MACRAMÉ Partner Spotlight: BAuA

BAuA is the German Federal Institute for Occupational Safety and Health. It is a federal departmental research institution dedicated to safety and health at work and human-centred work design. At its three locations in Dortmund, Berlin, and Dresden, nearly 800 staff members work at the intersection between science, policymaking, and practice. They conduct research and development projects, provide policy advice, perform statutory and official functions, and transfer knowledge into workplace practice. BAuA is a key player in the development of OECD Test Guidelines for nanomaterials and (other) advanced materials, as it co-chairs the Malta Initiative and coordinated the EU-funded coordination and support action project NanoHarmony.

The unit 4.I.5 Materials and Particulate Hazardous Substances investigates and evaluates occupational safety aspects of activities involving particulate hazardous substances such as nanomaterials and (other) advanced materials. The unit operates state-of-the-art equipment for aerosol measurement, particle analysis and correlative imaging methods to answer current questions relevant to occupational safety and health on particulate hazardous substances and advanced materials.

BAuA’s role in the MACRAMÉ Project

BAuA coordinates MACRAMÉ´s activities towards standardisation and harmonisation of method developments and is leading work package 5. Within this work package, BAuA organises together with LNE, BioMS, RIVM, Temasol, LIST and other MACRAMÉ partners the annual Harmonisation and Standardisation Workshop as well as webinars on topics like standardisation, validation and AOPs. The 1^st MACRAMÉ Regulatory Risk Assessors Summit held at BAuA in Berlin (27^th – 28^th of November 2023) and organised by BAuA and BioMS in collaboration with other MACRAMÉ partners, marked a pivotal event in highlighting challenges, needs, and gaps in the regulatory frameworks important for the risk assessment during the life cycle of advanced materials and advanced materials-containing products (see Figure 1).

^{Figure 1. Impressions from the 1st Regulatory Risk Assessors Summit held at BAuA with experts from various fields participating and discussing challenges and needs for the regulatory risk assessment during the life cycle of advanced materials.}

Using and expanding the expertise in correlative microscopy, BAuA is investigating MACRAMÉ samples with scanning electron microscopy, light microscopy and Raman spectroscopy combined with by BAuA developed software solutions for image correlation and neural-network-integrated image and spectra analysis. The harmonisation of correlative microscopy experimental procedures is performed within MACRAMÉ in collaboration with IBE and EMPA. A key challenge for the identification of advanced materials is to discriminate between the carbon-based background (e.g. cells) and the graphene related materials that are also carbon-based. As highlight in Figure 2 below, Raman spectroscopy correlated with light microscopy enables the clear discrimination.

^{Figure 2. Correlative microscopy. A: Light microscopy image of a macrophage cell. B: Raman spectra cluster analysis of the same macrophage cell (the false colour code is indicating the following: blue=glass, light blue=cytoplasm, pink=nucleus, orange=graphene flakes). C: Correlative microscopy overlay of the light microscopy image and the Raman spectra cluster analysis.}

Furthermore, BAuA develops and harmonises methods for targeted aerosol generation, especially of fibrous materials and graphene related materials. In MACRAMÉ, aerosols are generated and used for in vitro experiments in close collaboration with IBE, LIST and RIVM.