[Airborne microorganisms in animal stables: stability of endotoxins in the environment].

The stability of endotoxins was investigated in potential sources (feed-stuff, litter, water, excrements, surface dust) of that air contaminant and in the airborne state. No changes in the endotoxic activity were found in materials with high dry matter (straw, hay, dried faeces) during 84 days. In manure samples stages of increasing and decreasing endotoxic activity were observed. In water a continuous decline of the endotoxic activity was found. However this process was characterised by half-life periods on a weekly scale. Bacterial degradation seems to be responsible for that loss of endotoxic activity.