Showing papers in "Journal of Occupational and Environmental Medicine in 1978"

A study of three preventive approaches to low back injury.

Abstract: The prevention of low back injuries in industry has traditionally been attempted by (1) careful selection of workers, (2) good training in safe lifting, and (3) designing the job to fit the worker (ergonomics). One hundred ninety-one low back injuries were analyzed to determine the effectiveness of each preventive approach. The results indicate that the common selection techniques, as they are being used today, are not an effective control for low back injuries. Similarly, training on safe lifting procedures, as it is being administered today, is not an effective control for low back injuries. It was determined that a worker is three times more susceptible to low back injury if exposed to excessive manual handling tasks. The ergonomic redesign of these tasks to reduce the manual handling exposure represents a partial control for low back injuries.

Psychological performance of subjects with low exposure to lead.

Abstract: In a study of the effects of low lead exposure on psychological performance, 49 exposed workers and 24 controls were given a psychological test battery. All the lead workers had been under regular monitoring during their entire exposure time, and only workers whose maximal blood lead concentration had never exceeded 70 microgram/100 ml were included in the study. At the time of the examination, the mean blood lead level of the exposed group was 32 +/- 11 microgram/100 ml. Comparisons were made both between exposed and nonexposed workers and within the exposed group. In the latter case, the maximal, the average and the actual blood lead concentrations were used as measures of uptake. The most important finding was a significant relationship between impaired psychological performance and lead uptake within the exposed group. The performances that were most affected by lead depended on visual intelligence and visual-motor functions. Age and neuroticism did not explain these relationships. The impairment of psychological performance correlated better with the average than with the maximal or actual blood lead concentration. Considering that no single blood lead concentration had ever exceeded 70 microgram/100 ml, these findings indicate that the threshold for impaired performance lies below that level.

Nitrogen dioxide-induced pulmonary disease: five new cases and a review of the leterature.

Abstract: Twenty-three patients exposed to nitrogen dioxide in agriculture or industry were referred to the University of Wisconsin Medical Center. Eighteen experienced a transient upper respiratory tract syndrome; five developed pulmonary edema or bronchiolitis obliterans. This latter group responded to steroid therapy but all demonstrated evidence of persistent pulmonary dysfunction on follow-up studies. Combining our findings with those in the literature we concluded: (1) exposure to NO2 is more common than generally appreciated; (2) case fatality is high--29% for silo-filler's disease; (3) steroids are effective therapy and should be continued for at least eight weeks; (4) although the majority recover without significant sequelae, some individuals may develop persistent functional abnormalities; (5) there is no evidence that long-term exposure to low concentrations of NO2 leads to chronic airway obstruction; and, (6) NO2-induced pulmonary disease could be elminated with appropriate preventive measures.

Chronic mercury poisoning from a single brief exposure.

Abstract: For a number of years we have observed six patients whose illness began after inhaling high concentrations of mercury vapor in a single exposure. They all had symptoms of acute mercury poisoning with fever, chills, chest pain, and weakness. Three men had diffuse pulmonary infiltrates on chest x-ray suggesting chemical pneumonitis. Two of the men excreted large amounts of mercury in their urine two days after exposure following BAL therapy. Their chronic symptoms differed somewhat, but many complained of nervousness, irritability, lack of ambition, and loss of sexual desire. Chronic mercury poisoning is generally felt to follow only long periods of exposure. Although thess patients had symptoms which are not pathognomonic of chronic mercury poisoning, we feel the events described strongly suggest their relationship to a single brief exposure and represent a form of chronic mercurialism.

A program of heart disease intervention for public employees. A five year report.

Abstract: The five-year experience involving over 800 employees has effected reduced coronary risk factors, improved physical work capacity and maximal oxygen uptake and reduced employee absenteeism from personal sick leave. As in all instances where the self-selection process confounds the nature of the results, the extent of extrapolation from these data must be guarded. Nevertheless, the results support and further extend previous studies suggesting a reduction of CVD following formal behavior and life-style modification. It is the opinion of the authors that similar programs can be implemented where health services, flexible hours, agency cooperation and salaried coordinators can be assembled.

Inorganic mercury intoxication reminiscent of amyotrophic lateral sclerosis.

