When studying the course and etiopathological mechanisms underlying human lung disorders caused by external factors, it is extremely important to extend the investigations by using an experimental animal model. The advantage of such a model, in respect to well-known ethical limits involved in a human study. Is that one can precisely design the experiment, keep the relevant parameters under strict control and limtate the pathological conditions to be studied. Bronchoalveolar lavage Is a useful toxicological modality for gaining access to the constituents of the lower respiratory tract. Analyses of both soluble and Insoluble contents of the bronchoalveolar lavage fluid are now increasingly being used to monitor the course of lung disorders. The use of an appropriate animal Instillation model provides an insight into the kinetics of the substance in between free lung cells and lung compartments. The bronchoalveolar lavage assay following intratracheal instillation of an experimental animal has proven to be a useful and fast technique for the detection of lung injury caused by toxicants.