Survival, Growth, and Regrowth of Enteric Indicator and Pathogenic Bacteria in Biosolids, Compost, Soil, and Land Applied Biosolids

Abstract

In the US approximately 60% of all biosolids are currently land applied. Al- though it is known that bacteria in biosolids normally decrease to low or non-detectable levels following treatment, a major concern is that regrowth of pathogens may occur. Specifically the question arises: Does regrowth occur following reintroduction or recolonization of pathogens after land application or during storage under favorable conditions. The following paper reviews available information on survival and potential regrowth of pathogenic and indicator bacteria in biosolids, compost, soil, and land ap- plied biosolids. Based on the literature, a conceptual framework is provided to explain the phenomenon of regrowth.