RIFM and SenzaGen expand collaboration, focus on skin sensitization


“Skin is the largest organ of the body,” says Mihwa Na, PhD, “and it’s the part of us that is most exposed to fragrance ingredients. One of the most important jobs for RIFM scientists is to help ensure that we can safely enjoy our favorite fragranced products.”

Dr. Na leads the skin sensitization endpoint at the Research Institute for Fragrance Materials (RIFM), along with her colleagues Maura Lavelle, MS and Dr. Isabelle Lee, conducting safety assessments and research projects that address an ingredient’s potential to induce allergic reactions in the skin.

“Skin sensitization is a rare but serious allergic response,” Dr. Na explains, “so we must identify the dose at which a fragrance ingredient may induce this condition.”

(Ask a RIFM Scientist: How is skin sensitization different from skin irritation?)

For the last three decades, RIFM has drawn on its substantial collection of historical study data to predict exposure levels below which the science tells us that skin sensitization is not expected to occur. In a recently published, peer-reviewed paper, Dr. Na and colleagues analyzed the results of 30 years of CNIH (short for “Confirmation of No Induction in Humans”) studies, which RIFM scientists have used to confirm minimal-risk exposure levels ethically.

But science is always evolving. That is why RIFM is collaborating with SenzaGen, a biotech company that has developed a skin assay called GARD™ (Genomic Allergen Rapid Detection), which predicts the ability of ingredients to induce skin sensitization.

GARD uses a human cell line called SenzaCell, which acts as an in vitro (or, Petri dish) model of human dendritic cells, which communicate with T cells to start up the immune process. SenzaGen’s new GARDskin Dose-Response refines GARD’s results, revealing the specific dose at which sensitization would be expected to occur.

“Access to more detailed information on skin sensitizing ingredients is important for companies developing products—and ultimately for all of us who use fragranced products,” says Axel Sj√∂blad, CEO of SenzaGen. “We look forward to this collaboration and to contributing to progress in terms of sustainability and ethics in testing.”

Further reading: Since 2020, RIFM and SenzaGen have collaborated on developing an application to assess the potential of fragrance ingredients to induce skin allergies when exposed to sunlight (photosensitization).