Sewage sludge definition

Another point of confusion has been the reasonable time part of the definition. As is also true for photodegradation, the time required for biodegradation is a function of exposure conditions (as well as a function of the extent of degradation defined as the end point). Time to reach the defined end point after disposal can be markedly different if the object degrades in sewage sludge, in a compost pile, or in a landfill, even under the same climatic conditions. To this variation, then, must be added differences in ambient temperatures, rainfall, etc. 

By providing more information on the identity of mutagenic compounds, their frequency of occurrence, their possible source, and their levels in sewage treatment plant sludges, our research will assist in the definition of waste management practices. 

For all practical purposes of applying a definition, material manufactured to be biodegradable must relate to a specific disposal pathway such as composting, sewage treatment, denitrification, and anaerobic sludge treatment. 

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