Advancing Fragrance Safety at SOT: Nikaeta Sadekar, PhD, DABT, presents on local respiratory effects
Next week, several RIFM scientists will join over 5,000 toxicologists participating in more than 70 scientific sessions and offering over 2,000 poster presentations at the Society of Toxicology (SOT) 62nd Annual Meeting.
During the event, Nikaeta Sadekar, PhD, DABT, Senior Scientist, Respiratory Toxicology, will present two collaborative local respiratory toxicology studies.
In the first, Dr. Sadekar and scientists at the Institute for In Vitro Services (IIVS), Charles River Laboratory (CRL), and Fraunhofer Institute for Toxicology and Experimental Medicine (Fraunhofer ITEM) looked at three different in vitro models representing different areas in the human respiratory tract.
“Humans experience a far more acute sense of smell than we give ourselves credit for,” Dr. Sadekar explained. “Consequently, the exposure to fragrance ingredients across all products consumed, even by the highest users, is extremely low. For this reason, 99% of all fragrance-producing ingredients fall below the most conservative inhalation Threshold of Toxicological Concern, or TTC, the level beneath which there is no appreciable risk of harm.”
“Still,” Dr. Sadekar continued, “studying the impact of exposure to all three regions of the respiratory system is critical because fragrances have such complex physical-chemical properties. Depending on where a fragrance material lands in the respiratory tract, you would use its corresponding in vitro model.”
In the first model, a human primary culture stands in for the upper tract. Human primary cell cultures have been recently removed from organ tissue and maintained for growth in a test tube or Petri dish as if they were still in the living body.
In the second model, a region of the lower tract is represented by human lung tissue in an ex vivo, or outside the living being, model.
The third model, representing the alveolar space, consists of an immortalized cell line, which are cells manipulated to proliferate indefinitely to be cultured over several generations.
Dr. Sadekar will present this work as part of the Alternatives to Mammalian Models I poster session beginning at 9:00 AM on March 20th.
“Only in the absence of guideline-conforming data and an appropriate read-across option do we consider exposure-based waiving, or use of the inhalation TTC,” Dr. Sadekar elaborated. “To strengthen our understanding of TTC, we are building an inhalation exposure database using pre-existing historical animal-study data.”
Dr. Sadekar says developing an inhalation exposure database will help RIFM perform safety evaluations in several ways while continuing to avoid animal testing.
Dr. Sadekar and collaborators, the United States Environmental Protection Agency (EPA), Procter & Gamble, Fraunhofer ITEM, and Cosmetics Europe, are pulling more than 1,000 studies from the RIFM Database, EPA’s ToxVal Database, and the Fraunhofer Institute’s Repeated Dose Database to ensure the new Inhalation TTC Database has a robust dataset from which to work.
Dr. Sadekar presents on this work as part of the Risk Assessment I poster session beginning at 2:30 PM on March 20th.
Finally, Dr. Sadekar will join RIFM Principal Scientist Gretchen Ritacco to present on RIFM’s collaborative work with IIVS using in vitro systems to model photosafety and respiratory toxicology at an Ancillary Session and reception on Tuesday, March 21st from 4:30-6:00 PM at the Music Row 3 room in the Omni Nashville Hotel.