ReviewMoss bag biomonitoring: A methodological review

Although the moss bag technique has been used for active biomonitoring for the past 40 years, there is still no standardized protocol that enables application of the technique as a tool to monitor air quality. The aim of this review paper is to evaluate the degree of standardization of each of the variables that must be considered in applying the technique (i.e. the variables associated with preparation of the moss and moss bags, exposure of the bags, and post-exposure treatment). For this purpose, 112 scientific papers that report the methods used in applying the moss bag technique were consulted. Finally, on the basis of the conclusions reached, we propose a protocol that will enable each of these variables to be investigated separately, with the final aim of developing a standardized methodology.

► The moss bag technique has still not been standardized, 40 years after it was first used. ► Routine use of the technique as a tool for air monitoring is not possible. ► A methodological review of 112 studies on moss bag monitoring was carried out. ► The degree of standardization of each method varies. ► A new harmonised protocol for the application of the moss bag technique is proposed.