Investigation of Chemical Composition and Fiber-Occurrence in Inhalable Particulate Matter Obtained from Dry Cutting Processes of Carbon Fiber Reinforced Concrete Composite, Concrete and the Carbon Fiber Reinforcement Materials

The most commonly used construction material nowadays is steel-reinforced concrete which underlies corrosion and thus buildings are susceptible for structural collapses. Recently, a new construction material resistant to oxidation and with a higher tensile strength called carbon concrete composite (C3) was developed. The new material allows resource-saving constructions using carbon fiber instead of steel reinforcement materials embedded in a concrete matrix. C3 reinforcements consist of carbon fibers coated with an organic polymer matrix. In this study, abrasive dust from a dry cutting process of two C3 reinforcement materials, as well as a C3 material were investigated with respect to the occurrence of toxic fibers or harmful organic compounds in the inhalable particulate matter (PM) fractions PM2.5 and PM10. It could be shown that the ratio between elemental and organic carbon in PM10 is dependent on the shape of the C3 reinforcement material due to different mechanisms of PM formation. This could have an impact on the toxicity of different C3 reinforcement materials. Harmful fibers according to the World Health Organization (WHO) definition like they are found in asbestos concrete were not found. However, bisphenol A (BPA) as well as the PAHs phenanthrene, anthracene, fluoranthene and pyrene were found due to pyrolysis of the organic matrix material at the edge of the sawblade differentiating the Carcinogenic Equivalency (TEQ) of investigated materials and their PM fractions. Furthermore, derivatives of BPA occurred in abrasive dust from C3 reinforcement materials potentially leading to genotoxicity and reproductive toxicity.