摘要:

AbstractA discussion of the history of substitutions in industrial solvent use is presented, and animal carcinogenicity studies with certain chlorinated hydrocarbon solvents are reviewed. The present knowledge on the association between occupational exposure to chlorinated hydrocarbon solvents and human carcinogenicity is summarized, including a critical review of 23 studies pertaining to human carcinogenicity. Several deficiencies are identified in these studies that make interpretation of the results uncertain, including poor characterization of exposures in qualitative and quantitative terms, the small numbers of deaths or cases, and short follow‐up periods. Despite these weaknesses, we conclude that, when viewed collectively, the evidence strongly suggests that occupational exposures to chlorinated hydrocarbon solvents are associated with an excess human cancer risk. The literature supports an association between occupational exposures to chlorinated hydrocarbons and elevated risks of leukemia, lymphoma, and urinary tract cancer. Parental occupational exposures are consistently associated with an elevated childhood cancer risk in the offspring. © 1993 Wiley‐Liss,

ISSN:0271-3586    

DOI:10.1002/ajim.4700240402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractInhalation of dust from contaminated organic materials may result in acute respiratory tract illness. Possible mechanisms include toxic and cellular reactions to microbial and other organic products or immunologic responses after prior sensitization to an antigen. A case is presented of a 52 year old male who developed fever, myalgia, and marked dyspnea 12 hr after shoveling composted wood chips and leaves. Inspiratory crackles, hypoxemia, and bilateral patchy pulmonary infiltrates were seen. Precipitating antibody tests for the usual antigens were inconclusive. He improved over 3 days.In order to assess the environmental conditions the patient had experienced, we returned to the site to reproduce and measure respiratory exposures during hand loading of the compost. Visible clouds of fine particulate were easily generated during handling activities. Microscopic examination of these dusts indicated a predominance of spores. Endotoxin concentrations from inspirable and respirable dust samples ranged from 636 to 16,300 endotoxin units/m3. Levels of contaminants found were consistent with those associated with respiratory illness in other agricultural settings.Two respiratory disorders, hypersensitivity pneumonitis (HP) and organic dust toxic syndrome (ODTS), may occur after exposure to organic dusts containing fungal spores and endotoxins. Despite extensive clinical and environmental investigations, we were unable to differentiate these two disorders, and suggest they may represent parts of a spectrum of responses to complex organic dusts, rather than completely distinct clinical entities. © 1993 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of Ameri

ISSN:0271-3586    

DOI:10.1002/ajim.4700240403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThe objective of this investigation was to elucidate the pulmonary responses of an animal model to dust generated from leaf/wood compost which had caused a severe case of acute respiratory illness in an individual. Guinea pigs were exposed for 4 hr to 30 mg/m3of aerosolized leaf/wood compost dust. Inhalation resulted in significant cellular activation and changes in pulmonary mechanics. Maximal elevation in breathing rate (↑ 36%) was observed 12–18 hr postexposure. Similarly, maximal granulocyte infiltration (↑ 1,600%) and activation of alveolar macrophages (↑ 65%) occurred 18 hr postexposure. In contrast, maximal airway obstruction (↑ 65%) occurred 18 hr postexposure. In contrast, maximal airway obstruction (↑ 120%) occurred immediately after exposure and returned toward normal (↑ 53%) by 18 hr postexposure. In several respects, the airway obstruction and pulmonary inflammation described in the animal model were comparable to the human response to compost dust. Therefore, this animal model may be useful in predicting the potential respiratory hazard associated with exposure to various organic dusts. © 1993 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United S

ISSN:0271-3586    

DOI:10.1002/ajim.4700240404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractA respiratory health survey was conducted in a grain mill and the relationship of health indicators to quantitative measures of airborne dust, fungal, and bacterial contamination was examined. Respiratory symptoms were more prevalent in the high dust exposure categories; lung function levels were also higher in the high dust exposure categories, consistent with a “healthy” worker effect. Workers in the three higher dust exposure categories showed either no change or a decrease in lung function over the working week, while workers in the low exposure category demonstrated an improvement in lung function over the working week. Total dust and microbiological (fungal and bacterial) load were found to be significantly related to each other, and the relationship of microbiological load to lung function level and changes over the working week were similar to those found for total dust © 1993 Wiley‐Lis

ISSN:0271-3586    

DOI:10.1002/ajim.4700240405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractObjective measures of exposure furnished by dust monitoring are both costly and time consuming and require a sufficient level of technology. However, they are important in demonstrating exposure‐response relationships, in furnishing information necessary to establish environmental control levels, and to assess if interventions, for instance, improving dust control, have been effective. In this paper respiratory symptoms and cross‐shift changes in spirometric lung function were related to dust exposure level in a grain mill assessed in two ways, subjectively (by workers themselves on a four point scale) and objectively (by personal dust monitoring). Health indicators that depend on the individual's perception (e.g., symptoms) correlated more closely with the subjectively assessed dust category, while health indicators that were measured objectively (e.g., cross‐week FVC and FEV1change) correlated more closely with the objectively assessed dust category. However, the patterns of relationship of respiratory health indicators to either dust category were similar, and exposure assessed by one method was, to a large extent, a proxy for the other. The most significant predictor of workers' choice of dust exposure category was the measured dust level. These findings indicate that exposure categories based on workers' assessment of dustiness can be a useful tool in etiologic research, in particular in establishing exposure‐response relationships. © 1993 Wiley

