Biomedical subjects

A H Okun

Publications and source records attributed to A H Okun.

4 recordsLinked to original sources

PubMed1993

Mortality of workers employed in shoe manufacturing.

A retrospective cohort mortality study was conducted among 7814 white shoe manufacturing workers followed from 1940 through 1982. The workers were potentially exposed to solvents (including toluene) and solvent-based adhesives. Benzene may have been present as an impurity of toluene. Mortality due to leukemia and aleukemia was not statistically significantly elevated. Statistically significant excess mortality due to cancer of the trachea, bronchus and lung was observed in the total cohort [standardized mortality ratio (SMR) 147, 95% confidence interval (95% CI) 120-180] and showed a statistically significant trend in standardized relative risk with increasing potential latency, but not with increasing duration of employment. Chronic nonmalignant respiratory disease was significantly elevated among the men (SMR 158, 95% CI 114-217) but was less than expected among the women (SMR 79), a finding suggesting a possible contribution of smoking to the mortality from respiratory cancer. However, adjustment for the potential effects of smoking did not completely eliminate the increased risk for lung cancer.

Adult↗

PubMed1991

Enhancing the quality of epidemiologic studies.

Three principles can improve epidemiologic studies (1) Conduct open scientific review of research protocols and final reports, (2) Disseminate study results to all appropriate parties, and (3) Incorporate new scientific methods into the research and utilize expertise from other disciplines. The procedures we describe are used within the Industrywide Studies Branch of the National Institute for Occupational Safety and Health to implement these principles.

Clinical Protocols↗

PubMed1987

Benzene and leukemia. An epidemiologic risk assessment.

To assess quantitatively the association between benzene exposure and leukemia, we examined the mortality rate of a cohort with occupational exposure to benzene. Cumulative exposure for each cohort member was estimated from historical air-sampling data and, when no sampling data existed, from interpolation on the basis of existing data. The overall standardized mortality ratio (a measure of relative risk multiplied by 100) for leukemia was 337 (95 percent confidence interval, 154 to 641), and that for multiple myeloma was 409 (95 percent confidence interval, 110 to 1047). With stratification according to levels of cumulative exposure, the standardized mortality ratios for leukemia increased from 109 to 322, 1186, and 6637 with increases in cumulative benzene exposure from less than 40 parts per million-years (ppm-years), to 40 to 199, 200 to 399, and 400 or more, respectively. A cumulative benzene exposure of 400 ppm-years is equivalent to a mean annual exposure of 10 ppm over a 40-year working lifetime; 10 ppm is the currently enforceable standard in the United States for occupational exposure to benzene. To examine the shape of the exposure-response relation, we performed a conditional logistic-regression analysis, in which 10 controls were matched to each cohort member with leukemia. From this model, it can be calculated that protection from benzene-induced leukemia would increase exponentially with any reduction in the permissible exposure limit.

Adult↗

PubMed1985

Mortality patterns among styrene-exposed boatbuilders.

In order to test the hypothesis that leukemia and lymphoma may be associated with exposure to styrene, cause-of-death patterns were studied at two reinforced plastic boatbuilding facilities. There were 5,021 workers who met the criterion of having worked at the two plants between 1959 and 1978. Based on industrial hygiene surveys conducted at the two plants, 2,060 individuals were determined to have worked in departments classified as having high exposure to styrene. There were 176 deaths observed among the total cohort, in comparison to 195.3 deaths expected (standardized mortality ratio [SMR] = 90). Among the high styrene exposure group, 47 deaths were observed in comparison to 41.5 deaths expected (SMR = 113). No leukemia or lymphoma deaths were observed in either the high exposure group or the total cohort. An excess of accidental deaths among the high exposure group (18 observed vs 12.4 expected) did not appear to be due to styrene's acute central nervous system effects, since none of the individuals were employed at the facilities at the time of their death. However, the possibility of a chronic effect could not be dismissed. While leukemia and lymphoma did not appear to be related to styrene exposure, the study had little statistical power to detect excesses of these diseases, due to the short length of observation and the young age of most cohort members. It was concluded that the cohort should provide increasingly useful information on chronic styrene toxicity as the population ages and the observation period increases.

Adolescent↗