Biological screening for agricultural workers is limited at present to pesticide mixers, loaders, and applicators, and consists almost exclusively of measurements of cholinesterase activity to estimate inhibition by organophosphate and carbamate compounds. We review here the measurement and interpretation of cholinesterase activity in occupationally exposed populations and the correlation between cholinesterase activity and symptoms of acute and chronic illness among agricultural workers. The only state to mandate medical surveillance for agricultural workers is California: criteria for surveillance, baseline cholinesterase determination, periodicity of testing, and criteria for removal from and return to work are described, and alternative approaches for screening and clinical evaluations are discussed.

Energy costs of simulated stair climbing as a job-related task in fire fighting.

Abstract: The purpose of this investigation was to determine the energy requirement of simulated stair climbing. Metabolic costs of climbing stairs in getting to the scene of a fire can be very demanding for fire personnel. Heart rate and oxygen consumption were measured on 17 fire fighters during each of three conditions: (1) stair climbing without fire-fighting uniform or equipment, (2) stair climbing with fire-fighting uniform and equipment, and (3) pedaling a bicycle ergometer in a graded maximal exercise test. These three conditions were designed to determine (1) baseline reference values, (2) actual work task measures, and (3) maximum reference values. Results showed that climbing stairs with an 8-inch rise at 60 steps per minute with fire fighter's uniform and equipment (86.5 pounds) for five minutes required heart rates to reach 95% (84 to 100) of maximum effort, and oxygen consumption measures were found to be 80% (63 to 97) of maximum. It was concluded for the personnel studied that the rate of energy cost of climbing a simulated staircase with uniform and equipment required an ability to consume at least 2.7 L of oxygen per minute and 39 mL/kg/min.

Cumulative exposure to arsenic and its relationship to respiratory cancer among copper smelter employees.

Abstract: To explore the role of arsenic as a human carcinogen, the respiratory cancer mortality experience (1938 to 1977) of 8,045 while male smelter employees in Montana was examined relative to cumulative exposure to arsenic trioxide and was compared with that of the white male population of the same region. Exposure to arsenic was estimated for various work areas from industrial hygiene reports of average concentrations present in the smelter. Respiratory cancer mortality was analyzed further by time period of first employment and maximum lifetime exposure to arsenic trioxide. When exposure was estimated with arithmetic means of measured concentrations among men first employed prior to 1925, respiratory cancer mortality increased linearly with increasing cumulative exposure group, ranging from two to nine times expected; among those first employed in the period 1925 to 1947 it also increased linearly with increasing cumulative exposure group.

Sputum cytopathology: use and potential in monitoring the workplace environment by screening for biological effects of exposure.

Abstract: Sputum cytopathologic monitoring detects squamous cell lung cancers at an extremely early stage (x-ray negative). It holds further potential for preventing disease by detecting epithelial alterations which reflect environmental hazards. The addition of sputum cytology screening to screening by chest x-ray film does not significantly reduce mortality from all types of lung cancer, but preliminary analysis of Johns Hopkins Lung Project data suggests that mortality from squamous cell carcinoma is reduced. Quantitative automated cytopathology systems and biochemical/immunological cell markers enhance understanding of these precursors and offer great promise for increasing capacity, accuracy, and usefulness in cytopathology screening of workers. Cytological specimens collected over years of screening workers considered at risk may be important to eventually understanding development and prevention of major occupational diseases.

Biological monitoring of agricultural workers exposed to pesticides: II. Monitoring of intact pesticides and their metabolites.

Abstract: Analytical methods have been developed for the detection of a variety of compounds that are found intact or as metabolites in biological samples from workers exposed to pesticides. Such tests are used primarily in research settings to describe patterns of absorption, metabolism, and excretion, to derive exposure limits for occupational exposure, to evaluate the adequacy of these limits and of work practices in field settings, and to confirm the etiology of poisonings for medicolegal purposes. We review here methods used in studies of occupational pesticide exposure, with particular attention to validation in terms of dose-response relationships, to technical complexity and cost, to the requirements for analytical quality control, and to the utility of these methods for field research purposes. Biological monitoring for intact pesticides or metabolites in agricultural workers is limited to a few chemicals, notably, pentachlorophenol, methyl bromide, and chlordimeform. These programs and their use in regulation and enforcement are described.