ISSN:0271-3586    

DOI:10.1002/ajim.4700240406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractConstruction laborers have some of the highest death rates of any occupation in the United States. There has been very little systematic research focused exclusively on “laborers” as opposed to other workers in the construction industry. We reviewed the English language literature and various data bases describing the occupational tasks, exposures, and work‐related health risks of construction laborers. The sources of information included 1) occupational mortality surveillance data collected by the states of California and Washington and the National Institute for Occupational Safety and Health (NIOSH); 2) National Occupational Exposure Survey; 3) national fatality data; 4) cancer registry data; and 5) case reports of specific causes of morbidity. While the literature reported that construction laborers have increased risk for mesothelioma, on‐the‐job trauma, acute lead poisoning, musculoskeletal injury, and dermatitis, the work relatedness of excess risks for all‐cause mortality, cirrhosis, cerebrovascular disease, chronic obstructive pulmonary disease, ischemic heart disease, and leukemia is less clear. Furthermore, while laborers are known to be potentially exposed to asbestos, noise, and lead, and the NIOSH Job Exposure Matrix describes other potential hazardous exposures, little research has characterized other possible exposures and no research has been found that describes the exposures associated with specific job tasks. More advanced study designs are needed that include a better understanding of the job tasks and exposures to construction laborers, in order to evaluate specific exposure‐disease relationships and to develop intervention programs aimed at reducing the rate of work‐related diseases. © 1993 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United

ISSN:0271-3586    

DOI:10.1002/ajim.4700240407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThe radiological findings for the profusion of rounded opacities were compared to pathological findings for parenchymal silicosis in 557 gold miners who had, on average, 2.7 years between the radiological and pathological examination. Three readers read the radiographs, and ILO category 1/1 or more was defined as a positive diagnosis of silicosis. The sensitivity values were 0.393, 0.371, and 0.236, and the specificity values were 0.987, 0.965, and 0.978, for the three readers, respectively. The sensitivity of the readers improved with increasing degree of autopsy silicosis, but a large proportion of those with a moderate and marked degree of silicosis were not diagnosed radiologically. The diagnostic sensitivity of the radiological test could be improved by using category 0/1 as a cutoff point for workers exposed to a high average concentration of respirable silica dust. The diagnostic specificity of radiology could be improved by using category 1/0 or 1/1 as a cutoff point for a positive diagnosis for workers exposed to a low average concentration of respirable silica dust. © 1993 Wiley‐Liss, I

ISSN:0271-3586    

DOI:10.1002/ajim.4700240408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThe risk of silicosis was investigated in a cohort of 2,235 white South African gold miners who had, on average, 24 years of net service from 1940 to the early 1970s and who were followed up to 1991 for radiological signs of onset of silicosis (ILO category 1/1 or more). There were 313 (14%) miners who developed signs of silicosis at an average age of 55.9 years. The latency period was largely independent of the cumulative dust exposure. In 57% of the silicotics, the radiological signs developed, on average, 7.4 years after mining exposure ceased. The risk of silicosis increased exponentially with the cumulative dust dose, the accelerated increase being after 7 mg/m3‐years. At the highest exposure level of 15 mg/m3‐years, which represents approximately 37 years of gold mining at an average respirable dust concentration of 0.4 mg/m3, the cumulative risk for silicosis reached 77%. In conclusion, the risk of silicosis was strongly dose dependent; however, the latency period was largely independent of the dose. © 1993 Wiley‐Lis

ISSN:0271-3586    

DOI:10.1002/ajim.4700240409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractIn a 5‐year follow‐up study of 88 animal exposed laboratory technicians, the incidence of laboratory animal allergy (LAA), lung function, and the development of allergy test reactivity were investigated. Only two individuals developed test positive LAA rhinitis during the follow‐up period. Furthermore, one subject who had previously had LAA rhinitis developed LAA asthma. In the remaining subjects the results of skin prick tests against laboratory animals and environmental allergens, total serum IgE levels, and lung function were unchanged. Atopy defined as parental and childhood allergy, raised total serum IgE levels, and positive skin prick tests against nonanimal environmental allergens and nonlaboratory animals (dog and horse) were risk indicators for development of test positive LAA asthma. The low incidence of LAA during the 5‐year follow‐up is interpreted as a result of an early LAA development in atopic subjects. © 1993 Wiley

ISSN:0271-3586    

DOI:10.1002/ajim.4700240410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThis retrospective follow‐up study evaluates the mortality experience of 123,232 male hourly workers employed at a motor vehicle manufacturing company in 1973. Company computerized personnel records were used to identify subjects and to obtain their employment history. Follow‐up through December 31, 1985 was conducted using company, state, and national data sources. The mortality rates of the cohort were compared with the rates of the United States (U.S.) general population of white or black men, adjusting for age and calendar time, and using the standardized mortality ratio (SMR) as the measure of association.The overall mortality rate of cohort members is lower than the U.S. rate by 11% among whites (11,060 observed/12,427 expected deaths; SMR = 89) and by 24% among blacks (3,744/4,926 deaths; SMR = 76). These low mortality rates reflect deficits of diseases other than cancer. Cancer SMRs are 99 for whites and 90 for blacks. There are slight excesses of stomach cancer (SMR = 113) and of lung cancer (SMR = 108) among whites and of cancer of the large intestine and rectum (SMR = 114) and of the lymphopoietic tissue (SMR = 111) among blacks. Both whites and blacks have a large deficit of buccal cancer and pharynx cancer, and blacks also have a deficit of esophagus cancer.The cohort's overall deficit of deaths is due largely to the favorable mortality experience of active workers. In contrast, white subjects who have left active employment have an 11% mortality excess, and inactive black subjects have a mortality rate that is similar to the general population rate. The increased mortality among inactive whites is not limited to any one particular disease category. This pattern may reflect illness‐related employment termination and generalized confounding by socioeconomic status, although the study does not rule out a relationship between workplace exposures and specific diseases. © 1993 Wiley‐L

ISSN:0271-3586    

DOI:10.1002/ajim.4700240411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY