A retrospective mortality study within operating segments of a petroleum company.

This retrospective mortality study was conducted among 34,597 oil industry workers in diverse operating segments. Employees were traced through Statistics Canada, and overall mortality (SMR = 0.85) was lower than general population rates and similar to other petrochemical cohorts. The most notable finding was a significant excess of malignant melanoma [observed deaths (N) = 16, SMR = 1.87, 95% CI = 1.07, 3.04], which concentrated among upstream workers (N = 6, SMR = 6.00, 95% CI = 2.19, 13.06), and was directly related to employment duration and latency. Specific substances or hydrocarbon (HC) streams could not be implicated, although possible explanations include dermal HC exposure, ultraviolet light exposure, or a synergistic effect between these two factors. Marketing/transportation workers showed a non-significant excess of multiple myeloma (SMR = 1.81), which was also related to employment duration, latency, and commencement of employment before 1950. Lymphatic cancer, skin cancer, and kidney cancer mortality was not elevated in refinery workers, a finding at odds with some previous refinery worker studies. Although the malignant melanoma and possibly the multiple myeloma mortality patterns are consistent with an occupational link, further studies are needed to investigate the relationship of these diseases with particular exposures.     

Long-term follow-up mortality study of petroleum refinery and chemical plant employees

A previous report presented the 1948–1983 mortality patterns of the Shell Deer Park Manufacturing Complex employees who where employed for at least 3 months from 1948 through 1972. The present study updates the earlier investigation by extending the vital status follow-up through 1989 and by expanding the cohort to include employees hired after 1972. As in the previous study, the overall mortality and cancer mortality for both refinery and chemical employees were quite favorable compared to residents in the local population. Among refinery workers, cancers for which a suspicion of work-relatedness was raised in the previous study, i.e. leukemia and cancers of the central nervous system and biliary passage/liver, no supportive evidence was found in this update. For both refinery and chemical plant employees, the mortality rate due to cancers of all lymphopoietic tissue increased with increasing duration of employment; this finding was also noted by the original study. This was also evident for lymphoreticulasarcoma in refinery employees and for leukemia in chemical plant employees. However, elevations of cancers of all lymphatic and hematopoietic tissue are primarily confined to employees who started work at the complex before 1946. By contrast, deaths from cancer of all lymphatic and hematapoietic tissue for employees hired after 1945 were 22% lower than the comparison population. Seven deaths with mesothelioma mentioned on the death certificates were identified, with 3.2 deaths expected, resulting in a statistically nonsignicant SMR of 219. © 1996 Wiley-Liss, Inc.     

Fatal occupational injuries among electric power company workers

Surveillance data suggest high rates of electrocutions and fatal falls among workers in electric utility companies, who may be exposed to electric current, heights, flammable agents, and frequent motor vehicle travel. To characterize the occurrence of fatal injuries among electric utility workers, we studied workers in five electric power companies in the United States. A cohort of 127,129 men hired between 1950 and 1986 was followed through 1988. Injuries at work were identified through manual review of death certificates. The occurrence of occupational injuries was analyzed with directly adjusted rates and Poisson regression. The overall rate of fatal occupational injuries was 13.20 per 100,000 person‐years (n = 192), with 76% due to electric current, homicide, and falls from heights. Deaths were concentrated in a few groups with elevated injury rates, notably linemen (rate ratio (RR) 3.33), electricians (RR 2.79), and painters (RR 3.27). Occupations requiring daily work on elevations or frequent, direct contact with energized electrical equipment experienced markedly higher rates of fatal injury from falls and electrocutions with rate ratios of 21.8 (95% confidence interval (CI) 11.4–41.5) and 16.7 (95% CI 6.6–42.6), respectively, independent of worker age and seniority. Although fatal injury rates in this industry have declined in recent decades, significant numbers of deaths still occur. Based on the premise that all injuries are preventable, a need for continued vigilance and efforts at prevention is indicated. Am. J. Ind. Med. 35:302–309, 1999. © 1999 Wiley‐Liss, Inc.     

某有色金属企业1980～1999年职业伤害的流行病学研究

目的 掌握有色金属企业职业伤害分布特征，探索职业伤害发生规律和影响职业伤害发生的因素，为最大限度地控制和减少职业伤害提供科学依据。方法 用回顾性流行病学调查方法，调查某有色金属企业1980～1999年职业伤害发生情况和分布规律。结果 某有色金属企业1980～1999年发生职业伤害3831例。矿山3000例，工厂831例；男性3592例，女性239例；轻伤3630例，重伤104例，死亡57例。职业伤害在时间分布上有季节性特征。昼时分布有明显的集中趋势，高发于中班，圆形分布检验差异有显著性。人群分布以20～30岁年龄为高发人群，构成占40％以上，以20～25岁为最高点。工龄分布以1～10年工龄者为高发，最高点在1～5年工龄段。轻伤和重伤的年龄差别有统计学意义(Z=-2.184，P=0．029)，职业伤害程度与年龄呈正相关(r=0．041，P=0.011)。职业伤害主要分布在打眼、出矿、钳工、起重、支柱五大工种，易受伤部位是手、脚、头、四肢、五官，易受伤类型是物击、车辆、高坠。结论 某有色金属企业职业伤害发生率逐年下降，综合干预收到了效果，职业伤害是可以预防和控制的。     

An updated mortality study of workers at a petroleum refinery in Beaumont,Texas

The mortality experience of 7,119 workers who were employed at a Beaumont, Texas, refinery for at least 1 year between 1945 and 1987 was investigated. Mortality analyses based on standardized mortality ratios (SMRs) and 95% confidence intervals (95%CI) showed overall mortality was significantly lower than expected compared with the U.S. general population (SMR <=;=> 82, 95%CI = 79–86). Total cancer mortality was also lower than expected (SMR = 92, 95% CI = 84–100). Significant mortality deficits from several malignant and nonmalignant diseases were reported. A significant mortality increase in the broad category of lymphatic and hematopoietic cancers was found (SMR = 133, 95%CI = 103–170). This increase was attributed to a nonsignificant elevation in leukemia of all cell types combined (SMR = 139, 95%CI = 92–201) and a borderline significant increase in other lymphatic tissue cancer (SMR = 158, 95%CI = 101–235). The elevation in leukemia was confined to workers hired before 1950. Furthermore, the leukemia excess was shown to have peaked during the 1960s, with mortality no longer elevated post-1980. Analyses of cell type-specific leukemias showed a similar temporal pattern for acute myeloid leukemia (AML) which was not significantly elevated (SMR = 136, 95%CI = 59–268). Mortality from other leukemia cell types was similar to or lower than expected. Mortality from non-Hodgkin's lymphoma (NHL) (SMR = 140, 95%CI = 88–211) and multiple myeloma (MM) (SMR = 121, 95%CI = 55–230) were increased, but neither was statistically significant nor likely to be related to refinery employment. No death from asbestosis was reported, and mortality from mesothelioma and pulmonary fibrosis was lower than expected. Lung cancer mortality for the overall cohort was similar to expected. For the overall cohort, analyses by duration of employment and time since first employment showed no evidence of any trends for increasing cause-specific mortality. Separate analyses of male workers employed in operator jobs showed mortality patterns that were more favorable than those of the total cohort. Maintenance craftworkers showed statistically significant elevations in mortality for prostate cancer (SMR = 145, 95%CI = 107–194), leukemia (SMR = 179, 95%CI = 111–273), and other lymphatic tissue cancer (SMR = 233, 95%CI = 138–368). Detailed analyses indicated that, among maintenance craftworkers, mortality was elevated for AML, NHL, and MM, but none was significant. Furthermore, no upward trend by duration of maintenance jobs was observed. A small increase of lung cancer was observed among maintenance craftworkers (SMR = 120, 95%CI = 99–145), which was borderline significant. No relationship between lung cancer and duration of maintenance employment was found. In contrast, a deficit of pulmonary fibrosis was reported among maintenance craftworkers (SMR = 62, 95%CI = 17–159). These findings are discussed in conjunction with results from other refinery studies, and the limitations of the study are discussed. Am. J. Ind. Med. 33:61–81, 1998. © 1998 Wiley-Liss, Inc.     

Mortality patterns among petroleum refinery and chemical plant workers

A historical cohort study was conducted to evaluate the mortality experience of 6,831 employees of the Shell Oil Company, Deer Park, Texas, petroleum refinery and chemical plant with emphasis on cancer mortality. Subjects were all workers with potential plant exposure who were employed for at least 3 months during 1948-72. Vital status was determined as of 12/31/83 for 98% of the cohort and death certificates were obtained for 95.4% of 1,180 observed deaths. The statistical analyses excluded 159 female study members. For all causes of death combined, all cancers combined, and for most of the nonmalignant disease categories examined, there were deficits in mortality among refinery workers, chemical plant workers, and workers with experience in both areas. These deficits were generally most pronounced for chemical plant workers. An analysis of specific cancer sites revealed patterns of increased risk suggestive of a possible relationship between occupational exposures in the refinery and lympho-reticulosarcoma. Patterns of increased risk were also observed among chemical plant workers for a category of lymphopoietic tissue cancers, including multiple myeloma, myelofibrosis, polycythemia vera, and certain non-Hodgkin's lymphomas. Some very limited evidence of a possible workplace association was also found among refinery workers for leukemia and cancers of the central nervous system and biliary passages/liver. No evidence was found of an increased risk for cancer of the respiratory system or stomach or for malignant melanoma. A work history review of all suspect cancer excesses failed to identify any common work areas, job assignments, or exposure potentials, although the lack of detailed data on specific chemical exposures precluded accurate assessments of exposure-response.     

Cancer mortality among French Atomic Energy Commission workers

BACKGROUND: All causes and cancer mortality of 58,320 workers employed at the Commissariat à l'Energie Atomique (CEA) between 1946 and 1994 were compared with that of the general population in a retrospective cohort study. METHODS: Standardized Mortality Ratios (SMR) were computed with reference to the French national population. RESULTS: Between 1968 and 1994, 4,809 deaths occurred. A healthy worker effect is observed for men (SMR = 0.57, CI(90%) = [0.56;0.59]) and for women (SMR = 0.72, CI(90%) = [0.67;0.77]). Nine sites of cancer death were found to be in statistically significant deficit among men, none among women. An excess of pleural cancers is observed among men (SMR = 1.79, CI(90%) = [1.27;2.45]) and of malignant melanoma (SMR = 1.50, CI(90%) = [1.04;2.11]). An excess of breast cancer is observed among women on the borderline of significance (SMR = 1.14, CI(90%) = [0.94;1.37]). CONCLUSIONS: Excesses observed will have to be related to occupational exposures in the on-going cohort study on French nuclear workers which includes a retrospective exposures assessment.     

职业紧张对石油作业工人工作能力影响的因素分析

为了研究职业紧张与工作能力的关系及其影响因素 ,抽取 12 2个不同工种石油作业工人 12 30人 ,填写职业紧张调查问卷表和工作能力指数问卷表。结果表明 ,不同性别石油工人的工作能力差异有显著性(P <0 0 0 0 1) ,女性工作能力指数显著高于男性。随年龄、工龄的增长工作能力逐渐降低。石油工人工作能力随紧张强度的增加而降低。紧张强度越高工作能力越差 (P <0 0 0 1)。工作负荷和工作环境中的各种生产性有害因素与工作能力呈负相关。提示职业紧张可降低工人的工作能力 ,不良的工作环境因素、过重的工作负荷是影响工作能力的重要因素。     

Mortality among female employees of a chemical company

There have been few mortality studies conducted on working women despite their increasing presence in the work environment. This paper presents the findings of a cohort mortality study of 10,839 female employees with three or more days of service between 1940 and 1982 at the Midland or Bay City, Michigan, locations of the Dow Chemical Company. The cohort included substantial numbers of production and research personnel but was primarily comprised of clerical and office workers. Vital status was ascertained through 1982 for 89.4 percent of the cohort members, and death certificates were obtained for 94.0 percent of the 467 decedents. Comparisons of observed mortality with expected levels based on mortality rates for the U.S., Michigan, and a local 7-county area revealed consistently lower mortality in the cohort from the major causes of death, indicating a strong "healthy worker effect." Mortality from cancer of the cervix was significantly below expected levels, especially among women who were hired before 25 years of age. This observation, when combined with a nonsignificant excess of breast cancer, suggests a different distribution of maritally and sexually related risk factors between working and general populations of women. This and other findings are discussed relative to methodologic problems likely to accompany studies of working women.     

Injuries among domestic waste collectors

Detailed information on occupational injuries and the precise number of injuries among waste collectors is missing. In this study, risk circumstances associated with injuries among waste collectors were analyzed and described. The study was carried out in a single company with 667 employees in 1993. For each injury, information was collected on date, time, type, and severity of the injury, injury circumstances, department of employment, external or internal registration, sex, year of birth and employment, type of employment, and a registration of where the injury happened. A total of 17% of the employees experienced injury. The number of injuries decreased with increasing seniority and age. Most injuries occurred outside the company area. More injuries occurred on Mondays and Thursdays, and there were peaks in the injury rate in May and September. Most often injured was the back, followed by the knees, hands, and feet. The job as a waste collector was associated with a high risk of experiencing an occupational injury and the number of injuries decreased with increasing seniority and nonsignificantly with increasing age. Moreover, a seasonal and weekly variation was observed. Am. J. Ind. Med. 33:182–189, 1998. © 1998 Wiley-Liss, Inc.     

Lung cancer mortality in stainless steel and mild steel welders: A nested case-referent study

The association between welding and lung cancer has been studied in a nested case-referent study within a cohort of 8,372 metal workers. Lifetime exposure data on welding and other occupational exposures, as well as alcohol and smoking habits, were obtained by interviews of spouses and colleagues. Analysis was based on 439 deceased referents and 94 deceased cases. There was 70% excess of lung cancer associated with “welding exposure ever” (OR ± 95% C.I.: 1.68, 1.02–2.78). Overall OR “mild steel (MS) welding ever” was 1.64, 0.99-2.72. The risk estimates for welding exposures showed an increasing tendency up to 15 years of exposure. The pattern of stainless steel (SS) welding resembles that of mild steel with an estimated OR of 1.65, 0.88–3.0. The general conclusion is that MS welding as well as SS welding seems to be associated with an increased risk of lung cancer. Further followup of the cohort will enhance precision of the estimates. © 1996 Wiley-Liss, Inc.