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Updated: May 22, 2026
12:15
Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter
Published on: May 29, 2019
Global DNA methylation and low-level exposure to benzene
Silvia Fustinoni1, Federica Rossella, Elisa Polledri
1Department of Occupational and Environmental Medicine, University of Milan and Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy. silvia.fustinoni@unimi.it
La Medicina Del Lavoro
|May 25, 2012
Summary
Benzene exposure, common in occupational settings, is linked to reduced global DNA methylation and repetitive element methylation in blood. These methylation changes appear to be independent responses to benzene exposure.
Area of Science:
- Environmental Health
- Epigenetics
- Toxicology
Background:
- Global genomic hypomethylation is a hallmark of cancer, particularly leukemia.
- Benzene, a known leukemogen, is suspected to induce hypomethylation, but its effect on global DNA methylation remains unclear.
Purpose of the Study:
- To investigate the association between benzene exposure and global genomic DNA methylation levels.
- To examine DNA methylation in repetitive elements (Alu and LINE-1) in response to benzene exposure.
Main Methods:
- Global DNA methylation and methylation at Alu/LINE-1 repetitive elements were measured in peripheral blood cells of 78 gasoline station attendants and 58 controls.
- Exposure was assessed via personal airborne benzene and urinary biomarkers (benzene, t,t-muconic acid, S-phenylmercapturic acid).
Main Results:
- A statistically significant decrease (1.6%) in global DNA methylation was observed in exposed participants compared to controls.
- Global DNA methylation and repetitive element methylation (Alu, LINE-1) were negatively correlated with airborne benzene levels.
- Global DNA methylation and repetitive element methylation were not correlated with each other, suggesting independent responses.
Conclusions:
- Benzene exposure is associated with significant alterations in both global DNA methylation and repetitive element methylation in blood.
- Global and repetitive element methylation likely represent independent epigenetic responses to benzene exposure.
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