The EU European Union (European Union )-funded HARMLESS project used the Early Awareness and Action System for Advanced Materials (Early4AdMa) to identify potential safety and sustainability issues of various inorganic aerogel mats. The approach required additional hazard data and exposure scenarios to be fully useful for ranking the different types of materials. Nevertheless, considering safety and sustainability aspects early in the product development process is valuable to stimulate safe and economically viable innovation with advanced materials.

Screening for safety and sustainability issues: A case study on insulating aerogel mats

The EU has the ambition to develop advanced materials that are safe, sustainable, and circular. Inorganic aerogel mats are an example of products currently being developed using advanced materials. These mats have high insulating properties due to nanostructures of their internal pores. Their external dimensions, however, are larger. Consequently, these novel nano-enabled products are not regulated as nanomaterials under REACH. Little is known about their safety and sustainability. The EU-funded HARMLESS project used these mats as a case study to discover potential safety and sustainability issues at an early Technology Readiness Level (TRL). For this purpose, they applied the Early Awareness and Action System for Advanced Materials (Early4AdMa).

What is Early4AdMa?

Early4AdMa is an approach that aims to identify and describe potential safety, sustainability and regulatory issues of advanced materials early in their development or use. This tiered approach was initially developed(PDF) by RIVM, BfR, BAuA and UBA and was further developed by the OECD. Tier 1 of Early4AdMa is a simple screening assessment based on the NESSI score (Novelty, Exposure, Severity, Scope, Immediacy), followed by considerations on the applicability of existing regulation and sustainability aspects. If the material scores high, it moves to Tier 2 for a more detailed assessment of the warnings from Tier 1.

The value of Early4AdMa

During an expert workshop with the OECD WPMN Advanced Materials Steering Group, the Early4AdMa approach was used to screen the safety and sustainability aspects of four different inorganic aerogel mats and two mats consisting of conventional mineral wools. The approach proved helpful for regulators to pinpoint knowledge gaps in these areas. However, innovators found the information requirements too demanding for products in the early stages of development. Despite the relatively high TRL level of the aerogel materials (level >8, launched on market), the experts identified that many of the Tier 2 questions in Early4AdMa are not suitable, mainly due to a lack of data on exposure and hazard.

Combining Early4AdMa and JRC’s SSbD framework

The HARMLESS researchers then combined Early4AdMa’s approach with the draft Safe and Sustainable by Design (SSbD) framework that the EC Joint Research Center (JRC) developed. This framework provides guidance for assessing the safety and sustainability aspects of chemicals, materials, products, and processes. Using the framework’s recommendations for advanced materials and the OECD WPMN expert workshop output, the researchers simulated various exposure scenarios for the aerogel mats and conducted two hazard screening assays.

Simulating exposure scenarios indicate inhalation of aerosols by workers

The release of aerosols by four different inorganic aerogel mats was simulated using three occupational exposure scenarios realistic for their intended use as building insulators. The study indicated that aerosols may be released during mat installation, posing an inhalation risk for workers. There was no expected exposure to consumers or the environment during use. All four aerogel mats released more respirable dust than conventional materials, i.e. synthetic glass fibers. Around 60% of the dust is likely to deposit in the lung’s alveolar region.

Hazard screening assays

Two tests were conducted to understand the hazards of the collected aerogel dust. The tests measure how the dust’s surface reacts with human serum and how quickly it dissolves in fluids that mimic lung conditions. Both aerogels and conventional insulators had similar surface reactivity, but they differed in how quickly they dissolved in lung fluid.

Screening for safety and sustainability supports safe innovation

The researchers showed how to factor safety aspects into investment decisions for aerogel mats. Sustainability was assessed only qualitatively due to data confidentiality, material novelty and niche use. However, using an SSbD approach to develop products with advanced materials promotes economically viable and safe innovation.

Reflections by RIVM

The current HARMLESS study mainly focused on the safety aspects of the aerogel mats. Without further exposure and hazard data the Early4AdMa approach had limited value in ranking different materials for safety aspects. However, this approach is one of several methods (SUNSHINE Screening Level Approach, ASINA, the Cefic guidance(PDF)) to identify safety and sustainability hotspots early in the innovation process. Recently, HARMLESS also published the Advanced Materials Earliest Assessment (AMEA) approach. This proposes simple assessment steps and guidance for design rules. These are meant to be applied by innovators in early material development phases (ideation, business case and laboratory phases). This AMEA approach aims to provide a structured approach exploiting the available knowledge at each phase of the innovation process, starting from the intended product, application and global region. The approach also exploits knowledge from the conventional material in the same application, of which the sustainability benefits and sustainability challenges often constitute the motivation for advanced material development. All these methods need further development.

These early screening approaches are often qualitative or semi-quantitative, relying primarily on expert judgment. The more comprehensive approaches, such as the JRC’s SSbD Framework, generally require more data. A combination of such approaches is therefore necessary. In effect, starting with early screening safety and sustainability approaches and increasing the available data to allow the more comprehensive approaches.

This study highlights the challenges of identifying safety and sustainability warnings when limited data is available. A monitoring and evaluation system would help to disseminate these early identified safety and sustainability hotspots and to identify regulatory gaps. This allows timely actions to be taken where necessary, either by developers and/or regulators.