Occupational exposure to graphene and silica nanoparticles. Part II: pilot study to identify a panel of sensitive biomarkers of genotoxic, oxidative and inflammatory effects on suitable biological matrices

Abstract

The available biomonitoring studies on workers producing/handling nanomaterials (NMs) focused on potential effects on respiratory, immune and cardio-vascular system. Aim of this study was to identify a panel of sensitive biomarkers and suitable biological matrices to evaluate particularly genotoxic and oxidative effects induced on workers unintentionally exposed to graphene or silica nanoparticles during the production process. These nanomaterials have been chosen for ‘NanoKey’ project, integrating the workplace exposure assessment (reported in part I) with the biomonitoring of exposed workers reported in the present work. Simultaneously to workplace exposure characterization, we monitored the workers using: Buccal Micronucleus Cytome (BMCyt) assay, fpg-comet test (lymphocytes), oxidized DNA bases 8-oxoGua, 8-oxoGuo and 8-oxodGuo measurements (urine), analysis of oxidative stress biomarkers in exhaled breath condensate (EBC), FENO measurement and cytokines release detection (serum). Since buccal cells are among the main targets of NM occupational exposure, particular attention was posed to the BMCyt assay that represents a noninvasive assay. This pilot study, performed on 12 workers vs.11 controls, demonstrates that BMCyt and fpg-comet assays are the most sensitive biomarkers of early, still reparable, genotoxic and oxidative effects. The findings suggest that these biomarkers could represent useful tools for the biomonitoring of workers exposed to nanoparticles, but they need to be confirmed on a high number of subjects. However, such biomarkers don’t discriminate the effects of NM from those due to other chemicals used in the NM production process. Therefore, they could be suitable for the biomonitoring of workers exposed to complex scenario, including nanoparticles exposure.

Keywords:

• Buccal micronucleus cytome assay
• FPG-comet assay
• Exhaled breath condensate (EBC)
• silica nanoparticles
• graphene

Acknowledgements

We thank Dr. Roberta Andreoli, Dr. Rossella Alinovi and Dr. Silvana Pinelli of Medicine and Surgery Department, University of Parma (Italy) for their contribute in the measurement of urinary oxidized DNA bases. We thank Dr. Mariada Malvindi (IIT) for information on SiO2 NP case study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The present study is part of the Project ‘Nano and Key enabling technologies within the innovation processes: risk and opportunities in occupational settings by prevention through design (NanoKey)’, funded by the Italian Workers’ Compensation Authority (INAIL) and coordinated in cooperation between the INAIL Department of Occupational and Environmental Medicine Epidemiology and Hygiene, and the Italian Institute of Technology (IIT). The findings and conclusions in this publication are those of the authors and do not necessarily represent the views of the employing organizations.