Elimination of irritating compounds during chronic exposure to gases

Ammonia (NH3, a degradation product of urine) and intestinal gases which accumulate in the experimental circuit during the long-term experimental exposure of rats to gases might cause disturbing irritation in the behavior of the animals. A relatively simple and cheap experimental arrangement has been suggested for the elimination of these irritating compounds. This system also guarantees the maintenance of a constant concentration of the investigated gases. In order to facilitate the comparison of the results of various studies, the standardization of the basic experimental procedure for the long-term exposure to gases has been suggested.