摘要:

AbstractTwo pivotal problems in determining whether exposure to herbicides has caused disease in Vietnam veterans or their offspring are definition of which troops were exposed and extent of exposure. The DoD HERBS tape is the most complete publicly available record of herbicide spraying in Vietnam. It contains about 17,000 records consisting of coordinates of spray missions, dates, chemical agent, quantity and area sprayed, and mission purpose. We have developed a set of discrete and continuous indexes of probability of exposure to herbicides for individual veterans. These probability indexes are based on HERBS tape spray data and on locations and dates of service derived from a place‐and‐date matrix completed by the veteran. They can take into account a conservative estimate of environmental persistence of herbicide by using first‐order exponential decay kinetics with an estimated half‐life of dioxin. Mean values for the continuous exposure probability indexes were significantly greater among veterans judged to be exposed according to self‐reported job titles and specific military experiences than among men judged unlikely to have been exposed. Probabilistic exposure indexes based on the HERBS tape for classification of likely exposure to herbicides in South Vietnam during 1965–1971 appear to be well suited for comparative classification of veterans and hence for use in epidemiolo

ISSN:0271-3586    

DOI:10.1002/ajim.4700090402

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

年代:1986

数据来源: WILEY

摘要:

AbstractThis investigation is based on a study of 117 men and 24 women with malignant mesothelioma registered by the Cancer Registry of Norway, 1970–79. The age‐adjusted incidence rate in men for each county varied from 1.7 to 13.3 per million per year. Eighty‐two percent of the men revealed possible occupational asbestos exposure. They were evenly distributed between counties with high and low mesothelioma incidence. Only 17% of the women had possible occupational asbestos exposure. Total lung fiber concentration was analyzed with scanning electron microscopy in 65 men and 13 women. The median lung fiber concentration in men was 2.4 million per gram of dried tissue (range<0.4–490), in women 1.0 million per gram (range<0.4–41), and in male controls<0.4 million per gram (range<0.4–4.8). The median year of first exposure was 1937 (range 1909–60) for men from counties with a high incidence rate and 1945 (range 1938–59) for men from counties with a low incidence rate. The counties with a high compared to a low incidence rate of malignant mesothelioma, 1970–79, showed an apparent difference in the percentage of population employed in industry in 1946. The regional variation in the incidence of malignant mesothelioma in men is mainly attributable to the proportion of population exposed to asbestos in industry per county prior to the 1950s and the time since exposure started. Nonoccupational asbestos exposure and nonasbestos agents may be invol

ISSN:0271-3586    

DOI:10.1002/ajim.4700090403

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

年代:1986

数据来源: WILEY

摘要:

AbstractWe undertook a study to determine the acute effects of routine firefighting on lung function and the relationship between these acute effects and nonspecific airway responsiveness. For 29 firefighters from a single fire station, we calculated the concentration of methacholine aerosol that caused a 100% increase in specific airway resistance (Pc100). Over an 8‐week period we then measured FEV1 and FVC in each firefighter before and after each 24‐hr workshift and after every fire. From 199 individual work‐shifts without fires, we calculated the mean ± 2 SD across‐workshift change in FEV1 and FVC for each firefighter. Eighteen of 76 measurements obtained within 2 hr after a fire (24%) showed a greater than 2 SD fall in FEV1 and/or FVC compared to two of 199 obtained after routine workshifts without fires (1%; p<.001). On 13 of 18 occasions when spirometry decreased significantly, we obtained repeat spirometry (post‐shift) 3–18.5 hr after fires, and on four of these occasions FEV1 and/or FVC were still more than 2 SD below baseline. Decrements in spirometry occurred as often in firefighters with high Pc100s as in those with low Pc100s. In two firefighters in whom FEV1 and FVC fell by more than 10% after fires, we repeated measurements of methacholine sensitivity, and it was increased over the prestudy baseline. These findings suggest that routine firefighting is associated with a high incidence of acute decrements in lung function. The persistence of these decrements, the lack of association with baseline airway responsiveness, and the association with acute increases in airway responsiveness all suggest that these decrements in lung function are not due merely to irritant broncho

ISSN:0271-3586    

DOI:10.1002/ajim.4700090404

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

年代:1986

数据来源: WILEY

摘要:

AbstractPhotographic developing processes employ hazardous chemical substances, many with known adverse effects on the respiratory system. Three cases documenting respiratory symptoms and suggesting small airway abnormalities among photographic developers are reported. Work‐related factors which might contribute to these findings, as well as public health implications, are discusse