New screening device for assessment of peripheral neuropathy.

Abstract: Screening for the onset of toxic and entrapment neuropathy is a major concern in occupational medicine today. Current perception thresholds may be used as a measure of the integrity of the peripheral nervous system. A new transcutaneous nerve stimulator was used to evaluate current perception thresholds in 54 normal persons and 33 diabetic subjects. Current perception thresholds in the normal volunteers with no evidence of peripheral neuropathy were found to vary significantly with the frequency and location of the stimulation, as well as age. The test identified the diabetic peripheral neuropathy with an overall sensitivity of 94%. This new diagnostic technique is quick, simple to perform, noninvasive and nonaversive and provides a sensitive quantitative measure of sensory function. This diagnostic stimulator will be useful for screening occupationally related toxic and entrapment neuropathies in which sensory impairment is an early finding.

Detection of cumulative trauma disorders of upper extremities in the workplace.

Abstract: Surveillance for musculoskeletal disorders of the upper extremity in industry is in its infancy. Research efforts to elucidate the causal factors of these disorders often rely on either the analysis of existing medical records, worker compensation records (passive surveillance), or the surveying of workers with questionnaire and physical examination (active surveillance). The use of either type of data for routine surveillance presents several difficulties illustrated with the results presented in this paper. The analysis of existing records is generally less costly but the reliability of the data is difficult to assess. Standardized questionnaire and physical examinations can be as sensitive as the use of unusually thorough existing occupational medical records; however, it is unclear whether the additional cost of an active surveillance system will deter the routine use of such systems.

Effects of a corporate health promotion program.

Abstract: The effects of a pilot health promotion program at ATT a second control group was neither given the health risk appraisal nor offered modules. The health promotion program was found to lower health risks and improve health-related and job-related attitudes among the study group. Participants in specific intervention modules experienced gains in positive health behaviors.

Risk factors for occupational hand injury.

Abstract: A case-control study of occupational hand injury was conducted in an effort to identify risk factors for disabling injury. Case employees in this study were municipal employees who had sustained restricted activity or lost work time as a result of hand injuries while at work. Each case employee was individually matched to a control employee of the same sex who held the same job and was at work on the same date and shift that the case employee's injury occurred. A conditional logistic regression model was used to adjust for confounding variables. Performing a task that was not a usual job requirement, using defective materials, presence of cardiovascular disease, sleeping nine or more hours per night, and being less than 25 years of age were identified to be risk factors after adjustment. Language: en

Organic solvent-induced encephalopathy in industrial painters.

Abstract: Although organic solvents are essential components of an industrial economy, they are not used without risk. The relationship between excessive exposure to organic solvents and subsequent development of chronic encephalopathy has been recognized for nearly 100 years. Fifteen industrial painters who underwent evaluation in an occupational health clinic for symptoms that they related to their work were found to have a high prevalence of neurasthenic symptoms, most frequently, memory loss and personality change. Although neurologic and screening laboratory examinations showed no consistent abnormalities, psychological tests documented poor short-term memory and an array of neuropsychologic deficits. Personality profiles revealed depression, anxiety, and preoccupation with somatic concerns. These findings agree well with previous reports of "chronic painter's syndrome." Heightened awareness among industrial physicians and prospective studies to evaluate existing threshold limit values and personal protective equipment requirements are indicated.

Interaction between tobacco smoking and occupational exposures in the causation of lung cancer.