Abstract: Two employees in a mercuric oxide manufacturing plant developed neurologic changes not previously reported from the exposure to inorganic mercury or elemental mercury vapor. The symptoms, physical findings and laboratory studies resembled those found in amyotrophic lateral sclerosis (ALS) and organic mercury intoxication. Nineteen employees are reported who precipitously developed signs and symptoms which may be regarded to be the early onset of a symptom complex of mercury intoxication that would likely have progressed to the ALS-like syndrome if the progression had not been interrupted by removal of the individuals from exposure to mercury. All symptoms, signs, and laboratory findings returned completely to normal after approximately three months in a mercury free work environment. Language: en

Stress levels of ambulance paramedics and fire fighters.

Abstract: Responses to Rahe and job stress questionnaires and urinary concentrations of cortisols and catecholamines served to indicate work related stress in 56 fire fighters and 67 paramedics. Although the average Rahe test scores, indicative of stress arising from life events, were comparable, those of the job stress test were statistically significantly higher for the paramedics. The paramedics felt their jobs more exhausting, less satisfying and requiring too much responsibility. For the paramedics, statistically significant higher levels of epinephrine and elevated levels of norepinephrine were found for the work as compared to the off day. For fire fighters, higher levels of cortisol and norepinephrine evident on the off day rather than the work day apparently reflect the relatively light work load experienced during the span of urine collections.

Transcutaneous ethylene glycol monomethyl ether poisoning in the work setting.

Abstract: During the period of an "energy crisis" in 1974, two workers in a textile printing plant in Massachusetts developed clinical manifestations of encephalopathy. Both had evidence of bone marrow injury and one had pancytopenia. Study of their work environment revealed that they had ethylene glycol monomethyl either (EGMME) poisoning primarily due to cutaneous exposure. EGMME was used as a cleansing agent as a substitute for acetone, which was unavailable due to temporary shortage. Proper product labels could have prevented the illness.

Clinical and immunological findings in workers exposed to sewage dust.

Abstract: A clinical investigation was made between workers exposed to dried sewage sludge dust and age matched controls not exposed. About 50% of the workers reported work related fever, eye symptoms and general fatigue. Thirteen percent of the workers in the sewage plant reported work related diarrhea. Serum immunoglobulins, white blood cells and thrombocytes were elevated and a higher percentage of increased levels of C-reactive protein and fibrinogen degradation products was found in the exposed group. Although no definite cause-effect relationship could be established, it is suggested that the responsible agent in the environment is endotoxins.

Occupational exposures to cyanide in Baltimore fire fighters.

Abstract: A group of 479 fire fighters were investigated for routine exposure to hydrogen cyanide in the fire atmosphere using measurements of serum thiocyanate (SCN-). Our findings indicate that fire fighters were exposed to levels of hydrogen cyanide sufficient to raise their mean serum thiocyanate (SCN-) levels above that of controls. This elevation of serum SCN- occurred independently of smoking habits. Exposure to cyanide occurred much less frequently than previously studied exposures to carbon monoxide. Difficulties of correlating acute symptoms and the effectiveness of mask use with serum thiocyanate are discussed. Language: en

The influence of two barrier creams on the percutaneous absorption of m-xylene in man.

Abstract: Human volunteers were exposed to m-xylene by the percutaneous route (both hands immersed into the solvent for 20 minutes). The total amount of unchanged m-xylene eliminated through the respiratory tract during and after exposure and the total quantity of m-methylhippuric acid eliminated in urine during the subsequent 24 hours were measured. The majority of absorbed m-xylene (86 to 98%) is eliminated as m-methylhippuric acid in urine. The results obtained on eight subjects who repeated the test twice indicate that under similar experimental conditions the quantity of m-xylene absorbed percutaneously by an individual may vary with time by a factor of 2 or less. The interindividual variability in the total amount of m-xylene absorbed through the skin is greater than the intraindividual variability. Among 13 subjects, the ratio between the highest and the lowest value is 6.2; the mean percutaneous absorption rate of m-xylene amounts to 2.45 microgram/cm2 x min. The application of a barrier cream containing 10% silicone did not significantly influence the rate of percutaneous absorpiton of m-xylene by 11 subjects. Preliminary results obtained of five volunteers suggest that the application of a cream containing glycerol, stearates and oleostearates was not more effective.

Physiological effects of rotational work shifting: a review.

