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S Barnhart

Publications and source records attributed to S Barnhart.

54 records · Page 3Linked to original sources

Screening for occupational disease among workers in a high-risk trade: examination of cost, yield, and potential for increased efficiency.

We evaluated the cost and yield of a general health surveillance program emphasizing the identification of occupationally related diseases among workers in a high-risk trade. Of approximately 4,000 eligible members of two local plumbers and pipefitters unions, 639 were screened in this program. Screening tests indicated either by specific occupational exposures (eg, chest X-ray, spirometry, and audiometry) or general clinical risk factors (urine analysis for those with a positive urine dipstick, and stool heme occult testing for those over 45 years of age) proved to be far less costly for each positive finding than those procedures (physical examination, complete blood count, and blood chemistry panel) that were not specifically indicated. A discriminant analysis revealed predictor variables (age, years in the trade, and presence of respiratory symptoms) that, in subsequent screening efforts, could be used in the unscreened population either to identify individuals who are more likely to have any positive test result or to "tailor" the content of the initial screening program for a single individual. Increasing the yield and decreasing the direct costs of screening activities may make programs like these more affordable. In addition, this program assisted workers in filing for compensation and thus served to promote the appropriate transfer of cost for the identification and management of occupational diseases from traditional forms of payment to workers' compensation insurance programs.

Adolescent↗

The relation among pulmonary function, chest roentgenographic abnormalities, and smoking status in an asbestos-exposed cohort.

To clarify the clinical value of the International Labor Office (ILO) roentgenographic classification of pneumoconiosis in assessing asbestos-exposed persons, we determined the relationships among spirometric values, radiographic evidence of parenchymal pulmonary fibrosis and/or pleural thickening, and cigarette smoking history in 684 consecutively enrolled male plumbers and pipefitters participating in a larger cross-sectional prevalence study. The subjects were mainly marine pipefitters (35%), plumbers (24%), and steamfitters/welders (23%); 28% had never smoked, 39% were ex-smokers, and 33% currently smoked cigarettes. Mean values for FVC and FEV1 were 95.0 and 91.9% of predicted, respectively, with mean FEV1/FVC ratio 77.7%; by standard criteria, 7.8% had restrictive impairment, and 21.7%, obstructive defects. Chest radiographs were normal in 63% and showed pleural abnormalities only in 17%, parenchymal abnormalities only in 7%, and both pleural and parenchymal abnormalities in 12%. Both FVC and FEV1 correlated with the degree of small opacity profusion, as assessed by ILO grade. Pleural abnormalities were associated with lower FVC values, independently of ILO profusion grade for Grades less than or equal to 1/0, and were unexplained by smoking status. In addition, there was a positive association between smoking history and degree of ILO parenchymal abnormality, particularly in those with the heaviest cumulative smoking history. Our results suggest that the ILO classification of pneumoconiosis, although a useful epidemiologic tool, should be applied with caution in persons with asbestos exposure, and that pleural abnormalities may be associated with physiologic impairment in such persons.

Adult↗

Total lung capacity. An insensitive measure of impairment in patients with asbestosis and chronic obstructive pulmonary disease?

The total lung capacity (TLC) is frequently used as a measure of respiratory impairment in patients with asbestosis. Because asbestosis and chronic obstructive pulmonary disease (COPD) exert opposite effects on the TLC, it may be an insensitive measure of impairment in patients with both abnormalities. To assess this, we compared asbestos-exposed patients with functional evidence of COPD and radiographic evidence of interstitial fibrosis (group 1) to those with interstitial fibrosis alone (group 2). Despite the two groups being comparable in degree of radiographic "fibrosis," no case of restrictive impairment (reduced TLC) was identified among those with both interstitial fibrosis and COPD (group 1), compared to 33 percent of those with interstitial fibrosis alone (group 2). In addition, those patients with both interstitial fibrosis and COPD, compared to those with interstitial fibrosis alone, were found to have greater impairment as measured by alveolar-arterial oxygen difference and diffusing capacity. We conclude that the TLC is an insensitive measure of impairment due to asbestosis in patients with the common setting of coexistent asbestosis and COPD.

