A system and a method for studying or predicting the interaction between a lung and an aerosolized agent. The system comprises an aerosol generator (10) sealingly connected to an exposure arrangement adapted to provide a transport aerosol flow from an aerosol holding chamber of the aerosol generator (10) to a flow junction; and an exposure aerosol flow from the flow junction for distribution to an exposure organ with breathing capacity thereby a providing a residual aerosol flow transported away from the flow junction. The exposure arrangement further comprises a flow rate monitoring device located upstream the flow junction for monitoring the transport aerosol flow, a device for measuring the aerosol particle concentration located downstream the flow rate monitoring device, and optionally a flow control function for controlling the transport aerosol flow. Using the system for predicting the interaction between a lung and an aerosolized agent minimizes the loss of the agent.