Abstract: The high cost of capital equipment, demands of the world markets, and continuity requirements of many technological processes have forced industry to operate three-shift, 24-hour days. Workers on fixed schedules experience no particular problems from shift work, but those who are shifted periodically can undergo physiological and emotional disturbances. These disturbances occur because most human systems function according to circadian rhythms that can be easily disoriented. The primary cause is the periodic shifting of the light-dark, wake-sleep cycles. Extensive literature exists on the cause and symptoms of disturbances in the human physiological rhythms. The information contained in this literature can be applied to protecting the health and well-being of the worker. Language: en

A respiratory survey of cedar mill workers. I. Prevalence of symptoms and pulmonary function abnormalities.

Abstract: A respiratory-occupational questionnaire and spirometry were used to compare the prevalence of symptoms and pulmonary function abnormalities in 405 workers exposed to red cedar dust and 252 control workers exposed to other wood dusts. Compared with controls, the cedar workers were found to have a significantly higher prevalence of respiratory symptoms, cough, phlegm, wheeze and breathlessness, as well as more rhinitis and conjunctivitis. While, as expected, there was a clear relationship between respiratory symptoms and cigarette smoking, there was also evidence to suggest a synergistic effect between exposure to cedar dust and smoking. There was no difference in the lung function between cedar workers and controls. Sixty-five workers in the control group previously had worked in red cedar mills; they had a higher prevalence of respiratory symptoms than other workers in this group. Red cedar asthma was found in only 1.1% of the cedar workers. This condition usually develops in the early months of exposure, and workers who are affected tend to leave the industry. The probable incidence of red cedar asthma was estimated to be higher, around 4-5%.

Mortality in unionized truck drivers.

Abstract: To determine occupational mortality in the Central States Teamster population, all death certificates for a three-month period in 1976 were collected and coded. With the exception of respiratory tract cancer and motor vehicle accident deaths, mortality rates were lower than those found in the U.S. population and comparable to those found in other employed populations. It was not possible to separate the effect of cigarette smoking from environmental exposure to explain the excess respiratory tract cancer death. Unexpectedly, the majority of accident mortalities occurred away from work rather than at work. Language: en

Effects of chronic occupational exposure to measured concentrations of benzene

Abstract: All ten employees have a history of exposure to benzene which exceeded a 25 ppm, eight-hour TWA for several years. For five of these employees this exposure level started over 20 years ago. One employee's high exposure level started over 35 years ago. All ten employees had their initial high exposure to benzene more than 16 years ago. At one period (late 1963 and early 1964) all ten employees had alterations in their peripheral blood studies, evidenced by an increase in MCV. Some of the employees had slight reduction of hemoglobin levels. No other significant blood or bone marrow abnormalities were evident. A mortality study, for the years 1940 to 1973, of 594 employees chronically exposed to benzene at the Midland, Mich., Dow location has recently been accepted for publication. This study was followed by a morbidity study of 282 employees, which were a subset of the employees in the mortality study. The morbidity study was based on health data obtained between 1967 and 1974. The ten employees described in this article were included in both the mortality study population of 594 employees and the morbidity study of the 282 employees.

Differences in pulmonary function tests among whites, blacks, and American Indians in a textile company.

Abstract: Normal standards for pulmonary function in nonwhite populations are not presently available to occupational health workers. The present study examined differences in %FVC, FVC, FEV1/FVC, FEF 200-1200 and FEF 25-75% among whites, blacks, and American Indians. The sample consisted of 4209 job applicants to a textile company in southeastern United States. Multiple regression and analyses of covariance were employed to control differences in age, height, weight, and smoking status. Blacks were significantly lower in five of the six comparisons but higher in FEV1/FVC%. The pulmonary function measures of Indians fell generally between those of whites and blacks. Differences were observed between blacks and whites of both sexes regarding the effects of cigarette smoking. The need for race specific stardards was confirmed and the question of using smokers in the acquisition of normative data was raised.

Mortality of female workers in rubber manufacturing plant.

Abstract: The ten-year mortality experience of a cohort of white female production workers in a large rubber manufacturing plant is presented. An analysis of the observed and expected numbers of death from numerous causes revealed a slightly elevated overall standarized mortality ratio with an excess of deaths from both lung cancer and myocardial infarction, and a deficit of deaths from breast cancer. About two-thirds of all women in this cohort had worked, for the longest period of employment, in the manufacture of industrial products, while the remainder were engaged mostly in the manufacture of tires. Some preliminary associations between type of job and mortality experience are discussed, but a more detailed analytic investigation is required before nonoccupational risk factors can be ruled out.