Abstract: The nature of the interaction between smoking and occupational exposure is controversial, in part because of lack of agreement on the definition of interaction and in part because of the scarcity of adequate epidemiologic data. Occupational investigators have assessed interaction primarily as a departure from an additive rather than from a multiplicative model of relative risks (or rate ratios). To determine whether smoking modifies the effect of occupational lung carcinogens, the literature was reviewed for the only four established occupational lung carcinogens for which there are data on smoking: radon daughters, asbestos, arsenic, and chloromethyl ethers. Where possible, departure was assessed from both an additive (synergism) and a multiplicative model (effect modification). Only nine studies were considered to have sufficient sample size and to provide sufficient information on tobacco use and occupational exposure to evaluate interaction. The existing data were contradictory for three of the agents studied: asbestos, radon daughters, and arsenic. Inconclusive or contradictory findings may result from small sample size or lack of comparability of the level of occupational or tobacco exposure. It is noteworthy that, for these four agents, whenever smoking did modify the effect of occupational exposure, the lung cancer rate ratio was greater for nonsmokers (compared to nonexposed nonsmokers) than smokers (compared to nonexposed smokers). However, with the exception of chloromethyl ethers, absolute lung cancer rates were higher for smokers than nonsmokers, regardless of occupational exposure.

Neurobehavioral testing in monitoring hazardous workplace exposures.

Abstract: Exposure to workplace toxins, particularly organic solvents, lead, and pesticides, has been shown to cause both transient and persistent derangements of CNS function. Neurobehavioral testing is described as a means of evaluating the health effects of exposure to toxic chemicals. The use of neurobehavioral testing is most appropriate where an exposure has been characterized and the diseases of interest specified. Most investigators use batteries of tests to evaluate psychomotor function, memory, verbal ability, mood, and visual/spatial abilities. Because of the shortcoming of the interviewer-administered test batteries, existing neurobehavioral tests have been adapted to a computer-administered format. This tool offers promise for future efforts to monitor CNS function in exposed workers.

Occupational exposure monitoring using breath analysis.

Abstract: Breath analysis has been proposed on numerous occasions for monitoring solvent exposure. Nevertheless, it is still rarely used routinely because of difficulties in the methodology itself (sampling and analysis) and lack of data concerning its relationship to exposure dose. The various methods available today are briefly reviewed, compared, and discussed. Emphasis is on the simultaneous use of CO2 as a respiratory index. Two methods using this approach are presented. The advantages and limitations of breath analysis for occupational exposure monitoring are discussed using data obtained in experimental, field, and simulation studies. Benzene toluene, styrene, 1,1,1-trichloroethylene, and tetrachloroethylene are taken as examples of solvents showing various toxicokinetic properties. Finally, breath analysis is compared with other biological monitoring methods.

Medical screening in the workplace: proposed principles.

Abstract: Medical screening and biological monitoring are two techniques in a continuum of practices used to prevent occupational disease. Medical screening is the examination of workers for pathological conditions. Biological monitoring is the examination of the worker for the presence of an intoxicant or its metabolite. These techniques are common in industry, and are frequently components of health standards recommended by the National Institute for Occupational Safety and Health (NIOSH) to the Occupational Safety and Health Administration. However, an underlying set of principles for medical screening and biological monitoring in the workplace has not been delineated. In this paper, a modification of the principles for screening in the community is proposed that will be more appropriate to the workplace. This modified set of principles is not a statement of the policy of NIOSH on this important subject, but rather a presentation of the authors' views as a starting point for dialogue on these issues.

Update of a mortality study of workers in petroleum refineries

Abstract: A large cohort of petroleum refinery workers with long duration of employment, long latency, and relatively young age at hire had its vital status updated through Dec. 31, 1980. The standardized mortality ratio (SMR) for all causes was 78. Each nonneoplastic cause had an SMR below 100, including SMRs of 63 for emphysema and for all diseases of the genitourinary system and of 73 for chronic nephritis. The SMR for all cancers was 87. SMRs for specific neoplasms included digestive system, 90; lung, 85; kidney, 68; brain, 89; leukemia, 101; multiple myeloma, 123; unspecified lymphoma, 112; polycythemia vera (four deaths), 455; myelofibrosis (three deaths), 201; and benign and unspecified brain neoplasms, 108. There were nine deaths from mesothelioma; all nine employees had more than 20 years of employment, with an SMR of 241.