Aged↗

Use of oblique chest roentgenograms in detecting pleural disease in asbestos-exposed workers.

Oblique chest roentgenograms have been recommended by some for use in screening programs of asbestos-exposed workers to increase detection of pleural fibrosis not evident on posteroanterior (PA) films. As a screening test, identification of pleural abnormalities with oblique films is especially important in subjects without evidence of other asbestos-induced abnormalities on PA films, namely, parenchymal fibrosis. To evaluate the incremental value of oblique films in the identification of pleural fibrosis, a comparison was made between PA films read alone and PA films read with both oblique views in a systematic evaluation of 489 male pipefitters examined in a screening program. Analysis of the subsets of pipefitters with and without parenchymal fibrosis showed that 2.5% of workers with normal PA films (n = 326) and 13.0% of subjects with isolated parenchymal fibrosis on PA films (n = 46) had pleural fibrosis detectable only on oblique films. In only eight (1.6%) did the oblique view represent the sole evidence of an asbestos-related roentgenographic abnormality. We conclude that oblique films should not be routinely used in screening workers for evidence of asbestos-induced disease.

Adult↗

Carpal tunnel syndrome in grocery checkers. A cluster of a work-related illness.

Grocery checkers must use a high level of repetitive motion in the course of their work. We report a cluster of seven cases of the carpal tunnel syndrome felt to be due to the excessive use of repetitive motion. Each of the grocery checkers had no other identifiable risk factors, and hand pain, physical examination abnormalities and prolonged median nerve sensory latencies had developed that were consistent with the diagnosis of the carpal tunnel syndrome. This cluster of cases, the relation of the history of their disorder to time at work and a review of the literature suggest that grocery checkers, because of their excessively repetitive tasks, are at increased risk for the carpal tunnel syndrome.

Adult↗

Cadmium chemical pneumonitis.

Metal fume exposures are common to a number of trades and may result in the self-limited acute toxic syndrome of metal fume fever. Acute inhalational cadmium toxicity may mimic metal fume fever on initial presentation, but may have a markedly different clinical course. We report a case of cadmium-induced chemical pneumonitis in a welder who, over four years, has shown persistent pulmonary function abnormalities. The potential for acute cadmium toxicity needs to be considered in any patient suspected of having metal fume fever.

Adult↗

An evaluation of factors affecting hazardous waste workers' use of respiratory protective equipment.

The purpose of this study was to describe the perceptions of a group of hazardous waste workers about their workplace hazards and to understand their beliefs and attitudes about the use of respiratory protective equipment (RPE). There were two phases of data collection: (1) interviews to identify factors that influence respirator use and (2) a written survey to evaluate the importance of these factors. This article describes the findings from the written survey completed by 255 eligible respondents (return rate = 46.5%, 255/548). Subjects used a weighting system to score 18 identified factors that influence the use of RPE. Scores were compared according to type of respirator, frequency of use, and associated health symptoms. The factors that had the most positive influence on respirator use were concern about work exposure, fit-testing, and training. The most negative influences were communication, personal comfort, effect on vision, structural environment, and fatigue. More frequent users (once per month or more) were significantly more likely to view fit-testing, health effects, and effects on vision negatively than were less frequent users. Persons who reported health symptoms associated with respirator use had more negative scores than persons without health symptoms. Workers categorized as laborers were more likely to be frequent respirator users and to wear supplied-air respirators, and were significantly more likely to view vulnerability to disease negatively, than were other worker groups. The findings from this study indicate that respiratory protection programs must extend beyond training and education; to be maximally effective, health professionals must be responsive to the specific concerns of the workers.

Adult↗

Barriers and solutions in implementing occupational health and safety services at a large nuclear weapons facility.

