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J F Acquavella

Publications and source records attributed to J F Acquavella.

At least 37 records · Page 2Linked to original sources
PubMed1992

An updated mortality study of workers in three major United States refineries and chemical plants.

A historical cohort study of refinery and chemical plant workers, originally observed from 1970 to 1977, was updated to the end of 1982. This cohort included 25,321 active, retired, and terminated workers at the Exxon refineries and chemical plants in Baton Rouge, Louisiana; Baytown, Texas; and Bayway/Bayonne, New Jersey. An emphasis was placed on the cancers previously reported to be increased in at least one petrochemical worker population. The population included a high proportion of retirees, providing adequate work experience and latency to evaluate risks associated with employment. Vital status was determined for 98.3% of the population and death certificates were obtained for 99.9% of the decedents. Mortality for "all causes of death" (standardised mortality ratio (SMR) = 89, 95% confidence interval (95% CI) 87-91) and for "all cancers" (SMR = 94, 95% CI 89-100) were lower than expected based on state rates. History of cigarette smoking collected from individual medical records and summarised work histories were used for subgroup analyses. There was no indication that cancers of primary interest were increased; however, blue collar workers at one plant had raised rates of kidney cancer (SMR = 246, 95% CI 146-390), which may require further evaluation.

Adult↗
PubMed1991

An adenomatous polyp case-control study to assess occupational risk factors following a workplace colorectal cancer cluster.

To assess potential etiologic factors among a population of Texas polypropylene workers previously found to have an excess of colorectal cancer (concentrated among mechanical and process workers), the authors conducted an adenomatous polyp case-control study. Cases (n = 24) were workers found to have adenomatous polyps during a company-sponsored colorectal cancer screening program, while controls (n = 72) were workers found to be free of polyps. Exposure assessment utilized a thorough industrial hygiene and toxicologic review of operations in conjunction with work activity interviews of cases and controls to develop chemical-specific exposure scores weighted by time, exposure level, and frequency of exposure. Stratified analyses and logistic regression found that cases tended to have higher exposure to pre-extrusion polymer plus additives (odds ratio (OR) = 2.6, 90% confidence interval (CI) 1.1-6.3) and higher exposure to certain finishing additives (OR = 4.8, 90% CI 1.5-15.3). Analyses by job category or area of the plant did not indicate additional risk factors. The exposures identified in this study are discussed in light of the available toxicologic data on these and related compounds. The need for confirmatory experimental and epidemiologic studies is noted.

Case-Control Studies↗
PubMed1991

A cohort study among workers at a metal components manufacturing facility.

To follow-up on a proportional mortality study that showed significantly elevated proportional mortality ratios for lung cancer and a subgroup of nonmalignant respiratory diseases, we conducted a cohort mortality study (1950-1987) among 4627 employees of a metal components manufacturing facility. The findings of this study showed lower than expected mortality from all causes of death and all cancers. However, lung cancer mortality was significantly elevated (standardized mortality ratio = 131, 95% confidence interval (102-165), owing to elevated mortality among hourly workers (standardized mortality ratio = 153, 95% confidence interval 118-195). Hourly workers also showed a significantly elevated rate for the residual category "other nonmalignant respiratory disease" (standardized mortality ratio = 170, 95% confidence interval 110-251) and a significant deficit of leukemia (standardized mortality ratio = 16, 95% confidence interval 0-87). Analyses by duration of employment did not show significant trends for any cause of death. Smoking information was not available, but several indirect methods were used to estimate the potential confounding effect of smoking.

Cause of Death↗
PubMed1991

Improving the conduct of epidemiologic studies: an introduction to quality principles.

The process of conducting and ensuring the quality of epidemiologic studies has received little attention in the published literature. In concert with the variable nature of observational research, this has created a perceived need for guidelines relating to the conduct and reporting of epidemiologic studies. Amendments to two recent government regulations stipulate that epidemiologic studies should be carried out in accordance with as yet unspecified guidelines. Yet, guidelines alone will not improve the quality of epidemiologic studies. A more comprehensive approach is envisioned with reference to specific quality improvement principles used in industry.

Epidemiologic Methods↗
PubMed1990

Reasons for participation and nonparticipation in a colorectal cancer screening program for a cohort of high risk polypropylene workers.

