Using indicators as a tool to evaluate municipal solid waste management: A critical review.

Indicators have been used to evaluate municipal solid waste management for several decades. This review summarizes the main groups of indicators used for this purpose, as the basis for developing a new proposal in the future. There are a number of problems (scarce or non-existent information, lack of transparency and homogeneity, among others) that prevent the methods proposed so far from being standardized and applied on a more global level. This paper documents 40 sets of indicators and analyzes their main characteristics, strengths, and weaknesses. Based on different authors and on the concept of integrated sustainable waste management, a new framework is proposed that includes all aspects of municipal solid waste management. All the documented indicators were classified according to this framework and compared in order to detect repetitions until a single list was reached. The groups analyzed contained a variety of characteristics, such as the type of indicators (qualitative, quantitative or both) and the level at which they are applicable (municipal, regional, national, international or various levels), among others. An analysis was also performed to determine how many cases each group has been applied to, as well as possible shortcomings that make them difficult to use. Finally, a list of 377 different indicators was obtained, with 49.3% of them focusing on technical aspects of waste management. The component for which most indicators were found was recovery (including recycling, composting, and incineration with energy recovery, among others). From the analysis, the main qualities that an indicator set must accomplish were identified to allow their possible standardization; that is, it must be useful at different geographical and economic levels, include indicators of different types, follow a clear methodology, and cover all aspects of possible interest.