Monomethylformamide levels in human urine after repetitive exposure to dimethylformamide vapor.

Abstract: Eight healthy male subjects were exposed to DMF vapor at a concentration of 879 +/- 033 ppm for six hours daily for five consecutive days All urine voided by the subjects was collected from the beginning of the first exposure to 24 hours past the end of the last exposure and each sample was analyzed for monomethylformamide (MMF) MMF was rapidly eliminated from the body with urine values peaking within a few hours following the end of each exposure period Very little was found in the 24-hour postexposure sample and none was found in a 48-hour postexposure sample There was no increased excretion of MMF in the urine following repetitive exposure The mean for the seven-hour (end of exposure) sample was 474 microgram/ml or 7368 microgram Lower and upper one-sided 95% tolerance limits for 95% of the population were 12 microgram/ml (367 microgram) and 139 microgram/ml (1625 microgram) The coefficient of variation (CV) for microgram MMF/ml was approximately 25 times more variable than the CV for total microgram

Analysis of physical fitness and coronary heart disease risk of Dallas area police officers.

Abstract: Two hundred thirteen male police officers between 21 and 52 years of age volunteered to participate in a physical evaluation and conditioning program. Information concerning the physical fitness status and risk of coronary heart disease (CHD) of police officers were shown. Younger police officers (less than 30 years of age) were average in physical fitness levels and CHD risk compared to the population of the same age. Middle-aged police officers were shown to be lower in physical fitness levels and higher in CHD risk compared to their cohorts. The results from this investigation support the need for physical fitness and preventive medicine programs for police officers.

Occupational asthma due to tetrachlorophthalic anhydride.

Abstract: The plastics industry utilizes a number of organic chemicals which have the potential of producing pulmonary reactions, particularly in susceptible individuals. Five workers are reported who were involved in the production of epoxy resins and developed recurrent respiratory symptoms and physiologic abnormalities following exposure to tetrachlorophthalic anhydride (TCPA). Inhalation challenge with TCPA reproduced their symptoms and demonstrated both an immediate and late (4-6 hours) physiologic response. Although the clinical picture strongly suggested a hypersensitivity reaction, immunologic studies failed to demonstrate precipitating or specific IgE antibody. Avoidance of exposure resulted in resolution of symptoms; however, three of the five individuals had residual functional impairment.

Epidemiologic investigation of employees chronically exposed to methylene chloride. Mortality analysis.

Abstract: A large male employee population with continuous low level work exposures to methylene chloride for up to 30 years was examined for mortality experience using non-concurrent prospective and proportionate mortality techniques. Mortality of the study group was consistent with industrial controls and less than the New York State general population. Life table analysis of the 1964 methylene chloride exposed cohort was followed through 1976 and demonstrated age group specific probabilities or 13 year survivorship equal to or better than that of three control male populations: Kodak Park, New York State, and United States.

Increased lead absorption in children of workers in a lead storage battery plant.

Abstract: Exposure to toxic materials originating in the workplace has been recognized in families of workers in several industries. However, to date this problem has not been studied in the storage battery production industry. Twenty-seven one- to six-year-old children of 22 workers at a storage battery plant at high risk of exposure to lead oxide were compared with 32 one- to six-year-old children in 22 neighborhood control families for evidence of increased lead absorption. Workers' children had significantly higher blood lead (p less than 0.001) and erythrocyte protoporphyrin (p less than 0.003) values than control children. Household exposures to lead in paint and water were similar for the two groups, but workers' homes had significantly higher concentrations of lead in dust (p less than 0.001). It is postulated that lead is brought home on the skin, hair and clothing of the workers and that their children are ingesting or inhaling the lead in household dust. This is the first report of increased lead absorption in children of workers in this industry.

Health exam findings among individuals occupationally exposed to benzene.

Abstract: We previously conducted a cohort mortality study of 594 individuals occupationally exposed to measured concentrations of benzene. This report presents health examination findings for a subset of 282 men from the larger group. Although slight decreases in mean total bilirubin and RBC values were detected statistically in comparing the exposed group to controls, these changes were not regarded as clinically significant. No correlations were found between peripheral blood counts and latency, duration or intensity of benzene exposure. Presently we have no indication from our data of adverse effects of benzene having occurred in our subset. Variations in latency among individuals and the possibility of subtle changes effecting an eventual pattern contribute to the need for continued surveillance.