Little is known about reasons for participation in occupational colorectal cancer screening programs using flexible sigmoidoscopy and barium enema. To assess this issue, telephone interviews were conducted with a sample of participants and nonparticipants in such a program. This study was a follow-up of a previous assessment of factors that affected screening participation among a cohort found to have elevated rates of colorectal cancer. The major finding of this survey was that the absence of symptoms was the major reason for nonparticipation, although both participants and nonparticipants expressed the view that early detection was important and that colorectal cancer could be cured if treated at an early stage. Based on the results of this study and of other surveys, educational messages to workers explaining the asymptomatic development of colorectal cancer should be tried as a way of increasing participation.

Aged↗
PubMed1990

Future directions in epidemiologic studies of 1,3-butadiene-exposed workers.

To date, epidemiologic research on 1,3-butadiene has consisted of cohort mortality studies of workers in the styrene-butadiene rubber (SBR) and butadiene monomer industries. These studies have been extremely useful both in defining the focus on human health effects to the lymphopoietic cancers and in providing a perspective on which to evaluate the available animal models for human risk assessment. The next step for epidemiologic research will involve a lymphopoietic cancer case control approach to enable a more precise assessment of whether there is a relationship between 1,3-butadiene exposure and lymphopoietic cancer. In addition, periodic mortality updates of the 1,3-butadiene-exposed worker cohorts will be important to monitor trends in lymphopoietic cancer rates and to ensure that other cancers with long latency do not begin to show elevated rates. This paper describes an industry-sponsored program of case-control and cohort mortality update studies along with the critical elements in research design and analysis for each study. Epidemiological studies will play an important role in testing hypotheses developed from toxicological studies about potential biological mechanisms of 1,3-butadiene carcinogenesis in humans.

Animals↗
PubMed1990

Assessment of colorectal cancer incidence among polypropylene pilot plant employees.

Our recent study reported a colorectal cancer excess among workers involved in the manufacture of polypropylene. To follow up on this finding, we initiated a study of colorectal cancer incidence among polypropylene pilot plant workers within the same company. The purpose of this investigation was to determine whether colorectal cancer incidence was elevated among workers who may have had exposures similar to those experienced on the commercial production unit. The study population included 183 employees who worked at least 6 months on either of two pilot plants. Overall, there were three observed colorectal cases v. 3.3 expected (standardized incidence ratio = 0.9, 90% confidence interval 0.3 to 2.3). Analyses for the process, mechanic, and laboratory subgroup showed rates consistent with expected values (3 observed, 2.8 expected; standardized incidence ratio = 1.1, 90% confidence interval 0.3 to 2.8). Analyses by duration of employment and latency did not show patterns consistent with the colorectal cancer excess previously reported. The likelihood of lower or different exposures on the pilot plant than would be found on commercial production units is discussed along with the need for studies of workers in other polypropylene manufacturing environments.

Chemical Industry↗
PubMed1989

Assessment of colorectal cancer screening outcomes among workers involved in polypropylene manufacture.

To follow up on a previous finding of an elevated colorectal cancer incidence rate among Exxon employees on a unit devoted to the manufacture of polypropylene (the polyolefin unit [POU]), a company-sponsored screening program was offered to all former and present POU workers. Overall participation was 52.5%, with lower participation among older workers and workers who had retired or were no longer employed by the company. Evaluation of polyp prevalence rates for POU workers v rates for non-Exxon employees screened at the same clinic showed a general pattern of elevated rates for POU employees, especially for mechanical and process workers. This pattern was most marked for polyps at least 0.5 cm in diameter, but findings were less clear for adenomatous polyps. The effect of factors that might bias evaluation of colorectal polyp prevalence rates (eg, selection bias, observation bias, genetic susceptibility) is discussed, but none of these factors seemed a likely explanation for the findings observed in this study.

Adult↗
PubMed1989

Factors associated with participation in an occupational program for colorectal cancer screening.

This study reports factors associated with participation in a colorectal cancer screening program for a cohort of workers on a polypropylene manufacturing unit. The impetus for the screening program was the discovery of a colorectal cancer cluster among workers on this unit. The program included a life-style/risk factor questionnaire, fecal occult blood test, a 60-cm colonoscopy, and an air-contrast barium enema. Overall, 52.5% of the 406 men who were offered screening participated in the program. Of those screened, only 40% attended a briefing, but over 80% of those who attended a briefing came for screening. Factors associated with completion of screening are analyzed and discussed in the context of the literature on participation in colorectal screening programs. The implications for colorectal cancer screening of occupational groups believed to be at high risk are considered.

Adult↗
PubMed1988

Evaluation of excess colorectal cancer incidence among workers involved in the manufacture of polypropylene.