ISSN:0271-3586    

DOI:10.1002/ajim.4700090405

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

年代:1986

数据来源: WILEY

摘要:

AbstractReversible airways obstruction occurred in a photographer after long‐term exposure (over many years) to sulfuric and acetic acid fixers. Air‐exchange recommendations for darkrooms by the Building Officials Code Administration [1981] differ markedly from those recommended by the American Society of Heating, Refrigerating, and Air‐conditioning Engineers [1977]and the fixer manufacturer (Eastman Kodak). Use of fume hoods or rates of air‐exchange higher than are required by law may be necessary to prevent symptoms and disease in certain

ISSN:0271-3586    

DOI:10.1002/ajim.4700090406

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

年代:1986

数据来源: WILEY

摘要:

AbstractA mortality follow‐up study was conducted of workers employed at a synthetic rubber manufacturing plant in Baton Rouge, Louisiana. Interest in the potential health effects of exposure to methyl chloride, one of the substances used in the manufacturing process, provided the impetus for this study. The study cohort consisted of 852 male process workers who had worked at least 1 month during the period from startup of operations in 1943 through December 31, 1978. Mortality from all causes was lower than expected when compared with the U.S. male population. No excess mortality from any specific cause of death was found in the study population after analysis by level and duration of exposur

ISSN:0271-3586    

DOI:10.1002/ajim.4700090407

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

年代:1986

数据来源: WILEY

摘要:

AbstractAmong 160 consecutive patients referred to the Clinic of Occupational Medicine, Rigshospitalet, for symptoms connected with exposure to organic solvents, 20 exhibited symptoms of acquired intolerance to minor amounts of organic solvents. Later, an additional 30 consecutive patients with symptoms of acquired intolerance were included, yielding a total of 43 men and 7 women. The characteristics of the clinical syndrome described are complaints of dizziness, nausea, and weakness after exposure to minimal solvent vapor concentrations. After having tolerated long‐term occupational exposure to moderate or high air concentrations of various organic solvents, the patients became intolerant within a short period of time. Since dizziness was a frequent complaint, we tried to obtain a measure of the patients' complaints using vestibular tests. As a diagnostic test the combined vestibular tests had a sensitivity of 0.55 and a specificity of 0.87. No differences between patients with and without intolerance could be detected by the vestibular tests used. We conclude that acquired intolerance to organic solvents is a new but characteristic and easily recognizable syndrome, often with severe consequences for the patient's working abilit

ISSN:0271-3586    

DOI:10.1002/ajim.4700090408

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

年代:1986

数据来源: WILEY

摘要:

AbstractIn this study, the cytotoxicity of 13 fibrous samples of known fiber number and dimensions has been established in P388D1cells. The cells were exposed in vitro to dust concentrations of 10 or 50 μg/ml and, after incubation for 24 or 48 hours, any changes in cellular viability, lactate dehydrogenase, and glucosaminidase levels were determined. In general, there was a close association between the reduction in cellular viability and the loss of intracellular enzymes induced by each dust, the chrysotile asbestos samples proving more cytotoxic than the amphiboles. The cytotoxicity of the fibrous dusts was shown to be related to the number of fibers greater than 8 μm in length in the sample

ISSN:0271-3586    

DOI:10.1002/ajim.4700090409

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

年代:1986

数据来源: WILEY

摘要:

AbstractIn monitoring occupational populations with the human lymphocyte cytogenetic test, it is not always possible to collect and process matched samples on the same day, even though this would be desirable to control for technical variables. The effects of holding samples for 24 hours at 4°C and 22°C, freezing lymphocytes in dimethylsulfoxide at −180°C, and keeping fixed cells for 6 days at 4°C before slide‐making were examined. Final cell count, mitotic index, percentage of cells in first division, percentage of cells with chromosomal aberrations, and sister chromatid exchange per cell were measured in paired cultures. A significant increase in the frequency of cells with chromatid breaks occurred after prolonged fixation, so all other results were obtained from freshly fixed cells. Although holding at 22°C and cryopreservation had significant effects on the mitotic index and entry of lymphocytes into the cell division cycle, the cytogenetic endpoints were not affected by any of the sample manipulations. Thus, samples can be held at 4°C or 22°C for 24 hours, or frozen lymphocytes can be stored for at least a week, without altering the cytogenetic

ISSN:0271-3586    

DOI:10.1002/ajim.4700090410

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

年代:1986

数据来源: WILEY

ISSN:0271-3586    

DOI:10.1002/ajim.4700090411

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

年代:1986

数据来源: WILEY