Cancer mortality among white males in the meat industry.

Abstract: A study was conducted among 13,844 members of a meat-cutter's union, from July 1949 to December 1980, to examine cancer occurrence in the meat industry. Separate analyses were carried out for the whole group, and for subgroups defined by job-categories characteristic of the industry, including a control group. Mortality was compared with that of the United States through the estimation of standardized mortality ratios (SMR) and proportional mortality ratios. A statistically significant proportional mortality ratio of 2.9 was obtained for Hodgkin's disease among abattoir workers; the SMR of 2.2 was not significant. Among meat-packing plant workers, highly statistically significant SMRs were recorded for bone cancer, SMR = 9.6; cancer of the buccal cavity and pharynx, SMR = 3.4; and lung cancer, SMR = 1.9. The role of oncogenic viruses and other carcinogenic exposures was investigated.

Seven-year follow-up of workers exposed to 1,2-dibromo-3-chloropropane.

Abstract: A follow-up report was done of workers exposed to 1,2-dibromo-3-chloropropane (DBCP) 7 years after termination of exposure. A 1977 study of male pesticide workers exposed to DBCP in a California agricultural chemical plant identified many who were azoospermic or oligospermic. Sperm concentration and serum follicle-stimulating hormone (FSH) levels in 44 of these workers were reassessed 5 to 8 years after exposure was terminated in 1977. Two of the eight originally azoospermic workers produced sperm during the follow-up, although only one had normal sperm counts. No increase in sperm production could be detected in men who had low sperm counts in 1977, and elevated serum FSH levels did not drop in oligospermic or azoospermic men. These results suggest that permanent destruction of germinal epithelium occurs in most DBCP-sterile persons.

Spontaneous abortion and occupation.

Abstract: Occupational factors in spontaneous abortion were studied in the current and previous pregnancies of 56,012 women interviewed in 11 Montreal maternity departments, 1982 to 1984. Ratios of observed to expected abortions (RR), after allowance for nonoccupational confounders, were significantly increased (P less than .05) among nursing assistants and attendants (RR 1.24 in current and 1.13 in previous pregnancies), food and beverage servers (RR 1.31 in current and 1.11 in previous pregnancies) and sales persons (RR 1.18 in current and 1.12 in previous pregnancies). Women whose work entailed heavy lifting, other physical effort, long hours, exposure to noise, and exposure to cold had also significantly increased risk ratios. However, when occupational groups were ranked according to work demands, thus avoiding potential bias from prior knowledge of outcome, increased risks were associated consistently only with heavy lifting and other physical effort.

Health aspects of work with visual display terminals

Abstract: Visual display terminals (VDTs) are in widespread and continuously increasing use by a large number of people. Several physical factors may affect an operator's performance and health. These include visual factors such as display characteristics, image quality, resolution, stability, color, polarity, luminance, and contrast, as well as lighting conditions and indoor climate. Work station design and layout play the most critical role in eliminating sources of postural problems. Exposure of the operators to various radiations that may be produced by VDTs is not expected to have any health implications, as the levels of emissions are very low. Musculoskeletal effects and visual fatigue can usually be successfully controlled through proper design and use of work stations.

Correction of urinary mercury concentration by specific gravity, osmolality, and creatinine.

