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1.
Sources of asbestos in drinking water may be natural deposits or the use of asbestos cement for water distribution. 50 water samples were selected in Austria to detect fibre contamination from either geology or asbestos cement by comparison with control areas and by comparison of raw and treated water. Standardized EPA/BGA methodology with transmission electron microscopy, energy dispersive X-ray analysis and selected area electron diffraction was used to quantify concentrations of different sized amphibole and chrysotile fibres. In 10 areas with asbestos deposits and in 14 areas with use of asbestos cement pipes asbestos concentrations in drinking water were low and not significantly different from 6 control areas (median 32,000 total asbestos fibres per litre). The relative highest concentration was found in an area with natural deposits at the source of the water supply (190,000 per litre). In areas without natural deposits the increase of asbestos concentrations from origin to consumer of water was not significant and unrelated to water aggressiveness, age and length of asbestos cement pipes. This could be mainly due to the fact that in areas with aggressive water asbestos cement pipes have been coated in Austria. A sample from a cistern, however, showed considerable asbestos contamination and raises concern about the use of surface water for room air humidification.  相似文献   

2.
OBJECTIVES: Syphilis in the United States is focally distributed, with high incidence rates in the South and in metropolitan areas nationwide. In this study an ecological analysis, using the county as the unit of analysis, was performed to generate hypotheses about community-level determinants of syphilis rates. METHODS: Bivariate rank correlations and multivariate, backward stepwise elimination linear regressions were performed. Mean annual incidence of primary- and secondary-stage syphilis in a county was the dependent variable, and county sociodemographic characteristics (from census data) were the independent variables. RESULTS: In the multivariate regression model, sociodemographic characteristics accounted for 71% of the variation in syphilis rates among counties. With other factors accounted for, the most highly correlated characteristics were percentage non-Hispanic Black population, county location in the South, percentage of the population that was urban, percentage Hispanic population, and percentage of births to women younger than 20 years. CONCLUSIONS: Most of the variation in syphilis rates among counties is accounted for by sociodemographic characteristics. Identification and remediation of modifiable health determinants for which these factors are markers are needed to improve the health status of these populations.  相似文献   

3.
OBJECTIVES: To examine the causes of death among 1130 former workers of a plant in Tyler, Texas dedicated to the manufacture of asbestos pipe insulation materials. This cohort is important and unusual because it used amosite as the only asbestiform mineral in the production process. High level exposure of such a specific type was documented through industrial hygiene surveys in the plant. METHODS: Deaths were ascertained through various sources including data tapes from the Texas Department of Health and the national death index files. As many death certificates as possible were secured (304/315) and cause of death assigned. After select exclusions, 222 death certificates were used in the analysis. Causes of death were compared with age, race, and sex specific mortalities for the United States population with a commercial software package (OCMAP Version 2.0). RESULTS: There was an excess of deaths from respiratory cancer including the bronchus, trachea, and lung (standardised mortality ratio (SMR) 277 with 95% confidence interval (95% CI) 193 to 385). Four pleural mesotheliomas and two peritoneal mesotheliomas were identified. The analysis also showed an increasing risk of respiratory malignancy with increased duration of exposure including a significant excess of total deaths from respiratory cancer with less than six months of work at the plant (SMR 268 with 95% CI 172 to 399). CONCLUSIONS: The importance of the cohort lies with the pure amosite exposure which took place in the plant and the extended period of latency which has followed. The death certificate analysis indicates the pathogenicity of amosite, the predominant commercial amphibole used in the United States. These data confirm a link between amosite asbestos and respiratory malignancy as well as mesothelioma.  相似文献   

4.
A case-control study of nasal cancer, based on death certificate statements on occupation in North Carolina counties with furniture-manufacturing industries, revealed a 4-fold excess risk linked to this occupation. Although woodworking exposures have been associated with nasal adenocarcinomas in several areas of the world, this is the first report of such a relationship in the United States.  相似文献   

5.
Exposure to the carcinogen asbestos is a major factor in the development of malignant mesothelioma. However, not all mesotheliomas are associated with asbestos exposure, and only a small minority of people exposed to asbestos develop mesothelioma. Therefore, the identification of the cofactors that render certain individuals more susceptible to asbestos or that cause mesothelioma in people not exposed to asbestos has been a major priority of the International Mesothelioma Interest Group. The possible association of SV40 with mesothelioma was recently discussed in a special session at the Fourth International Mesothelioma Interest Group Conference, and it was decided to conduct a multi-institutional study to independently verify the presence of this tumor virus in mesotheliomas. We report the results of this investigation: (a) DNA and protein analyses revealed SV40 sequences and SV40 large T antigen expression in 10 of 12 mesotheliomas tested (83%); and (b) electron microscopy demonstrated variable amounts of asbestos fibers in 5 (71%) of 7 corresponding lung tissues available for analysis. Our results demonstrate that SV40 DNA is frequently present and expressed in mesotheliomas in the United States. Because our data demonstrate that some patients test positive for both SV40 and asbestos, the possibility that these two carcinogens interact should be investigated in future studies.  相似文献   

