Most of the municipal green waste consisted of garden waste (M±SD: 70±11% FS). The proportion of food losses amounted to 27±11% FS. There tended to be more food losses in urban communities than in peri-urban and rural communities.

Most food losses were kitchen waste (74±7%), followed by cooked and processed other foods (12±5%) and uncooked fruits and vegetables (11±4%). Meat and fish accounted for 2±1%, dairy products, eggs and margarine for 1±0.4%. Around 36% of the food losses could be avoided.

Based on the results of this study, it can be assumed that around 157,000 tons of FS food from households is disposed of with green waste every year. This corresponds to 17.8 kg FS per person and year.

Compared to 2018, food losses in green waste increased by 35%. Between 2012 and 2022, the proportion of food that was disposed of with refuse decreased slightly (refuse bag analysis 2022). The increase in food losses in green waste could therefore be partly due to a shift in disposal from refuse to green waste.

The proportion of total foreign matter in municipal green waste remained roughly the same as in 2018. The proportion of non-degradable plastics increased by 57% FS.

A comprehensive evaluation and discussion of the results is provided in the final report.

Since 2012, there have been increasing activities in Switzerland, both at the research level and in the context of legislation and implementation, to quantify waste that arises along the food chain and to introduce measures to avoid or recycle it. The FOEN is striving to create a reliable and uniform database along the entire food chain, i.e. from the primary producer through processing, storage and distribution to consumption, and to update this regularly. In addition, it has the mandate to ensure that green waste for composting and fermentation is not too polluted. Between 2014 and 2017, corresponding studies were carried out and basic data collected at the levels of agricultural production, industrial processing, retail trade and gastronomy. At the consumer and private household level, the main producers of food waste, the composition of the separately collected green waste, including the fractions of food waste and foreign matter, was collected for the first time in 2018. To obtain an overall picture of municipal waste in Switzerland and to check the success of measures against food waste, the composition of separately collected green waste was analyzed for the second time in autumn 2022 and spring 2023.

• Analysis of the composition of separately collected green waste from Swiss households
• Analysis and assessment of the content of avoidable and non-avoidable food waste
• Analysis and assessment of the content of plastics and other foreign substances
• Analysis of the development over time