The Hanford Nuclear Reservation is one of the U.S. Department of Energy's largest nuclear weapons sites. The enormous changes experienced by Hanford over the last several years, as its mission has shifted from weapons production to cleanup, has profoundly affected its occupational health and safety services. Innovative programs and new initiatives hold promise for a safer workplace for the thousands of workers at Hanford and other DOE sites. However, occupational health and safety professionals continue to face multiple organizational, economic, and cultural challenges. A major problem identified during this review was the lack of coordination of onsite services. Because each health and safety program operates independently (albeit with the guidance of the Richland field operations office), many services are duplicative and the health and safety system is fragmented. The fragmentation is compounded by the lack of centralized data repositories for demographic and exposure data. Innovative measures such as a questionnaire-driven Employee Job Task Analysis linked to medical examinations has allowed the site to move from the inefficient and potentially dangerous administrative medical monitoring assignment to defensible risk-based assignments and could serve as a framework for improving centralized data management and service delivery.

Contract Services↗

An occupational risk survey of a refractory brick company in Ha Noi, Viet Nam.

Viet Nam has an increasing need for building materials, including refractory bricks. Little is known regarding the occupational hazards incurred in brick manufacturing. To determine the occupational health hazards posed by a refractory brick operation in Ha Noi, Viet Nam, a cross-sectional occupational risk survey was conducted, focusing on respirable dust hazards. It included an industrial hygiene walk-through and gravimetric dust analysis. Noise, heat, lack of head protection, and dust exposure were hazards identified at the brick-manufacturing site. Respiratory protection involved a three-layer cloth mask that had not been tested for efficacy. Silica dust exposure levels exceeded the Vietnamese permissible exposure level by almost fivefold based on gravimetric assessment and estimated silica content. This brick manufacturing site contains significant injury and respiratory illness hazards. Further investigations are necessary to begin to develop occupational safety measures at the site.

Accidents, Occupational↗

Pediatric environmental health: perceptions from a survey questionnaire.

To expand the base of knowledge regarding perceptions about potential environmental threats to children's health, a survey was conducted in the Northwest United States. Samples of Head Start parents, PTA presidents, public health officials, school nurses, naturopathic physicians, family practitioners, and pediatricians were mailed a questionnaire inquiring into the nature and degree of concerns about pediatric environmental health. The response rate was 24%. Trends in the data showed disparities in perceptions regarding levels of concern and exposure concerns between respondent categories. Disparities also existed regarding information resources used for children's environmental health. Recognizing differences in perceptions of children's environmental health, as demonstrated in these results, may be useful for risk communication and resource allocation, especially in the context of the wide variety of health belief models. Such knowledge may help clarity situations with environmental health risk concerns, including clinical, public health, and educational circumstances.

Adult↗

The structure and function of the occupational health system in Thailand.

This article describes the challenges facing the Thai occupational health system as a result of the enormous growth in the manufacturing sector. It contains a brief history of recent developments in the occupational health system, including the redistribution of responsibilities among government ministries and the enactment of new occupational health regulations.

Developing Countries↗

Hyperventilation following a large-scale hazardous-materials incident.

Actual or perceived exposure to hazardous materials may result in physiologic and psychological effects. However, hyperventilation following such exposures has not previously been reported. After a large-scale industrial release of oxides of nitrogen, five (29%) of 17 patients evaluated at a major trauma center were hyperventilating, as defined by arterial PCO2 <33 mm Hg, and nine patients (53%) had arterial PCO2 <37 mm Hg. First responders (rescue team members and paramedics) had a higher rate of hyperventilation than other occupational groups. Age, gender, marital status, decontamination, and mode of arrival were not significantly associated with hyperventilation, although marital status approached significance. This study suggests that hyperventilation may be a common reaction after hazardous-materials incidents, and that certain populations may be at increased risk for this condition.

Adolescent↗

The respiratory effects of volatile organic compounds.

