Quick Answer
Using humanure on food crops is generally not recommended due to health and safety concerns, but it can be permissible under strict guidelines and proper processing techniques.
Safe Processing Techniques
Composting humanure requires a minimum of three months of aerobic decomposition, with temperatures reaching 131°F (55°C) for at least 15 days. This process reduces pathogens to safe levels, but it’s still crucial to follow proper handling and application guidelines. Compost piles must be regularly turned, maintained, and monitored to ensure adequate oxygen levels and temperatures.
Pathogen Reduction and Testing
Composting humanure is not a guarantee against pathogens, and it’s essential to test the finished compost for pathogens and heavy metals. A minimum of 0.99 log reduction of E. coli and 2.99 log reduction of Salmonella is recommended. Testing should be performed by a certified laboratory using standard protocols. Additionally, maintaining proper compost pile ratios, monitoring pH, and incorporating bulking agents can aid in pathogen reduction.
Safe Application Guidelines
To minimize risks, humanure compost should be applied at a depth of at least 4-6 inches (10-15 cm) and incorporated into the soil. Crops should be rotated and not grown in the same location for at least 2-3 years after applying humanure compost. Crop selection is also critical, as some vegetables, such as leafy greens, are more susceptible to contamination.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.