The public health safety of using human excreta from urine diverting toilets for agriculture: the Philippine experience

To determine the safety of using human excreta in agriculture, an observational study was conducted to determine the length of time necessary to eradicate parasitic ova and pathogenic bacteria in human excreta kept in the storage vaults of urine-diverting dehydration toilets in Cagayan de Oro City, Philippines for ten (10) months, from August 2007 to May 2008. The study was conducted using seven (7) urine-diverting toilets. Baseline data for parasite ova and pathogenic bacteria were taken and duly recorded. Results show that microorganisms do not pose a public health threat if human excreta from UDDT vaults are used in agriculture. However, helminth eggs, particularly those of Ascaris lumbricoides, may still be infective and six months may not be sufficient to dehydrate human feces and render them safe for agricultural use. Secondary treatment is strongly recommended to render human excreta safe for agricultural use.