6.
Malignant mesothelioma is caused almost exclusively by occupational exposure to asbestos. During the past few years, however, increasing evidence has mounted that background exposure to asbestos could be sufficient to cause mesothelioma. Treatment of malignant mesothelioma remains a big problem. Some new approaches are on their way, and the most exciting ones are local immunotherapy in very early cases. Some success has been reported with local interferon treatment. As for treatment of metastatic pleural disease, the main purpose is symptomatic relief of dyspnea caused by fluid accumulation. The best way to achieve a lasting palliation is pleurodesis, and the most common way to do this, is by chemical means. The drug of choice in the United States has for many years been tetracycline, but since injectable tetracycline is no longer available, some substitute must be found. The substance that will "win" is not yet clear, but the two leading contestants are talc and doxycycline. Bleomycin also has its supporters, and a dark horse is quinacrine, which although not easily available in the United States, has been used in many European centers for decades.  相似文献   

7.
Because of the reduced risk of ovarian cancer related to prior full-term pregnancies, we sought to determine whether there was any association with a history of one or more incomplete pregnancies. White female residents of three counties in Washington State (United States) diagnosed with ovarian cancer during 1986-88 (n = 322), and a random sample of control women selected from these same counties (n = 426), were interviewed regarding their pregnancy and childbearing histories. Among women who had given birth to at least one child, an additional incomplete pregnancy was not associated with the risk of ovarian cancer (relative risk [RR] = 1.1, 95 percent confidence interval [CI] = 0.8-1.6, adjusting for age, oral contraceptive use, and number of births). For those who had never given birth, a somewhat smaller proportion of cases had a history of incomplete pregnancy than controls (RR = 0.8, CI = 0.4-1.7). In an analysis restricted to ever-pregnant women, a prior induced or spontaneous abortion was not found to be associated with the incidence of ovarian tumors (RR = 1.0, CI = 0.6-1.7, and RR = 1.3, CI = 0.8-1.9, respectively). Other studies of the possible relation between incomplete pregnancies and ovarian cancer generally have observed either a weak negative association or no association at all. It is possible that if incomplete pregnancies do affect the risk of ovarian cancer, their impact might be too small to be identified reliably through epidemiologic studies.  相似文献   

8.
Hands-on engineering education is an upcoming trend among K-12 schools throughout the United States to stimulate interest in science, technology, engineering, and mathematics (STEM). This study used unconventional methods to stimulate interest in STEM fields among high school students in a rural county of Tennessee. First, the study began by assessing enrollment data from each of Tennessee’s 95 counties to determine the factors that influenced the decision by high school applicants to choose engineering at Tennessee Technological University (TTU). The findings revealed that, while there were no significant differences between the aptitude scores of applicants from rural and urban counties, TTU had a higher representation of freshmen from urban areas. This indicated that motivational programs targeted at counties with low population, income level, and education level were needed to boost enrollment from rural counties. As a response, we introduced next a hands-on engineering class at Jackson County High School (JCHS) that was tied to the national-level program called “Project Lead the Way.” With JCHS lying in a rural setting right along the Cumberland River, an engineering risk study was completed in front of the class to demonstrate the risk of failure of the Wolf Creek Dam (in Kentucky), which lies upstream. The idea was to leverage a real-world engineering infrastructure and a natural hazard phenomenon (overflooding) that had direct and visible implications on the lives of the county, as a way to promote the societal value of STEM disciplines to students at JCHS. These efforts were monitored through a series of pre- and posttests to determine the effectiveness of the hands-on teaching methods and engineering risk analysis of a real-world infrastructure. The testing efforts showed a significantly positive impact on student perception of STEM fields in pursuit of engineering innovation. Student assessment of perceptions of engineering proved that the use of real-world water risk analysis of a nearby infrastructure as a motivational tool in a rural high school setting is very effective to boost awareness of STEM fields and engineering.  相似文献   

