Multiple Myeloma and Benzene Exposure in a Multinational Cohort of More Than 250,000 Petroleum Workers

doi:10.1006/rtph.1997.1162

Regulatory Toxicology and Pharmacology

Volume 26, Issue 2, October 1997, Pages 188-199

https://doi.org/10.1006/rtph.1997.1162 Get rights and content

Abstract

Case reports have suggested an association between benzene exposure and multiple myeloma. Because petroleum workers are exposed to benzene or benzene-containing liquids, studies of these workers provide an opportunity for investigating the relationship between benzene and multiple myeloma. A large number of cohort studies of petroleum workers have been conducted. However, few of them have reported results of multiple myeloma separately. One reason is that multiple myeloma is usually grouped with other lymphopoietic cancers in the analysis. Another reason is that multiple myeloma is relatively rare, and few individual studies are large enough to provide reliable risk estimates. To determine the risk of multiple myeloma in petroleum (refinery, distribution, production, and pipeline) workers, we have identified 22 cohort mortality studies of petroleum workers in the United States, the United Kingdom, Canada, and Australia. Authors of these studies were contacted, and data on the number of observed deaths and age-specific person-years of observation were requested. Data from individual studies were combined in a pooled analysis (meta-analysis). In addition to the pooled analyses, results for individual cohorts, most of which have never been reported before, are also presented. The combined multinational cohort consisted of more than 250,000 petroleum workers, and the observation period covered an interval of 55 years from 1937 to 1991. A total of 205 deaths from multiple myeloma were observed, compared to 220.93 expected, a total derived from respective national mortality rates. The corresponding standardized mortality ratio (SMR) was 0.93 and the 95% confidence interval (95% CI) was 0.81–1.07. Additional analyses were performed by type of facility and industrial process. Stratum-specific SMRs (95% CIs) were 0.92 (0.77–1.09) for refinery workers and 0.93 (0.69–1.23) for distribution workers. When individual cohorts were stratified by length of observation, no pattern was detected. The pooled analysis indicates that petroleum workers are not at an increased risk of multiple myeloma as a result of their exposure to benzene, benzene-containing liquids, or other petroleum products in their work environment. This conclusion is supported by cohort studies of workers in other industries who were exposed to benzene as well as by population-based case–control studies of multiple myeloma and occupational exposures.

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Regular ArticleMultiple Myeloma and Benzene Exposure in a Multinational Cohort of More Than 250,000 Petroleum Workers☆

Abstract

Regul. Toxicol. Pharmacol.

Clinical observations showing the role of some factors in the etiology of multiple myeloma

Acta Haematol.

Mortality study of cancer risk among oil refinery workers

Int. Arch. Occup. Environ. Health

Epidemiology of multiple myeloma and related plasma cell disorders

Progress in Myeloma, Biology of Myeloma

A case–control study of multiple myeloma nested in the American cancer society prospective study

Int. J. Cancer

An update of mortality among chemical workers exposed to benzene

Br. J. Ind. Med.

An updated cohort mortality study of workers at a northeastern United States petroleum refinery

Int. Arch. Occup. Environ. Health

Multiple myeloma—a case-control study

Br. J. Ind. Med.

An updated cause-specific mortality study of petroleum refinery workers

Br. J. Ind. Med.

Mortality among chemical workers exposed to benzene and other agents

Environ Res.

Texaco mortality study. I. Mortality among white male refinery, petrochemical, and research worker

J. Occup. Med.

Texaco mortality study. II. Patterns of mortality among white males by specific job groups

Am. J. Ind. Med.

Texaco mortality study. III. A cohort study of producing and pipeline workers

Am. J. Ind. Med.

Not uniformly true for each cause of death

J. Occup. Med.

Occupational and other environmental factors and multiple myeloma: A population based case–control study

Br. J. Ind. Med.

Multiple myeloma and engine exhausts, fresh wood, and creosote: A case-referent study

Am. J. Ind. Med.

Epidemiologic study of refinery and chemical plant workers

J. Occup. Med.

A retrospective mortality study of workers in three major U.S. refineries and chemical plants. Part 1. Comparisons with U.S. population

J. Occup. Med.

A retrospective mortality study of worker in three major U.S. refineries and chemical plants. Part II. Internal comparisons by geographic site, occupation, and smoking history

J. Occup. Med.

Occupational risk factors for multiple myeloma among Danish men

Cancer Causes Control

Multiple myeloma

Essential Haematology

An updated study of mortality among workers at a petroleum manufacturing plant

J. Occup. Environ. Med.

A case–control study of multiple myeloma in whites: Chronic antigenic stimulation, occupation, and drug use

Cancer Res.

Risk of cancer and exposure to gasoline vapors

Am. J. Epidemiol.

Mortality patterns among petroleum refinery and chemical plant workers

Am. J. Ind. Med.

Excess leukemia in a refinery population

J. Occup. Med.

Observations on the healthy worker effect

J. Occup. Med.

Occupational Epidemiology

Toxic substance exposure and multiple myeloma: A case–control study

J. Natl. Cancer Inst.

Regular Article
Multiple Myeloma and Benzene Exposure in a Multinational Cohort of More Than 250,000 Petroleum Workers☆