Mortality patterns among workers exposed to styrene in the reinforced plastic boatbuilding industry: an update

BACKGROUND: Mortality was updated through 1998 for 5,204 workers exposed to styrene between 1959 and 1978 at two reinforced plastic boatbuilding plants. The a priori hypothesis: leukemia and lymphoma excesses would be found. METHODS: Standardized mortality ratios (SMR) and 95% confidence intervals (CI) used Washington State and U.S. rates. RESULTS: Overall, 860 deaths occurred (SMR 1.09, CI 1.02-1.17), with excess mortality for esophageal cancer (n = 12, SMR 2.30, CI 1.19-4.02), prostate cancer (n = 24, SMR 1.71, CI 1.09-2.54), and accidents (n = 99, SMR 1.26, CI 1.02-1.53). Among 2,062 highly exposed workers, urinary tract cancer (n = 6, SMR 3.44, CI 1.26-7.50) and respiratory disease (n = 12, SMR 2.54, CI 1.31-4.44) rates were elevated. Urinary tract cancer SMR increased with duration of employment. CONCLUSIONS: We found no excess leukemia or lymphoma mortality. Unanticipated excess urinary tract cancer and respiratory disease mortality, possibly associated with styrene exposure, are difficult to interpret and could be chance findings.     

Exposure to volatile organic compounds in residences adjacent to dyeing industrial complex

Objectives The present study was designed to evaluate residential exposure to selected volatile organic compounds (VOCs) relative to the proximity of the Daegu dyeing industrial complex (DDIC).Methods A series of surveys was conducted to measure the concentrations of five aromatic VOCs (toluene, benzene, m-xylene, p-xylene, and o-xylene) and methyl tertiary-butyl ether (MTBE) in the industrial outdoor air within the DDIC and in residential outdoor and indoor air based on the relative proximity of the DDIC.Results The geometric mean (GM) toluene value for the outdoor air samples from residential area R1 located near the DDIC (255 g/m³) was about seven-times higher than that from residential area R2 located further away from the DDIC (36.9 g/m³), whereas no significant difference was found in the outdoor air concentrations of the other target compounds between the two residential areas. Moreover, the elevated outdoor toluene levels outweighed the indoor sources with respect to the environmental exposure of residents near the DDIC. However, for the other target VOCs there was no significant difference between the residential exposure of residents living close to and a certain distance away from the DDIC.Conclusions The present study confirmed that residents in neighborhoods near the DDIC were exposed to elevated outdoor toluene levels compared with residents living further away from such a source. Furthermore, it appeared that the DDIC was a potential contributor to the nearby residential outdoor toluene levels.Essential results have not been and will not be published elsewhere     

Improving system quality through software evaluation

The role of evaluation is examined with respect to quality of software in healthcare. Of particular note is the failure of the Therac-25 radiation therapy machine. This example provides evidence of several types of defect which could have been detected and corrected using appropriate evaluation procedures. The field of software engineering has developed metrics and guidelines to assist in software evaluation but this example indicates that software evaluation must be extended beyond the formally defined interfaces of the software to its real-life operating context.     

Lung function decrease in relation to pneumoconiosis and exposure to quartz-containing dust in construction workers

BACKGROUND: Prevalence of exposure related respiratory symptoms and decreases in lung function are unknown among quartz dust exposed construction workers. METHODS: In a cross-sectional study (n = 1335), the occurrence of respiratory symptoms, was recorded and spirometric lung function was measured. Results were associated with exposure data and presence of radiographic abnormalities and compared with a reference population. RESULTS: Pneumoconiosis (profusion category 1/1 or greater) was associated with increased risks of FEV(1) and FVC values in the lowest 5% group, and with group-based decreases of 270 ml/s and 180 ml, respectively. Average lung function of construction workers was somewhat lower compared to a Dutch reference population. Lung function was not associated with exposure, except for a reduction in FVC of 5 ml per year for those with higher exposure. CONCLUSIONS: In quartz dust exposed construction workers obstructive and restrictive lung function loss was detected.     

Multiple myeloma and diesel and other occupational exposures in swedish construction workers

We examined the relationships between occupational exposures and the risk of multiple myeloma among male construction workers in Sweden. A total of 446 myeloma subjects were identified among 365,424 male workers followed from 1971 to 1999. Occupational exposure was assessed using a semiquantitative job-exposure matrix, based on a survey carried out by the Construction Industry's Organization for Working Environment, Occupational Safety and Health in Sweden. Rate ratios (RRs) in the exposed groups relative to the unexposed groups were estimated by Poisson regression. We found an increased risk (RR = 1.3, 95% CI 1.04-1.71) among construction workers exposed to diesel exhaust. Adjustment for other occupational exposures did not change this estimate (RR = 1.3, 95% CI 1.00-1.77). However, there was no monotonic increase in risk with estimated level of exposure (RR for low = 1.4, moderate = 1.1, high = 1.4). There was no evidence of increased risk associated with the other occupational exposures among these construction workers, including asbestos, asphalt, cement dust, metal dust, mineral wool, organic solvents, stone dust and wood dust. Occupational exposure to diesel exhaust in the Swedish construction industry may present a small risk of multiple myeloma, but lack of an exposure-response trend tempers our ability to draw clear conclusions.     

控制卫生费用 还是投资于健康--兼论健康产业模式

探讨我国卫生和卫生系统与经济的关系。由于政府、社会和病人无法承受越来越高的卫生费用,以至于控制卫生费用已成为我国卫生政策的核心。而作者从另一角度阐述健康投资对于宏观经济发展的价值与贡献。通过分析我国近年来的人群健康状况、卫生资源和卫生费用等的变化发展趋势,发现在有限的卫生费用下总体健康状况持续改善。提出了投资于健康有利于降低疾病负担,提高劳动生产力,从而促进经济的发展。     

What do we really know about conflicts of interest in biomedical research?

Rationale Conflicts of interest in research have long been seen to pose serious threats to the integrity of research. Indeed, the past two decades have revealed increased attention to the possible influence of conflicts of interest as the number of research studies funded by private industry have increased.Objectives We review empirical findings directly pertinent to issues concerning financial conflicts of interest in biomedical research, and we provide an overview of the current issues and state of understanding concerning such conflicts in research.Methods We searched Medline from January 1992 to January 2002 to locate current studies that have reported primary or secondary empirical data pertaining to conflicts of interest in research.Results The rate of potential conflicts of interest for researchers appears to be at least 30% in some situations although the accuracy of such a rate is untested, and the rate of disclosure of conflicts of interest is as low as 2%. Furthermore, some evidence exists to indicate that researchers with conflicting interests may indeed offer different professional opinions and judgments than those for whom such conflicts do not exist. The effectiveness of various disclosure and management methods for conflicts of interest is unknown.Conclusions We summarize the current empirical literature, concluding that relatively little is known based on such data. We suggest a number of questions that need to be answered by future research, and we offer recommendations for policy makers to consider and evaluate in the future in identifying, revealing, and managing conflicts of interest.