Research progresson the transport timescales of substances in estuaries and coastal areas in recent years was reviewed from three aspects, including the concepts, the research methods and the applications of transport timescales. The advantages and limitations of the current mathematical models for the computation of substance transport timescales, especially the progress of the constituent-oriented age and residence time(CART)theory are discussed emphatically in this paper. Aiming at the shortcomings of the current non-conservative substance transport timescales, it is pointed out that the interaction between adsorptive pollutants and suspended particles should be considered to describe the transport timescales completely. Strengthening the study on the transport timescales of non-conservative materials, sediments and adsorptive pollutants will help to reveal the transport characteristics of complex substances. The CART theory should be applied to calculate the transport timescales of non-conservative substances, sediments and the pollutant transport process that considers the interaction with sediments.