摘要:

AbstractEpidemiologic studies of occupational cohorts have played a major role in the quantitative assessment of risks associated with several carcinogenic hazards and are likely to play an increasingly important role in this area. Relatively little attention has been given in either the epidemiologic or the risk assessment literature to the development of appropriate methods for modeling epidemiologic data for quantitative risk assessment (QRA). The purpose of this paper is to review currently available methods for modeling epidemiologic data for risk assessment. The focus of this paper is on methods for use with retrospective cohort mortality studies of occupational groups for estimating cancer risk, since these are the data most commonly used when epidemiologic information is used for QRA. Both empirical (e.g., Poisson regression and Cox proportionate hazards model) and biologic (e.g., two‐stage models) models are considered. Analyses of a study of lung cancer among workers exposed to cadmium are used to illustrate these modeling methods. Based on this example it is demonstrated that the selection of a particular model may have a large influence on the resulting estimates of ris

ISSN:0271-3586    

DOI:10.1002/ajim.4700270202

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

年代:1995

数据来源: WILEY

摘要:

AbstractThe variability of exposure has important implications for the design of occupational epidemiologic studies. To assess the influence of this variability in the rubber industry, the efficiency of different schemes for classification of exposure to particulates, cyclohexane‐soluble contaminants, and solvents was assessed. Groupings based on job title, plant, factors affecting exposure, published classifications, and the International Standard Classification of Occupations of the International Labor Organization (ISCO‐ILO) were compared. Statistical parameters for contrast in average exposure between groups and precision of average exposure within groups were developed to enable comparison of the efficiency of different classification schemes.Grouping of exposure to particulates and dermal exposure appeared to be less efficient than grouping of exposure to solvents. Grouping of solvent exposure using occupational title groups, existing classification schemes, and schemes based on factors affecting exposure showed comparable high resolution in exposure levels. Even the most detailed grouping schemes based on the combination of plant and occupational title group showed relatively modest resolution in particulate and dermal exposure levels. Groupings based on factors affecting exposure showed similar resolution for these exposures, but had higher precision due to having fewer groups.Application of optimal exposure grouping strategies will benefit new research on cancer among rubber workers. Eventually, this might resolve the situation in which a complete industry was included on the list of proven human carcinog

ISSN:0271-3586    

DOI:10.1002/ajim.4700270203

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

年代:1995

数据来源: WILEY

摘要:

AbstractThe cancer incidence was investigated among 27,884 fishermen and sailors from the merchant fleet who had been members of a pension fund for seamen during 1958‐1986 in Iceland. The cancer incidence was followed through 1966‐1988. Expected values were based on rates for the general male population in Iceland. In the whole cohort, 758 malignant neoplasms had occurred as compared to 688.43 expected, standardized incidence ratio (SIR) = 1.10, 95% confidence limit (CI) 1.03‐1.18. There was an excess for cancer of the stomach, rectum, larynx, and lung and nonmelanoma skin cancer; the SIRs were 1.29, 1.44, 1.77, 1.61, and 1.51, respectively. When analyzing the cancer incidence according to length of employment, the SIRs for many of the cancer sites were high for those with a short employment and many SIRs decreased with increasing length of employment. The SIRs for lung cancer were high in all subgroups. Only for stomach cancer and leukemia was there a substantial increase in SIR with increasing length of employment. The SIR was 1.55 for stomach cancer (CI 1.01‐2.27) in the group with longer than 10 years of employment, and 1.97 for leukemia (CI 0.85‐3.87) in the same group. It is concluded that the risk of both stomach and lung cancer seems to be associated with the occupation

ISSN:0271-3586    

DOI:10.1002/ajim.4700270204

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

年代:1995

数据来源: WILEY

摘要:

AbstractThis study uses the National Mortality Followback Survey of 1986 to identify the top five Sentinel Health Events Occupational [SHE(O)s], the five leading causes of death, and to ascertain the primary occupations and industries associated with these. We found that, as expected, cardiovascular diseases were four of the five leading causes of death overall. In addition, the SHE(O) responsible for most deaths was cancer of the trachea, bronchus, and lung, followed by renal failure, bladder cancer, myeloid leukemia, and liver cancer. We employed proportionate mortality ratios to analyze the relationship between industry and occupation and category of mortality. In brief, we validated findings by other researchers; for example, farmers were at lower risk of cancer of the trachea, bronchus, and lung, and workers in eating/ drinking places had excess risk of liver cancer. We also hypothesize other relationships, such as between motor vehicle dealers and bladder cancer.