9.
OBJECTIVES: In this study, cancer survival rates for patients diagnosed in Ontario and selected areas within the United States were compared. METHODS: Relative survival rates were computed for patients aged 15 through 84 years diagnosed with any of four forms of cancer (breast, colon, lung, and Hodgkin's disease). The cohorts represented those diagnosed over the years 1978 through 1986 in the Canadian province of Ontario and in nine regions covered by the US National Cancer Institute's Surveillance Epidemiology and End Results program. Patients were followed through the end of 1990. RESULTS: The cumulative relative survival rates were similar for American and Canadian patients. The largest difference was observed for breast cancer, where patients in the United States enjoyed a survival advantage throughout the follow-up period. CONCLUSIONS: Patients in the United States and Ontario with the diseases studied, except for breast cancer, experience very similar survival. The greater use of mammographic screening in the United States could account for that country's higher breast cancer survival rate by promoting earlier and therefore more efficacious treatment, by introducing bias, or by a combination of both treatment and bias factors.  相似文献   

10.
OBJECTIVE: To examine the characteristics of foreign-born people with tuberculosis (TB) in Southern Florida, their contribution to the total number of TB cases, and available data on their HIV status as well as to determine the number of cases detected by the overseas medical screening of immigrants and refugees. METHODS: The authors reviewed TB cases reported by Broward, Dade, and Palm Beach counties in 1995. Case records were matched against the CDC Division of Quarantine database of immigrants and refugees suspected to have TB at the time of visa application overseas. RESULTS: Nearly half (49%) of TB cases in the three counties were among people born outside the United States--34% in Broward County, 58% in Dade County, and 40% in Palm Beach County. A high percentage (26%) were co-infected with HIV. Of those with known date of arrival, 68% had been in the United States for five or more years. Only three cases had been identified by overseas immigrant screening. CONCLUSIONS: A low percentage of TB cases in foreign-born people were identified through the overseas screening system. Controlling TB in South Florida will require efforts targeted toward high risk populations, including people with HIV infection.  相似文献   

11.
"A questionnaire covering various value sentiments and a picture-story test for measuring n Achievement and n Affiliation were administered to 87 German and 74 United States male students preparing for college who had been carefully matched for age (around 18 years) and socio-economic background (largely upper middle class). A factor analysis of the questionnaire results yielded two factors that could be matched in the two countries and a third set of items that shifted from one factor to the other across countries. The 'switchover' items which dealt largely with decency and obligation to others were associated with Factor A ('rational striving') in Germany and were more strongly accepted by the Germans than by the Americans, as were also the Factor A items. In the United States, the switch-over items were associated with Factor B ('resigned cynicism') suggesting that acceptance of statements about strong obligations to others tend to be associated in the United States with a kind of deviant 'Un-American' passive resignation." (17 ref.) From Psyc Abstracts 36:01:1GB45M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
OBJECTIVES: To evaluate alternative models and estimate risk of mortality from lung cancer and asbestosis after occupational exposure to chrysotile asbestos. METHODS: Data were used from a recent update of a cohort mortality study of workers in a South Carolina textile factory. Alternative exposure-response models were evaluated with Poisson regression. A model designed to evaluate evidence of a threshold response was also fitted. Lifetime risks of lung cancer and asbestosis were estimated with an actuarial approach that accounts for competing causes of death. RESULTS: A highly significant exposure-response relation was found for both lung cancer and asbestosis. The exposure-response relation for lung cancer seemed to be linear on a multiplicative scale, which is consistent with previous analyses of lung cancer and exposure to asbestos. In contrast, the exposure-response relation for asbestosis seemed to be nonlinear on a multiplicative scale in this analysis. There was no significant evidence for a threshold in models of either the lung cancer or asbestosis. The excess lifetime risk for white men exposed for 45 years at the recently revised OSHA standard of 0.1 fibre/ml was predicted to be about 5/1000 for lung cancer, and 2/1000 for asbestosis. CONCLUSIONS: This study confirms the findings from previous investigations of a strong exposure-response relation between exposure to chrysotile asbestos and mortality from lung cancer, and asbestosis. The risk estimates for lung cancer derived from this analysis are higher than those derived from other populations exposed to chrysotile asbestos. Possible reasons for this discrepancy are discussed.  相似文献   

13.
The Environmental Health and Safety Council of the American Health Foundation has examined current estimates of cancer risks associated with the presence of asbestos-containing materials (ACM) in public buildings. The Council finds that even complete removal of asbestos from all of these buildings will provide no measurable benefit to public health. The removal of nonfriable ACM only can be postulated to protect the public against a small hypothetical risk that cannot be measured epidemiologically. Moreover, examination of the assumptions used in the risk assessment calculations leads to the conclusion that these small calculated risks are likely to represent overestimates. In recent surveys, the measured asbestos levels in indoor air cast some doubt on whether occupant exposure to asbestos levels are contributed to significantly by ACM even when some of the material is friable or in bad condition. Furthermore, the models used for cancer risk estimates assume no threshold level for cancer and conclude that any exposure is carcinogenic. This may be unjustified in light of information on the mechanisms for some asbestos-caused disease. Based on the best available data, it is very unlikely that cancer will result from indoor asbestos exposure, especially where ACM is well maintained.  相似文献   

