Unilever, Clariant and Vantage pioneer next-gen chemical safety for reducing animal testing under REACH

22 Jul 2024 --- Unilever, Clariant, Vantage and Environmental Resources Management researchers present a new method for testing the safety of chemicals to ensure that animals are used as a “last resort.” The industry is seeking solutions at the EU’s behest. 

A case study in Toxicology presents a framework for Next Generation Risk Assessment (NGRA) applied to sodium-2-hydroxyethane sulfonate (sodium isethionate or SI), a common industrial chemical. Researchers believe the new approach could sustainably transform chemical safety in the workplace:

“Workers can be exposed to a variety of chemical substances as part of their daily roles, which can have a detrimental effect on health if not assessed and managed adequately,” warns the paper.

The study’s NGRA framework is presented as an alternative to traditional occupational safety assessments. By focusing on human-relevant data and advanced modeling techniques, it believes this is a safer and more ethical approach to managing chemical exposure in the workplace.

The paper indicates that the traditional approach to occupational safety is heavily based on animal testing to establish exposure limits. However, animal testing has been increasingly criticized for its ethical concerns, high cost, time commitment and questionable relevance to human health. 

NGRA for SI safety assessments
The study introduces NGRA, an exposure-driven methodology that uses new approach methodologies (NAMs) to improve safety decision-making processes.

The NGRA framework provides safety assessment, which reduces reliance on animal testing and allows for tailored risk management.“Application of NGRA has been largely restricted to assessments of consumer use of cosmetics and is not currently implemented in occupational safety assessments, e.g., under EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals),” reads the paper.

“By contrast, a large proportion of regulatory worker safety assessments are underpinned by toxicological studies using experimental animals. Consequently, occupational safety assessment represents an area that would benefit from increasing application of NGRA to safety decision making.”

The researchers examined SI using NGRA to show an approach that combines exposure estimates, advanced in vitro bioactivity assays and physiologically based kinetic (PBK) modeling. The PBK model predicted SI internal exposure levels.

The study estimated occupational exposures using a life cycle assessment of SI. The data confirmed the safety of workers exposed to SI using current factory-specific risk management practices.

The researchers believe this approach provides a more refined safety assessment, reduces reliance on animal testing and allows for better risk management catered to workplace conditions.

Notably, the bioactivity assays revealed that SI has limited bioactivity, which researchers say is consistent with historical animal data and in silico profiling with low in vivo potency.

NAMs for natural cosmetic ingredients
With the demand for safe and sustainable personal care, a recent review in Cosmetics reveals safety aspects and EU regulatory frameworks concerning natural cosmetic ingredients to ensure consumer health. It suggests NAMs as an ethical and scientifically progressive approach to toxicity testing.

The Local Lymph Node Assay, Derek Nexus and microfluidic models are promising methods for for skin sensitization testing.In Europe, all cosmetic products undergo safety testing under the EU Cosmetic Regulation (1223/2009) to rule out potential hazards such as microbial contaminants, chemical pollutants and allergens.

However, the researchers note that products, especially those with water-based formulations, are susceptible to microbial growth if not properly preserved. Potential chemical contamination presents a significant challenge for natural cosmetics. When they surpass allowable limits, heavy metals like lead and mercury — which are occasionally found in botanical extracts or essential oils — pose serious health risks. 

The review acknowledges that the industry is increasingly adopting NAMs to address ethical concerns and comply with EU regulations banning animal testing for cosmetics. According to researchers, testing methods, such as in vitro and in silico techniques, offer promising alternatives to traditional animal testing for local toxicity effects.

The researchers highlight that skin sensitization is an essential final step when evaluating the safety of cosmetic ingredients, especially those sourced from natural sources. This toxicological endpoint assesses allergic reactions.

Historically, skin sensitization testing relied on animal models such as guinea pigs and mice, employing tests like the guinea pig maximization test and the Buehler occluded patch test.

In recent years, NAMs have gained prominence. The Local Lymph Node Assay, for instance, measures lymphocyte proliferation post-exposure and has replaced older animal-based tests due to its sensitivity and reduced animal suffering, details the review.

It spotlights other in silico tools, such as modeling software Derek Nexus, which predicts skin sensitization potential, and emerging microfluidic models, which promise to mimic skin physiology for sensitization testing.

The authors credit policy shifts, including the EU ban on animal testing, for driving the standardization and acceptance of NAMs for skin sensitization testing. The EU Reference Laboratory for Alternatives to Animal Testing is noted for playing an important role in endorsing these methods.

By Venya Patel