ISSN:0271-3586    

DOI:10.1002/ajim.4700270205

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

年代:1995

数据来源: WILEY

摘要:

AbstractTissue from an individual with a history of exposure to asbestos and other dust was referred for particulate analysis. The digested material was reviewed by light microscopy to establish the numbers of ferruginous bodies per gram of tissue. Typical asbestos bodies were found at levels consistent with occupational exposure. A second type of elongated ferruginous body was formed on a thicker transparent core which suggested the minerals were sheet silicates. The number of ferruginous bodies with nonasbestos cores was over four times the number of asbestos cored ferruginous bodies.Electron microscopy was used to confirm the core composition of both populations and also to establish the levels of uncoated fibers. The nonasbestos ferruginous bodies were predominantly formed on talc.

ISSN:0271-3586    

DOI:10.1002/ajim.4700270206

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

年代:1995

数据来源: WILEY

摘要:

AbstractWe have updated a study of 3,328 gold miners who worked underground for at least 1 year between 1940‐1965 in South Dakota, extending the follow‐up from 1977 to 1990. The exposures of concern were silica and nonasbestiform amphibole minerals. The lung cancer standardized mortality ratio (SMR) was 1.13 (95% confidence interval [CI] 0.94‐1.36, 115 observed) when the U.S. population was used as the referent group, increasing to 1.25 (95% CI 1.03‐1.51) when the county was used as the referent, and to 1.27 (1.02‐1.55) for person‐time with more than 30 years potential latency. However, lung cancer mortality did not show a positive exposure‐response trend with estimated cumulative dust exposure. Data on smoking habits suggested that the miners smoked slightly more than the U.S. population in a 1960 cross‐sectional survey. In contrast to lung cancer, other diseases known to be associated with silica exposure (tuberculosis and silicosis) were significantly increased (SMR = 3.44 and 2.61) and exhibited clear exposure‐response trends. Nonmalignant renal disease, also associated with silica exposure, was elevated for those hired in early years and showed a significant positive exposure‐response trend. Multiple‐cause analysis revealed significant excesses of arthritis, musculoskeletal diseases (including systemic lupus and sclerosis), and skin conditions (including scleroderma and lupus), diseases of autoimmune origin which have been associated with silica exposure in other studies. Multiple cause analysis also showed a significant excess of diseases of the blood and

ISSN:0271-3586    

DOI:10.1002/ajim.4700270207

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

年代:1995

数据来源: WILEY

摘要:

AbstractThe neurobehavioral effects of lead (organic and inorganic) and organic solvents were compared in 386 U.S. workers (52 reference, 190 lead, and 144 solvent workers). The association between neurobehavioral test performance and duration of exposure to lead or solvents was also examined and compared. The neurobehavioral test battery consisted of examiner and computer‐administered neurobehavioral tests, a test of olfactory function, and questionnaires that assessed neuropsychiatric symptoms. Adjusted mean differences on the neurobehavioral test scores were estimated by comparing the exposed group to the referent group using linear regression and adjusting for premorbid intellectual ability, age, and race. Both lead and solvents were associated with diminished neurobehavioral performance in all neurobehavioral areas tested. Specifically, while lead and solvent exposure had the same magnitude of adverse effects on tests of manual dexterity, lead exposure was associated with greater adverse effects on memory and learning tests but with less adverse effects on executive/motor tests and on a test of olfaction than solvent exposure. An elevated number of neuropsychiatric symptoms was reported by 7% of the referent group, 43% of the lead group, and 15% of the solvent group. For exposure duration of ⩾10 years, more neurobehavioral decrements were found in the solvent group relative to the lead group. However, for exposure duration of ⩽18 years, the lead group showed more decrements than the solvent group. Overall, these data suggest differences in neurobehavioral functioning between the lead (organic and inorganic) and solvent exposed workers examined in this

ISSN:0271-3586    

DOI:10.1002/ajim.4700270208

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

年代:1995

数据来源: WILEY

摘要:

