A fate model of pathogenic viruses in a composting toilet basedon coliphage inactivation

A composting toilet using sawdust as a matrix has the potential to trap pathogens that might occasionally be contained in humanfeces. Therefore, care should be taken when handling the sawdust. It should also be noted that pathogenic viruses tend to have strongertolerance than pathogenic bacteria. The fates of several species of coliphages, T4, , Q and MS2, in sawdust were investigated asa viral model. The fates of coliphages were significantly different among them, and they changed in response to temperature and thewater content of the sawdust. As the results, T4 coliphage had the strongest tolerance and Q had the weakest one in sawdust. It wasestimated the days required to decrease virus to a safe level based on a risk assessment. According to the rates of Q and T4, 15 daysand 167 days were required respectively for a safe level of infection risk based on actually operated composting toilet condition. Thus,it was significantly different depending on the species and sawdust conditions.