Neuroendocrine effects of inhaling emissions generated by 3-dimensional (3D)-printing with polycarbonate stock

Inhalation of emissions from dimensional (3D) printing with polycarbonate feedstock generated particulate and volatile chemicals as well as respirable bisphenol A (BPA). BPA is a known endocrine disruptor that affects both reproductive and metabolic endocrine functions. The goal of this study was to determine whether exposure to emissions generated by 3D-printing with PC stock disrupted endocrine function in a male Sprague Dawley rat model. In the current study, inhalation of 3D emissions (3DE) at an average 2.5 mg/m³/day increased circulating estradiol levels after 15 and 30 days' exposure, and elevated testosterone levels after 15 days 3DE exposure. Changes also occurred in circulating concentrations of the anterior pituitary hormone and thyroid stimulating hormone (TSH) following 30 days' exposure to 3DE. These alterations in circulating steroid hormones were associated with changes in gonadotropin and thyroid stimulating hormone (Tsh) transcript levels in pituitary and estradiol receptor as well as in transcripts for inflammatory factors in olfactory bulb and gonadotropin releasing hormone transcript levels in the hypothalamus. Data are in agreement with studies demonstrating that exposure to BPA results in endocrine disruption. These findings are also consistent with the hypothesis that inhalation of 3DE may constitute another route of exposure that needs to be considered taking into account the endocrine disrupting effects generated by inhalation of 3DE.