Tuesday, 16 April 2019 12:55

Inhalation toxicology: Cultex System successfully validated Featured

The company CULTEX Laboratories, based in Hanover, Germany, has successfully completed a validation study with its in-vitro inhalation system. Thus there is now a reliable and reproducible method avialable which allows a replacement or at least a reduction of animal experiments in acute inhalation toxicity tests with aerosols.


The currently accepted guidelines to test for acute inhalation toxicity TG 403 (Acute Inhalation Toxicity), TG 436 (Acute Inhalation Toxicity - Acute Toxic Class Method), and TG 433 (Acute Inhalation Toxicity: Fixed Concentration Procedure ) prescribe animals, especially the rat. In the tests, the animals are immobilized in a holding apparatus in order to inhale the test pollutants for a certain period of time. The animals are then observed, sampled if necessary and finally killed to examine the organs.

The CULTEX® Radial Flow System (RFS) is an in vitro system consisting of several modules. Potential air pollutant particles are applied to human bronchial epithelial cells with a specially developed atomizer. The human lung cells are exposed at the air-liquid interface (ALI).

CULTEX® Radial Flow System (RFS).
Foto: CULTEX Laboratories.

Based on a pre-validation study which has been successfully completed earlier in terms of transferability, stability and reproducibility, the methodology were optimized and additionally prediction models for acute inhalation hazards were developed.

The validation study evaluated the cell viability of A549 cells after exposure to 20 test substances in three independent laboratories. Cytotoxicity results were compared with controls and used as an indicator of toxicity.

The correspondence of the results with the available in vivo data was 85% with a specicity of 83% and sensitivity of 88%. Reproducibility between laboratories was 90-100%. As a result, the CULTEX®-RFS was assessed as a transferable, reproducible and well-functioning system for the assessment of acute pulmonary cytotoxicity of airborne particles.

The test system is suitable for testing a wide range of substances such as single gases, gas mixtures, particle-containing aerosols, etc.  

Original publication:
Tsoutsoulopoulos, A., Gohlsch, K., Möhle, N., Breit, A., Hoffmann, S., Krischenowski, O.,
Mückter, H., Gudermann, T., Thiermann, H., Aufderheide, M. & Steinritz, D. (2019).
Validation of the CULTEX® Radial Flow System for the assessment of the acute inhalation
toxicity of airborne particles. Toxicology in Vitro. https://doi.org/10.1016/j.tiv.2019.03.020.