Leukemia Risk Associated With Low-Level Benzene Exposure

Jones

Cancer Epidemiology, Biomarkers &Amp; Prevention

2007

116

Exposure to benzene, an important industrial chemical and component of gasoline, is a widely recognized cause of leukemia, but its association with non-Hodgkin lymphoma (NHL) is less clear. To clarify this issue, we undertook a systematic review of all case-control and cohort studies that identified probable occupational exposures to benzene and NHL morbidity or mortality. We identified 43 case-control studies of NHL outcomes that recognized persons with probable occupational exposure to benzene. Forty of these 43 (93%) studies show some elevation of NHL risk, with 23 of 43 (53%) studies finding statistically significant associations between NHL risk and probable benzene exposure. We also identified 26 studies of petroleum refinery workers reporting morbidity or mortality for lymphomas and all neoplasms and found that in 23 (88%), the rate of lymphoma morbidity or mortality was higher than that for all neoplasms. A substantial healthy-worker effect was evident in many of the studies and a comprehensive reevaluation of these studies with appropriate adjustments should be undertaken. Numerous studies have also reported associations between benzene exposure and the induction of lymphomas in mice. Further, because benzene is similar to alkylating drugs and radiation in producing leukemia, it is plausible that it might also produce lymphoma as they do and by similar mechanisms. Potential mechanisms include immunotoxicity and the induction of double-strand breaks with subsequent chromosome damage resulting in translocations and deletions. We conclude that, overall, the evidence supports an association between occupational benzene exposure and NHL. (Cancer Epidemiol Biomarkers Prev 2007;16(3):385 -91)

Section: Elevated Risks Of Chronic Lymphocytic Leukemiamentioning

confidence: 97%

Benzene Exposure and Risk of Non-Hodgkin Lymphoma

Jones

Cancer Epidemiology, Biomarkers &Amp; Prevention

2007

116

“…Accordingly, it has been classified by the international agency for research on cancer (IRAC) (1982). There is an agreement that benzene can affect the hematopoietic system (10). It seems that all humans may be exposed to benzene.…”

Section: Introductionmentioning

confidence: 99%

Hematologic Evaluation of Painting Hall Workers in an Automobile Manufacturing Company

et al. 2017

Background: Exposure to benzene causes several adverse effects, including decreased number of erythrocytes, leucocytes, and red blood cells, and results in aplastic anemia. The aim of this study was to investigate hematological changes due to benzene exposure in painting workers. Methods: This study was conducted on benzene-exposed and nonexposed workers in Tehran, Iran. The study sample included 40 painters exposed to different levels of benzene and 40 unexposed controls in an automobile manufacturing company. Sampling was carried out with an active pump sampler, using the NIOSH method 1501. Varian C-3800 gas chromatography-flame ionization detector (GC-FID) was used for the analysis of 40 benzene samples. Blood samples from 80 workers were collected from both the case and control groups. Hematological indices were analyzed for red blood cell, white blood cell, hematocrit, hemoglobin, platelet, and white cell differential count.

Int Arch Occup Environ Health

“…Their results (Glass et al 2003;Table 4) showed that the four exposure groups between 1 and 16 ppm-years, compared to a baseline group with exposures up to 1 ppm-year, had odds ratios of 3.9, 6.1, 2.4 and 5.9. The two highest of these were declared statistically signiWcant at 5%, although there was no obvious trend with exposure.…”

Section: Resultsmentioning

confidence: 99%

“…More detailed nested case-control studies have attempted to address the question of risks of benzene at a greater level of detail, focussing on lymphatic-haematopoietic cancers as an outcome. Principal among these have been the studies of workers from the petroleum marketing and distribution workers from Canada , UK (Rushton and Romaniuk 1997), USA (Wong et al 1999) and Australia (Glass et al 2003). The results from the Wrst three studies were broadly similar in showing little evidence of an eVect of low benzene exposure.…”

Section: Introductionmentioning

confidence: 99%

A review of the data quality and comparability of case–control studies of low-level exposure to benzene in the petroleum industry

Miller

Fransman

Heederik

et al. 2009

Purpose Published case-control studies of risks of leukaemia following low exposures to benzene in the distribution of petroleum (gasoline) have not all identiWed the same level of risk, but the studies have had diVerences in cohort inclusion, case determination and availability of occupational and lifestyle data. We reviewed the quality and comparability of the data from three (of four) studies. Methods Through site visits, discussions with the investigators and reading study reports, we reviewed and audited the methods used for selecting cases and controls, for estimating individual exposures and for analysing and interpreting the data. Case-control comparisons of exposures were examined using customised graphs. Results We found that• there were no issues of subject selection, methods or general data quality that were likely to have distorted their internal comparisons;• we could not check in detail whether the metric for exposure assessments was the same across the studies;• the exposure assessments for the Australian study required the least backward estimation, and the Canadian, which also had fewest cases, the most;• evidence of an increased risk at higher exposures in Australia was convincing. ConclusionsThe Wndings are consistent with some eVect of benzene at higher lifetime exposures. A proposed pooled analysis should improve quantiWcation of any exposureresponse relationship.