Are deposit-refund systems effective in managing glass packaging? State of the art and future directions in Europe.

Glass packaging gives rise to major environmental concerns because it develops more greenhouse gas emissions than plastic packaging and its improper discarding causes the loss of high-quality desired resources. The reuse and recycling of glass packaging reduces greenhouse gas emissions and the use of newly extracted resources sand and soda. To mitigate the environmental impacts of glass packaging, countries have set-up various collection and recycling systems, which are often organized and financed through extended producer responsibility schemes. The most common collection systems are deposit-refund systems (DRS), separate collection in drop-off containers and comingled collection with lightweight packaging waste. By the end of 2035 a minimum of 65 % of glass packaging waste must be prepared for re-use and/or recycled within the EU Member States and thus proper policies and solutions should be adopted to achieve this target. In this sense, the present study aims at verifying if deposit-refund systems and their different configurations affect glass packaging waste reduction and recycling/recovery. To achieve this aim, annual data regarding consumption and recycling/recovery of glass packaging for each European Economic Area/European Free Trade Association (EEA/EFTA) country were extracted over the time period 2010-2019. By using the selected European countries as units of analysis, a hybrid methodology was developed which includes the analysis of variance (ANOVA) and other descriptive statistics. Findings show that the different waste management systems affect neither the amount of glass packaging consumption nor the glass packaging recycling/recovery. In countries which adopt DRS, not more glass packaging per capita was retrieved than in countries which adopt other collection and management systems. In fact, it turns out to be a mechanism that allows for high quality glass packaging collection avoiding its ending up in landfills, but it does not influence consumption choices and the subsequent potential waste production. The adoption of DRS-based collections does not result necessarily in a successful management model for glass packaging. Since setting up additional drop-off collection points and recovering mechanically glass from municipal solid waste (MSW) does not result in glass qualities to be used in glass packaging, DRS represent still the sole progress towards a more circular economy.