14.
The New York City neighborhood of Harlem has mortality rates that are among the highest in the United States. In absolute numbers, cardiovascular disease and cancer account for the overwhelming majority of deaths, especially among men, and these deaths occur at relatively young ages. The aim of this research was to examine self-reported smoking habits according to measures of socioeconomic status among Harlem men and women, in order to estimate the contribution of tobacco consumption to Harlem's remarkably high excess mortality. During 1992-1994, in-person interviews were conducted among 695 Harlem adults aged 18-65 years who were randomly selected from dwelling unit enumeration lists. The self-reported prevalence of current smoking was strikingly high among both men (48%) and women (41%), even among highly educated men (38%). The 21% of respondents without working telephones reported an even higher prevalence of current smoking (61%), indicating that national and state-based estimates which rely on telephone surveys may seriously underestimate the prevalence of smoking in poor urban communities. Among persons aged 35-64 years, the smoking attributable fractions for selected causes of death were larger in Harlem than in either New York City as a whole or the entire United States for both men and women. Tobacco consumption is likely to be one of several important mediators of the high numbers of premature deaths in Harlem.  相似文献   

15.
Pleuropulmonary cancers are recognized asbestos-related diseases. Mesothelioma occurs almost uniquely in individuals exposed to asbestos whereas lung cancer is strongly associated with smoking. If the asbestos exposure is sufficient however, the incidence of lung cancer is higher than would be expected from the smoking effect alone. For lung cancer in asbestos workers, asbestosis is not a prerequisite for recognition as an occupation-related disease. The intensity and duration of exposure to asbestos are factors associated with higher risk of lung cancer. These factors can be estimated on the basis of the work history or, when necessary, by analyzing mineral dust from available lung tissues.  相似文献   

16.
To evaluate predictors of contralateral breast cancer risk, we examined data from a nested case-control study of second primary cancers among a cohort of women in western Washington (United States) diagnosed with breast cancer during 1978 through 1990 and identified through a population-based cancer registry. Cases included all women in the cohort who subsequently developed contralateral breast cancer at least six months after the initial diagnosis, but prior to 1992 (n = 234). Controls were sampled randomly from the cohort, matched to cases on age, stage, and year of initial breast cancer diagnosis. Information on potential risk factors for second primary cancer was obtained through medical record abstractions and physician questionnaires. Women who were postmenopausal due to a bilateral oophorectomy (i.e., a surgical menopause) at initial breast cancer diagnosis had a reduction in contralateral breast cancer risk compared with premenopausal women (matched odds ratio [mOR] = 0.25, 95 percent confidence interval [CI] = 0.09-0.68), whereas no reduction in risk was noted among postmenopausal women who had had a natural menopause (mOR = 0.90, CI = 0.39-2.09). Among postmenopausal women, there was a suggestion of a lower risk associated with relatively high parity (2+). A family history of breast cancer was associated with an increased risk (mOR = 1.96, CI = 1.22-5.15) and varied little by menopausal status. Having an initial tumor with a lobular component (c.f. a ductal histology) was not related strongly to risk (mOR = 1.47, CI = 0.79-2.74). The results of the present and earlier studies argue that we have limited ability to predict the occurrence of a contralateral breast tumor. Better predictors will be required before diagnostic and preventive interventions can be targeted to subgroups of patients with unilateral breast cancer.  相似文献   

17.
Although the incidence of gastric cancer varies widely between countries it is nonetheless a leading cause of cancer deaths worldwide. Migration studies indicate that dietary choices are an important exogenous factor. The United States has a very low incidence of gastric cancer, suggesting that exogenous etiological agents are at a minimum and providing a favorable setting for detecting important endogenous etiological factors. Dehydroepiandrosterone and dehydroepiandrosterone sulfate are endogenous steroids produced in the adrenal gland. Epidemiological studies show that the risk of developing specific cancers is related to the serum or urinary levels of these steroids. In addition, dehydroepiandrosterone prevents a variety of spontaneous and chemically induced tumors when administered to laboratory animals. To examine the association between circulating levels of dehydroepiandrosterone and dehydroepiandrosterone sulfate and the development of gastric cancer, we measured the serum levels of these steroids in 13 individuals who donated serum to the Washington County Maryland serum bank in 1974 and who subsequently developed gastric cancer and in 52 matched controls. Prediagnostic serum levels of dehydroepiandrosterone were 38% lower in cases as compared to controls (P = 0.09). The risk of developing gastric cancer increased with decreasing levels of both steroids. Adjustment for confounding factors such as smoking or the interval between blood donation and time to diagnosis did not alter the findings. These results suggest that there may be a role for this steroid in the prevention of gastric cancer.  相似文献   