AbstractStudies concerning the respiratory effects of oil mists are sparse and contradictory. The aim of this study was to determine the respective effects of occupational exposure to straight cutting oils and soluble mineral oils on the prevalence of respiratory symptoms, ventilatory impairment, and bronchial reactivity.The population study consisted of 308 male workers of a large French car‐making plant, including 40 subjects chronically exposed to straight cutting oils (group S), 51 subjects chronically exposed to soluble mineral oils (group E), 139 subjects with chronic dual exposure to straight cutting oils and soluble mineral oils (group D), and 78 unexposed assembly workers used as a control group (group C). Worker evaluation included a standardized questionnaire, measurement of pulmonary function, and a methacholine challenge. Oil mist concentration at the work place was determined by gravimetric analysis. The arithmetic mean concentration was 2.6 ± 1.8 mg/m3. The geometric mean concentration was 2.2 pm 1.9 mg/m3.The prevalence of respiratory symptoms did not differ significantly among the four groups. However, the subjects exposed to straight cutting oils (group S + group D) had a significantly higher prevalence of chronic cough and/or phlegm than the others (group E + group O): 25.7% vs. 16.3% (p = 0.048). Furthermore, the prevalence of cough and/or phlegm increased significantly (p = 0.03) with increasing duration of exposure to straight cutting oils after adjustment on smoking categories. Lung function tests did not differ significantly among the four groups but we observed a significant decrease of forced expiratory volume in 1 see (FEV1), forced expiratory flow during the middle half of forced vital capacity (FEF25‐75), and maximal flow rate at 50% and 25% of exhaled forced vital capacity (V50and V25) according to duration of exposure among smokers exposed to straight cutting oils, suggesting a synergistic effect of tobacco and insoluble oils. No effect of exposure to mineral oils on bronchial reactivity was demonstrated.It is concluded that despite low levels of pollution by oil mists, the present study has shown tenuous adverse chronic effects of straight cutting oils on respiratory symptoms and lung function. However, no adverse effect of soluble mineral oils was demonstrated. These results suggest that threshold limit values for mineral oils should be reasse

ISSN:0271-3586    

DOI:10.1002/ajim.4700270209

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

年代:1995

数据来源: WILEY

摘要:

AbstractThe association between occupational exposure to asbestos and histological type of lung cancer was analyzed in a multicenter hospital‐based case‐control study (2,871 male cases and 5,240 male controls) conducted from 1981‐1991. Twenty‐two percent of cases and 18% of controls were employed in asbestos‐related occupations for at least 1 year. Most of these asbestos jobs were in the construction field. The odds ratio (OR) among current smokers was 1.0 [95% confidence intervals (CI) 0.9 to 1.3]; for ex‐smokers, the OR was 1.4 (95% CI 1.1 to 1.6). In contrast, 10% of cases and 5% of controls self‐reported that they were chronically exposed to asbestos for at least 1 year. Self‐reported asbestos exposure was significantly related to all lung cancer cell types among smokers and ex‐smokers, although a trend in the ORs with duration of self‐reported exposure was not found for current smokers. Among 48 cases and 52 controls reporting distinct exposure to building insulation, the OR was 2.2 (95% CI 1.2 to 4.3) for current smokers, and 1.8 (95% CI 0.9 to 3.6) for ex‐smokers, compared to subjects who were not exposed to building insulation and asbestos. A nonsignificant association with self‐reported exposure to asbestos was observed for a small number of never smokers (eight of 83 nonsmoking cases, OR = 2.0, 95% CI 0.9 to 4.6). When examining these results and their causal implications, possible misclassification and reporting biase

ISSN:0271-3586    

DOI:10.1002/ajim.4700270210

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

年代:1995

数据来源: WILEY

摘要:

AbstractPattern visual, brainstem auditory, and somatosensory evoked potential (EP) studies were performed on 26 chloralkali workers. The intensity of mercury vapor exposure in these workers was estimated from the individual working history. Mercury levels in blood, urine, and hair were determined with atomic absorption spectrometry. The EP findings were compared with those from individually matched normal subjects. In brainstem auditory and somatosensory EP studies, prolonged neural conduction times in the central nervous system (CNS) were found in workers exposed to mercury vapor. In the pattern visual EP study, mercury workers had higher interpeak amplitudes. Findings of this study suggested that chronic exposure to mercury vapor would affect the CNS functions. A multimodality EP study is a useful adjunct in evaluation of chronic mercury neurotoxicity, especially in an epidemiological study.

ISSN:0271-3586    

DOI:10.1002/ajim.4700270211

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

年代:1995

数据来源: WILEY