Distribution and Marketing sludge/biosolids products

                           Sludge/biosolids -- Compost and soil amendments

                                                   Unknown Dangers

1986 EPA Study Development of a Qualitative Pathogen Risk Assessment Methodology for
Municipal Sludge Landfilling

1988 EPA Study     Occurrence of Pathogens in Distribution and Marketing Municipal Sludges
             William A. Yanko,  County Sanitation Districts of Los Angeles County,
"Although the use of sludge as a soil amendment is attractive, it is not without potential health risks. Toxic
chemicals, including heavy metals and industrial organics, may enter the food chain and present long-term
health risks."

significant increases in bacterial populations, including salmonellae, occurred during subsequent
production of commercial s o i l amendment products.

1988 EPA Study -- Trace Organics and lnorganics in Distribution and Marketing Municipal Sludges
Rodger Baird and Sylva M. Gabrielian,   County Sanitary Districts of Los Angeles County,

Efforts to characterize major unknown organic components were limited to computer comparisons of
GC/MS peaks to the NBS mass spectral library. In none of the cases was a tentative identification made.

Manual review of those components with a high degree of fit with an NBS library compound (>8O%) allowed probable
compound class assignment for many peaks. Virtually all of the major components classified appeared to be aliphatics
or carboxylic acid type compounds. A majority of the sample extracts exhibited a hydrocarbon "hump" in the ion
chromatograms. The peaks reviewed, therefore, were superimposed on this background. As a result,a significant
portion of the major peaks were multi-component peaks whose identities remain completely unknown.