INTEROCC case–control study: lack of association between glioma tumors and occupational exposure to selected combustion products, dusts and other chemical agents

Abstract

BackgroundThe aim was to investigate possible associations between glioma (an aggressive type of brain cancer) and occupational exposure to selected agents: combustion products (diesel and gasoline exhaust emissions, benzo(a)pyrene), dusts (animal dust, asbestos, crystalline silica, wood dust) and some other chemical agents (formaldehyde, oil mist, sulphur dioxide).MethodsThe INTEROCC study included cases diagnosed with glioma during 2000–2004 in sub-regions of seven countries. Population controls, selected from various sampling frames in different centers, were frequency or individually matched to cases by sex, age and center. Face-to-face interviews with the subject or a proxy respondent were conducted by trained interviewers. Detailed information was collected on socio-economic and lifestyle characteristics, medical history and work history. Occupational exposure to the 10 selected agents was assessed by a job exposure matrix (JEM) which provides estimates of the probability and level of exposure for different occupations. Using a 25% probability of exposure in a given occupation in the JEM as the threshold for considering a worker exposed, the lifetime prevalence of exposure varied from about 1% to about 15% for the different agents. Associations between glioma and each of the 10 agents were estimated by conditional logistic regression, and using three separate exposure indices: i) ever vs. never; ii) lifetime cumulative exposure; iii) total duration of exposure.ResultsThe study sample consisted of 1,800 glioma cases and 5,160 controls. Most odds ratio estimates were close to the null value. None of the ten agents displayed a significantly increased odds ratio nor any indication of dose–response relationships with cumulative exposure or with duration of exposure.ConclusionThus, there was no evidence that these exposures influence risk of glioma.

Association between δ-aminolevulinate dehydratase G177C polymorphism and blood lead levels in brain tumor patients

“…The present study observation of the increased risk with the ALAD2 variant for meningioma, but not for glioma or other types, parallels with the observation of Lacourt et al (27) who confirmed the lack of association between glioma tumors and occupational exposure to selected combustion products, dusts and other chemical agents. The only strongly established risk factors for glioma are rare (ionizing radiation and rare medical conditions), possibly rarer compared to the agents that were examined in the present study.…”

The INTEROCC case-control study: risk of meningioma and occupational exposure to selected combustion products, dusts and other chemical agents

“…The vast majority (98%) of occupational histories were obtained from face-to-face interview, with the remaining being obtained from proxy respondents. In a previous analysis from this study in relation to glioma for the same agents, we found no association between oil mists and glioma35; we might have expected to see some excess if there was preferential recall of jobs that involved exposure to oil mists among the cases. However, we have no reason to believe that recall of jobs associated with exposure to mineral oils would have been biased in any way.…”

Brain and Central Nervous System Tumors☆

“…None of the exposures selected showed any significant relationship to glioma with any of three different exposure indices, as reported in Lacourt et al (2013). Selected exposures included solvents, combustion products, metals, and dusts, as well as formaldehyde and sulphur dioxide.…”