In response to reports of an unusually high number of colorectal cancers among employees on a unit devoted to the manufacture of polypropylene, we examined colorectal cancer incidence rates for 335 workers with at least 6 months employment on this unit from 1960 to 1985. Assuming a 10-year latent period, we found a significant 5.6-fold colorectal cancer excess (7 observed/1.26 expected, standardized incidence ratio (SIR) = 5.6, 95% confidence interval (CI) 2.2 to 11.5), concentrated among mechanical (5 observed/0.47 expected, SIR = 10.6, 95% CI 3.4 to 24.7) and process workers (2 observed/0.40 expected, SIR = 5.0, 95% CI 0.6 to 17.8). No colorectal cancer was found among administrative/office personnel on our study roster. All of the cancers occurred in employees who initially worked on the unit during its first 6 years of operation, and the minimum interval from start of employment to cancer development was 20 years. In addition, the ages of the cancer cases suggested a younger age distribution than would be expected based on general population rates. Since this study was descriptive in nature, we could not evaluate whether the cancer excess was related to occupational exposures, other environmental factors, or the random clustering of cancers in our worker populations (viz, "chance"). Further studies are currently ongoing to assess occupational and/or personal factors that may be related to this colorectal cancer excess.

Adenocarcinoma↗
PubMed1987

Mortality among plutonium and other radiation workers at a plutonium weapons facility.

Mortality among 5,413 white males who were employed for at least two years at a plutonium weapons facility was investigated to measure risks from exposures to low levels of plutonium and external radiation. When compared with US death rates, fewer deaths than expected were found for all causes of death, all cancers, and lung cancer. No bone cancer was observed. An excess of brain tumors was found for the cohort in general. Elevated rate ratios for all causes of death and all lymphopoietic neoplasms were found when employees with plutonium body burdens greater than or equal to 2 nCi were compared with those with body burdens less than 2 nCi, while accounting for age, calendar period, and induction time. Increased rate ratios were also found for esophageal, stomach, colon, and prostate cancers, and for lymphosarcomas and reticulum cell sarcomas. No elevated rate ratios were noted for bone and liver cancers. When employees with cumulative exposures greater than or equal to 1 rem were compared with those with exposures less than 1 rem, elevated rate ratios were found for myeloid leukemia, lymphosarcoma and reticulum cell sarcoma, liver neoplasms, and unspecified brain tumors. No overall dose-response relationships were found for plutonium or external radiation exposures. Standardized rate ratios increased, however, as plutonium body burden levels increased for all causes, all cancers, and digestive cancers at five years induction time. Standardized rate ratios also increased as external radiation exposure categories increased for all lymphopoietic cancers and unspecified brain tumors for a two-year induction period. With the exception of analyses of combined categories of death, and perhaps of lung cancer, confidence limits were wide, indicating limited precision. Nevertheless, these findings suggest that increased risks for several types of cancers cannot be ruled out at this time for individuals with plutonium body burdens of greater than or equal to 2 nCi. Plutonium-burdened individuals should continue to be studied in future years.

Air Pollutants, Radioactive↗
PubMed1986

An analysis of mortality follow-up through the National Death Index for a cohort of refinery and petrochemical workers.

Along with our submission to the National Death Index (NDI) of a cohort of more than 23,000 petrochemical and refinery workers, we included 1,449 known U.S. deaths to determine the completeness of death ascertainment through the NDI. A number of factors that may affect follow-up were examined including sex, race, age and reporting area. Overall, NDI detected 97.1% of known deaths. Follow-up was slightly better for males (97.2%) than for females (92.0%) and was significantly better for whites (97.6%) than for nonwhites (92.0%). Analyses by reporting area showed very complete follow-up from all locations (93.4%-100%) except for the New York City area (71.4%). These findings indicate that NDI is an extremely useful source for vital status follow-up, though follow-up may be somewhat less complete for certain subgroups of an occupational study cohort.

Adult↗
PubMed1986

Assessment of clinical, metabolic, dietary, and occupational correlations with serum polychlorinated biphenyl levels among employees at an electrical capacitor manufacturing plant.

In order to assess the extent of polychlorinated biphenyl (PCB) exposure and potential health effects, a clinical-epidemiologic survey was initiated among 205 workers at a capacitor manufacturing plant. The geometric mean serum PCB level for workers was 18.2 ppb (SD 2.88), with a range of 0 to 424 ppb. Multiple regression analysis found duration of employment, cumulative occupational exposure, cumulative fish consumption, and cholesterol level to be significant predictors of log serum PCB levels. Of these predictors, duration of employment and cumulative occupational exposure were the strongest contributors to the regression model, indicating the dual importance of opportunity for dermal contact and respiratory exposure level in contributing to workers' serum PCB levels.

Diet↗