Lung response to crystalline nanocellulose exposure in rats

Crystalline nanocellulose (CNC) is an emerging nanomaterial with multiple commercial and industrial applications. Occupational exposure to CNC during the production and/or use of products containing the nanomaterial potentially resulting in adverse health effects among workers is possible. Therefore, there is an immediate need to determine the toxicity potential of CNC. Rats were exposed to either air or CNC (20 mg/m^3, 6 hours/day, 5 days/week, 14 days) and lung toxicity was determined one day following termination of the exposures. Compared to the control rats, the CNC exposed rats exhibited moderate changes in lung histology. Lactate dehydrogenase activity and the number of phagocytes present in the bronchoalveolar lavage were higher in the CNC exposed rats, compared with the controls. Global gene expression profiling identified 531 genes whose expressions were significantly different (fold change >1.5 and FDR p <0.05) in the lungs of the CNC exposed rats, compared with the controls. In summary, the data demonstrated the induction of pulmonary toxicity and global gene expression changes in the lungs of the rats in response to inhalation exposure to CNC. Rats (n=6) were exposed by whole body inhalation to air or crystalline nanocellulose (20 mg/m3, 6 hours/day for 5 days/week for a total of 14 days of exposure). One day after the final exposure, lung tissue was collected, and Next Generation Sequencing was performed on the lungs of 6 rats per treatment group (air/crystalline nanocellulose).