Abstract: Corrections for specific gravity, osmolality, and creatinine were applied to identical urinary mercury data in order to investigate the reproducibility of the corrected mercury concentration in a person's urinary spot samples throughout a 24-hour period; and the extent to which it is possible to predict a person's 24-hour mercury excretion from the corrected mercury concentration in the corresponding spot samples. The data indicate that on the average these corrections improve reproducibility by a factor of approximately 2. In individual cases, the uncorrected and corrected values of mercury concentration can differ by as much as a factor of 6. Similar effects were observed in the correlation of the mercury concentration of a spot sample and the corresponding 24-hour excretion of mercury. For this set of data, the corrections for specific gravity and osmolality turned out to be almost identical. The correction for creatinine was more effective than the other corrections by a small but statistically significant amount.

Pulmonary function testing in the screening of workers: guidelines for instrumentation, performance, and interpretation.

Abstract: Medical surveillance of workers exposed to potential respiratory hazards may be a valuable tool in early recognition and prevention of certain occupational lung diseases. The use of pulmonary function tests, particularly spirometry, has been widely accepted as an integral part of respiratory surveillance. A National Aeronautics and Space Administration contract report on the Occupational Safety and Health Administration medical and workplace surveillance requirements and recommendations by the National Institute for Occupational Safety and Health is a recent detailed study of medical surveillance requirements and recommendations (unpublished study, 1983). This paper is a brief guide for those in the medical profession attempting to establish or improve their medical surveillance programs for occupational respiratory diseases. It describes procedures to use and techniques for interpreting test results, and finally includes a study of normal reference values. In addition, the references should provide additional information for establishing a respiratory medical surveillance program.

Sensitivity of fecal hemoccult testing and flexible sigmoidoscopy for colorectal cancer screening.

Abstract: Fecal Hemoccult testing and flexible sigmoidoscopy have been proposed as means of screening for colorectal cancer in the general population, as well as in identified high-risk groups. A colorectal cancer screening program was conducted for the Pattern Makers' League of North America. A total of 1,473 white males were screened with fecal Hemoccult testing and flexible sigmoidoscopy during the period 1981 to 1983. The fecal Hemoccult test after diet restriction was positive in 38 workers (2.6%). Among 12 colorectal cancers, including in situ cases, only three were positive by this test. The sensitivity of this test for picking up cancer is only 25%. The positive predictive value was 7.9%. It is concluded that the Hemoccult test for the detection of colorectal cancer and polyps is not a valuable tool because of low sensitivity, whereas flexible sigmoidoscopy has a significant role in colorectal cancer screening of an asymptomatic population at risk.

Occupational and sex differences in smoking and smoking cessation.

Abstract: Occupational and sex differences in the prevalence of smoking, smoking cessation, and attempts to quit smoking were studied cross-sectionally among employees of ten work sites (N = 3035). Comparisons by sex, occupation, and work site, controlling for age, were made using analysis of covariance. For both sexes, smoking prevalence was highest among blue collar workers and lowest among professionals. Successful cessation was most prevalent among professionals. At all occupational levels, smoking prevalence was higher in women than men. Although men were more likely to be exsmokers, no significant sex differences were found in the rate of recent cessation. Also, significant differences between work sites were found in the prevalences of smoking and overall cessation and in quit rates in the last two years. The high prevalence of smoking and the low interest in quitting among blue collar respondents indicate an important target for future work site interventions.

Occupational allergy to laboratory animals: an epidemiologic study.

Abstract: A cross-sectional study has been carried out at The National Institutes of Health to examine the prevalence of laboratory animal allergy (LAA) in a population exposed to animals, and to compare the prevalence of general allergy in the exposed v a control group. A group of 289 workers with light-to-moderate exposure to animals, 260 with heavy exposure, and 242 control subjects were interviewed. A slightly greater prevalence of general allergy was found among those working with laboratory animals (39%), than in the control group (33.9%), but the difference was not statistically significant. The prevalence of LAA in the total exposed group was 23.9%. A history of atopic problems and history of allergy to domestic animals correlated significantly with LAA, as did the number of species of animals handled and the average number of hours per week exposed to laboratory animals, with evidence of dose-response relationships.