18.
Abortion incidence and services in the United States, 1995-1996   总被引:1,自引:0,他引:1  
CONTEXT: In the 1980s, the number of abortion providers in the United States began to decline, and more recently, so has the number of abortions performed. Whether the decline in service providers, which was last documented in 1992, is continuing and whether this influences the availability and number of abortions is of public interest. METHODS: In 1997, the Alan Guttmacher Institute conducted its 12th survey of all known abortion providers in the United States. The number and location of abortion providers and abortions were tabulated for 1995 and 1996, and trends were calculated by comparing these data with those from earlier surveys. Limited data were also gathered on types of abortion procedures. RESULTS: Between 1992 and 1996, the number of abortions fell from 1,529,000 to 1,366,000, and the abortion rate decreased from 26 to 23 per 1,000 women aged 15-44. The number of providers fell 14%, to 2,042, with the greatest decline among hospitals and physicians' offices rather than clinics. Eighty-six percent of counties had no known abortion provider, and 32% of women aged 15-44 lived in these counties. Of the country's 320 metropolitan areas, 89 had no known abortion provider, and for an additional 12, fewer than 50 abortions each were reported. Seventy percent of abortions were performed in specialized clinics and only 7% in hospitals. In the first half of 1997, early medical abortions were being offered in about 160 facilities, virtually all of which were also providers of surgical abortions. CONCLUSIONS: While abortion services in some areas of the country have declined since 1992 and many women continue to have limited access to providers, other factors have probably had more influence on the level of abortions performed. Early medical abortion methods are too new to be a measurable factor in abortion access.  相似文献   

19.
Owing to its particular properties asbestos has been widely used for the production of insulating material, for fire proofing, and for strengthening to other materials such as cements and plastics, and thus the story of this mineral was one of progressive commercial success until the middle of this century. However, serious health hazards were realized early: around the turn of the century a progressive form of diffuse fibrosis (asbestosis) in asbestos workers was observed and in 1950 an excess risk of lung cancer, while in 1960 the causal relationship between asbestos and mesothelioma were confirmed. In view of the known potential risks of asbestos and its widespread use in the building industry, more recently asbestos has caused considerable public concern and anxiety. Based on numerous experimental and epidemiological observations, present knowledge of the pathogenic effects of asbestos is sufficient for a number of broad conclusions to be drawn. (1) The amphibole types of asbestos are too dangerous for use as industrial material, and should be banned. (2) Chrysotile can probably be used safely if there is strict control of the workers' dust exposure. (3) It is very unlikely that the general public is at any measurable risk from asbestos in buildings. Exceptions are people working regularly on maintenance tasks involving removing or cutting of asbestos in buildings; such people are properly classified as asbestos workers and should be protected accordingly.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
BACKGROUND: Among the victims of floods, earthquakes, and hurricanes, there is an increased prevalence of post-traumatic stress disorder and depression, which are risk factors for suicidal thinking. We conducted this study to determine whether natural disasters affect suicide rates. METHODS: From a list of all the events declared by the U.S. government to be federal disasters between 1982 and 1989, we selected the 377 counties that had each been affected by a single natural disaster during that period. We collected data on suicides during the 36 months before and the 48 months after the disaster and aligned the data around the month of the disaster. Pooled rates were calculated according to the type of disaster. Comparisons were made between the suicide rates before and those after disasters in the affected counties and in the entire United States. RESULTS: Suicide rates increased in the four years after floods by 13.8 percent, from 12.1 to 13.8 per 100,000 (P<0.001), in the two years after hurricanes by 31.0 percent, from 12.0 to 15.7 per 100,000 (P<0.001), and in the first year after earthquakes by 62.9 percent, from 19.2 to 31.3 per 100,000 (P<0.001). The four-year increase of 19.7 percent after earthquakes was not statistically significant. Rates computed in a similar manner for the entire United States were stable. The increases in suicide rates were found for both sexes and for all age groups. The suicide rates did not change significantly after tornadoes or severe storms. CONCLUSIONS: Our study shows that suicide rates increase after severe earthquakes, floods, and hurricanes and confirms the need for mental health support after severe disasters.  相似文献   

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