Volatile organic compounds (VOCs) have been implicated as causative agents in asthma and building-related illness. To determine whether a mixture of VOCs could impair lung function or cause airway inflammation among subjects without bronchial hyperresponsiveness, the authors conducted a randomized, crossover-design trial of controlled human exposures to filtered air for four hours, VOCs at 25 mg/m(3) for four hours, and VOCs at 50 mg/m(3) for four hours, using a VOC mixture based on sampling of indoor environments. VOC exposures caused dose-related increases in lower respiratory, upper respiratory, and non-respiratory symptoms, with no significant change in lung function (FEV(1);, FVC, or FEF(25-75), nasal lavage cellularity or differential cell counts, induced sputum cellularity or differential cell counts, or biomarkers of airway inflammation, including IL-8, LTB(4), or albumin in nasal lavage or induced sputum samples. Atopic individuals had significantly reduced FEE(25-75 following exposure to VOCs at 50 mg/m(3), suggesting that these individuals may be more sensitive to the health effects of VOCs. The authors conclude that reductions in levels of VOCs to substantially less than 25 mg/m(3) are required if a "non-irritating" work environment is desired.

Adult↗

Clinical experiences: development of a medical surveillance protocol for hazardous waste workers.

Medical surveillance of hazardous waste workers is essential for the health of these workers, who have unique, complex exposures. In order for this preventive tool to be effective, the supervising and/or examining physician must be educated about the specific health risks of hazardous waste workers and also must perform a comprehensive examination. Results of testing should be evaluated both for remarkable abnormalities as well as longitudinal subtle changes in individuals, and also for trends in workers with similar exposures. Fitness for duty determinations should be then made with appropriate communication of abnormalities and follow-up recommendations to both employers and employees. To date, clinical and research findings from clinical centers performing surveillance examinations on hazardous waste workers have not revealed remarkable abnormalities related to their potential exposures. The possible causes for these results include: (1) the workers have been well protected; (2) the current diagnostic methodologies are not sensitive enough to detect pathophysiologic changes; and (3) disease may not yet be manifest due to latency or cumulative effects of long-term low-dose exposure. In addition, one must keep in mind that previous clinical and research data were collected from test results of workers who were mainly involved in feasibility, as opposed to remediation, activities. With the prospective change of more clean-up involvement of hazardous waste workers, their potential for exposure may increase. Therefore, periodic collaborative evaluation of existing surveillance programs' results (e.g., every 5 years) is advised. This would allow determination of the efficacy of the current diagnostic methods in detecting disease, as well as the possible inclusion of more sensitive and/or specific newer technologies for use on a more routine basis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Evaluation of impairment and disability in occupational lung disease.

At least 260,000 workers suffer from work-related respiratory diseases in the United States. For physicians who wish to determine whether a respiratory disease is caused or aggravated by a patient's occupation, the diagnosis is followed by questions of attribution, impairment and disability, which are addressed in this article.

Disability Evaluation↗

The Carotene and Retinol Efficacy Trial (CARET) to prevent lung cancer in high-risk populations: pilot study with asbestos-exposed workers.

Pilot studies are an essential component for major chemoprevention trials. Prior to initiating the multicenter Carotene and Retinol Efficacy Trial to assess the effectiveness of beta-carotene and retinol for preventing lung cancer, we conducted pilot studies in Seattle between 1985 and 1988 in two high risk populations: current and former heavy smokers and asbestos-exposed workers. The Asbestos Workers Pilot Study for the Carotene and Retinol Efficacy Trial demonstrated that recruitment of asbestos-exposed participants with relevant risk factors was feasible from identified sources. We documented negligible toxicity and high adherence with the protocol, schedule, and intervention. Results from the pilot led to extension of the placebo run-in period, changes in the eligibility criteria, improvements in recruitment strategies and scheduling, elimination of stratification by risk factors in randomization, modifications of study vitamin dosage and of side effects monitoring, and refinement of trial design parameters for Carotene and Retinol Efficacy Trial. The Smokers Pilot is reported in the accompanying article (G. E. Goodman et al., Cancer Epidemiol., Biomarkers & Prev., 2: 389-396, 1993).

Aged↗