Sanitisation of dog faeces through home composting

Home composting is widely promoted as an environmentally sustainable way to recycle and reuse organic waste. Yet, little evidence exists on whether dog faeces, often considered too hazardous for home composting, can be sanitised for safe use in domestic food gardens. This study evaluated pathogen reduction in dog faeces home composted outdoors at ambient temperatures through two pilot-scale trials (25 L) and one household-scale trial (160 L). Composting process parameters, including temperature and biological stability, were measured to explore factors influencing sanitation. Fresh dog faeces contained E. coli, Salmonella spp., and occasionally Campylobacter spp., but no target canine soil-transmitted helminths were recovered. Pilot trial 1 (7 months) produced composts of low-moderate stability that exceeded sanitation guidelines for E. coli and Salmonella spp., whereas Pilot 2 (15 months) yielded stable composts with no detectable bacterial pathogens. In the household trial, dog faeces co-composted with food waste for 12 months produced fully sanitised composts that met Australian AS4454 and World Health Organisation guidelines, despite temperatures remaining below disinfection thresholds of ≥55°C. Compost stability, rather than thermal exposure, was the primary factor influencing pathogen inactivation, highlighting the roles of microbial competition and sufficient processing time in low-temperature come composting systems containing dog faeces. This study provides the first robust evidence that dog faeces, when composted properly and allowed to stabilise, can be safely transformed into a low-risk soil amendment suitable for use edible plants. The findings challenge long-held assumptions about home composting limitations and expand sustainable waste-management options for dog-owning households.