Maximum component pollutant limits by the US EPA

The term "pollutant" is defined as part of the EPA 503 rule. The components of sludge have pollutant limits defined by the EPA. "A Pollutant is an organic substance, an inorganic substance, a combination of organic and inorganic substances, or a pathogenic organism that, after discharge and upon exposure, ingestion, inhalation, or assimilation into an organism either directly from the environment or indirectly by ingestion through the food chain, could, on the basis of information available to the Administrator of EPA, cause death, disease, behavioral abnormalities, cancer, genetic mutations, physiological malfunctions (including malfunction in reproduction), or physical deformations in either organisms or offspring of the organisms."[22] The maximum component pollutant limits by the US EPA are:

Reference 1: Ceiling concentration (milligrams per kilogram).

Reference 2: Cadmium, Copper, Lead, Mercury, Molybdenum, Nickel, Selenium and Zinc.

Source: http://en.wikipedia.org/wiki/Sewage_sludge