Urban and peri-urban lands have potential for local, sustainable food production, but their soils are often degraded or unsafe due to human activity. This study examines how compost made from urban and industrial organic waste can help restore soil for agroecological farming.

Conducted in Rosario, Argentina, five types of compost were made from chicken manure, cow rumen, brewer’s byproducts, and urban leaves. These were tested as growing substrates for radishes and lettuces. The study assessed the quality and limitations of these composts in improving soil fertility, and their potential for supporting closed-cycle, sustainable agriculture. Various physical, chemical, and microbiological tests were performed, including checking for pollutants like heavy metals and agrochemicals. The results showed that while composting improved soil conditions, some pollutants persisted. However, vegetable crops generally contained pollutant levels below harmful thresholds, highlighting the soil and compost's filtering capacity.