Inhalation of polycarbonate emissions generated during 3D printing processes affects neuroendocrine function in male rats

ABSTRACT

Three-dimensional (3D) printing of manufactured goods has increased in the last 10 years. The increased use of this technology has resulted in questions regarding the influence of inhaling emissions generated during printing. The goal of this study was to determine if inhalation of particulate and/or toxic chemicals generated during printing with polycarbonate (PC) plastic affected the neuroendocrine system. Male rats were exposed to 3D-printer emissions (592 µg particulate/m³ air) or filtered air for 4 h/day (d), 4 days/week and total exposures lengths were 1, 4, 8, 15 or 30 days. The effects of these exposures on hormone concentrations, and markers of function and/or injury in the olfactory bulb, hypothalamus and testes were measured after 1, 8 and 30 days exposure. Thirty days of exposure to 3D printer emissions resulted in reductions in thyroid stimulating hormone, follicle stimulating hormone and prolactin. These changes were accompanied by (1) elevation in markers of cell injury; (2) reductions in active mitochondria in the olfactory bulb, diminished gonadotropin releasing hormone cells and fibers as well as less tyrosine hydroxylase immunolabeled fibers in the arcuate nucleus; and (3) decrease in spermatogonium. Polycarbonate plastics may contain bisphenol A, and the effects of exposure to these 3D printer-generated emissions on neuroendocrine function are similar to those noted following exposure to bisphenol A.

KEYWORDS:

• Inhalation
• 3D printing
• neuroendocrine
• males

Disclosure statement

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

Data availability statement

The data included in this manuscript can be found at Data and Statistics Gateway in the Research Data section: https://www.cdc.gov/niosh/data/researchdata.html

Disclaimer

The findings and conclusions in this manuscript are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention and the U.S. Consumer Safety Product Commission. This work has not been reviewed or approved by and does not necessarily represent the views of the U.S. Consumer Product Safety Commission. Certain commercial equipment, instruments, or materials are identified in this paper to specify the experimental procedure adequately. Such identification is not intended to imply recommendation or endorsement by the Consumer Product Safety Commission, nor is it intended to imply that the materials or equipment identified are necessarily the best available for the purpose.

Additional information

Funding

The work was supported by the U.S. Consumer Safety Product Commission [Interagency Agreement with CPSC 61320618H0019]; U.S Consumer Product Safety Commission [Interagency Agreement with CPSC 61320618H0019]; Government Interagency Agreement with CPSC [61320618H0019]; U.S. Consumer Product Safety Commission [Interagency Agreement with CPSC 61320618H0019].