Several OECD guidelines for testing chemicals have been updated to include nanospecific considerations, which are generally effective. Despite these efforts, challenges remain in standardising the testing of nanomaterials in water, as particles tend to clump together, leading to unstable dispersions and irreproducible results.

Nanoforms of fertilisers or biostimulants sprayed directly onto plant leaves may contribute to more sustainable agricultural practices. However, it needs to be clarified whether the current legislation and methodologies sufficiently addresses the nanospecific properties of these products when assessing the benefits and risks for crops, the environment, and human health.

Two recent reports reviewed existing New Approach Methodologies (NAMs). One focussed on the purpose of regulatory risk assessment and the other on in silico methods for the Safe-and-Sustainable-by-Design (SSbD) of nanomaterials.

The European Scientific Committee on Consumer Safety (SCCS) evaluated information on genotoxicity of titanium dioxide used in cosmetic products. This was triggered by previous similar concerns for food additive E 171 (titanium dioxide, TiO2).

The past few decades of managing the uncertain risks for human and environment associated with nanomaterials have provided crucial insights for ensuring the safe and sustainable development of advanced materials.

The EU-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.

Early4AdMa is an early awareness and action system for identifying emerging issues of advanced materials. Its first application on nanocarriers has revealed several potential issues for nanocarrier materials. These include the applicability of current regulations regarding nanocarriers. In various chemical domains this needs to be critically assessed in more detail. Further, research activities should focus on the carrier’s influence on the active ingredient. What happens to the carrier itself after its work is done also requires attention. Overall, the workshop results demonstrate that the Early4AdMa system may help to identify potential issues with safety, sustainability, and regulation. Provided that these issues are addressed through follow-up actions, this may help regulatory preparedness and contribute to safer materials.

Electronic waste (e-waste) is a valuable source of precious and rare metals. Recycling of e-waste is an essential step towards sustainability. Scientists are currently studying methods to convert the metals present in e-waste into nanoparticles. However, it is important to consider the possible risks associated with this process to maximise its positive environmental impact.

Danish researchers assessed recommendations for adjustments to legislation for nanomaterials published in 2004. While many of these recommendations were partly or fully met, some legislation still needs adjustments for nanomaterials. For example, the definition of nanomaterials differs between legislations. Additionally, instruments to measure nanomaterials and test methods require further development to meet regulatory requirements and enable enforcement. Advanced materials may pose additional challenges in risk assessment. The legislation amendments for nanomaterials may not necessarily identify potential hazards and risks for advanced materials.

Respirable rigid fibres are considered more hazardous than non-rigid fibres. However, there is currently no standardised method to measure fibre rigidity. A new approach uses techniques to identify changes at the molecular level in cells. This approach can distinguish between different types of carbonaceous materials. The researchers could tell the difference between rigid fibres, non-rigid fibres, and non-fibrous carbonaceous materials. For this they looked at which biological pathways were affected. This method will help group different types of fibres into hazard categories based on their rigidity.