How does RIFM assess respiratory safety for fragranced products?
When people think about inhaling a fragrance, they might picture a cloud of mist or imagine something heavy hanging in the air. But in reality, what’s present is often just a trace amount, suspended briefly, and quickly dispersing.
That’s why, at RIFM, we prioritize understanding real-world exposure. The respiratory system is complex and efficient. It filters, humidifies, and warms the air before it reaches the lungs. So, when we evaluate fragrance ingredients, we ask: how is this ingredient used? Is it sprayed into the air, rinsed off quickly, or applied to the skin where only trace amounts might be released into the air?
We take those scenarios and model them to reflect how products are used, not in exaggerated lab conditions but in the ways consumers interact with them every day. This helps us build realistic exposure estimates, which are essential to assessing risk.
We also draw on RIFM’s deep history of exploring non-animal alternatives—New Approach Methodologies, or NAMs—such as in vitro systems and computational tools. These methods let us look at cellular and molecular responses to fragrance ingredients, offering high-resolution insight into potential respiratory effects without using animals. Over the years, we’ve worked to refine and validate these approaches so they are robust enough to inform our safety assessments. RIFM does not do any testing on animals for any of its human health endpoints, including respiratory safety.
Another piece of the puzzle is odor threshold research. Humans are incredibly sensitive to smell and can detect some substances at concentrations in the parts-per-billion range. This means a person might perceive a scent long before any physiological response or safety concern is likely. By studying odor thresholds, we gain valuable insight into how detectable a substance is relative to the levels at which it appears in real-world exposures, helping us contextualize perception without confusing it with risk.
When realistic exposure estimates, advanced non-animal science, and decades of toxicological data are combined, you get an evaluation process that’s not just thorough—it’s meaningful. Our job is to provide the science that helps ensure fragrance ingredients are used at levels that are safe under real-world exposure conditions.
Meet Nikaeta Sadekar in Paris!
Dr. Sadekar will highlight RIFM’s respiratory safety process, focusing on real-world exposure, odor thresholds, and the long-standing use of New Approach Methodologies (NAMs) at RIFM’s INFOX® 2025 in Paris on September 29, 2025. Click here to learn more and register for the event.
Principal Scientist Nikaeta Sadekar, PhD, DABT, leads RIFM’s Respiratory Toxicology Safety Assessment and Research Programs.