This innovative approach not only addresses ethical concerns regarding animal use but also aims to enhance the accuracy of toxicity predictions for human health, marking a significant step towards global regulatory acceptance of humane testing practices.

An international multi-lab effort, including one in India, is validating a non-animal method to test for inhalation toxicity of surfactants that are usually used in industrial segments, including pharmaceuticals.

The initial pilot study was undertaken by PETA Science Consortium International, the US Environmental Protection Agency (EPA), and Belgium’s Flemish Institute for Technological Research (VITO), and it showed that “laboratory-grown human airway models, instead of animals, can be used to assess the inhalation toxicity of surfactants, a class of chemicals commonly found in products ranging from soaps and cleaners to agricultural formulations,” Peta said.

A paper co-authored by the scientists - “Human in vitro airway models to assess point-of-contact respiratory toxicity of surfactants and derive human equivalent concentrations after single dose exposure,” was published in Toxicological Sciences, the animal welfare group said.

“The traditional way of inhalation (tests) is exposing rats ...to that chemical and then ...depending upon whether it is a short study or a long term study, they are exposed to that chemical and then they kill the animal to see where it went in the lungs,” Dr Ankita Pandey, PETA India Science Policy Advisor, told businessline.

“Anatomical and physiological differences between human and rat respiratory tracts limit the ability of rats to reliably predict how inhaled chemicals will affect humans,” the organisation said.

The human cell-based test method used in the pilot study was also fed into an international, multi-laboratory effort funded and coordinated by PETA scientists. They included four labs from India (Gujarat), the United States, the United Kingdom, and Switzerland. The non-animal method uses laboratory-grown human airway tissue models that mimic features of the human respiratory tract, including mucus-producing cells and tiny hair-like structures called cilia that beat rhythmically.

This initiative demonstrated that these tissues can be shipped internationally and used by laboratories in different countries – an important step toward broader regulatory acceptance and global use, it said.

In August 2026, the project proposal was added to the work plan of the Organisation for Economic Co-operation and Development (OECD) Test Guidelines Programme. While additional testing, analysis and documentation are still needed, this represents a milestone in the path to global adoption of this non-animal method, Peta said.

The study “addresses regulatory needs by focusing on characterising the potential risk for respiratory tissue irritation. By leveraging human-relevant in vitro models, it may provide more predictive data than traditional animal tests, offer mechanistic insights into the underlying biological responses, and contribute to reducing animal use while supporting modernised, science-based safety assessment. This work represents an important step toward replacing animal testing with more modern and ethical approaches,” she said, adding that surfactants are commonly used pharmaceutical excipients that improve drug solubility, stability, absorption, and delivery.

“We are currently analysing data from the study. The next step is to draft a validation report summarising the study’s findings for submission to the OECD,” the Peta representative said, of a process that included convening an independent panel of experts to review the report, and submit the peer-reviewed document to the OECD for consideration.

“The formal process from inclusion on the OECD work plan to final Test Guideline adoption can take 3-7 years. During this period, the method undergoes rigorous scientific evaluation of the method by representatives of the 38 OECD member countries, who assess the method’s scientific robustness, reproducibility, reliability, and regulatory relevance before deciding its inclusion as an OECD test guideline,” the Peta representative said.

“Before pharmaceuticals, pesticides, and other chemicals are bought and sold, regulatory agencies require testing to assess their potential toxicity to humans and the environment. Millions of animals are used in these tests each year, many based on methods developed decades ago,” the organisation said.

Published on September 21, 2026