Microbiological aerosols from the application of liquid sludge to land

Abstract

A detailed aerosol study was conducted at four locations: two sites with tank truck application, and two sites with spray application. From five to eight aerosol monitoring runs were made at each of the four sites, and a special enterovirus aerosol run was conducted at one of the spray sites. There was some evidence of aerosolization at the tank truck sites and strong evidence at the spray sites, particularly of fecal coliform and fecal streptococci. Modeling of the results proved difficult and there is considerable statistical uncertainty in the data presented. No human enteric viruses were detected (less than 0.0016 pfu/cubic m) at a distance of 40 m downwind from the spray gun. The inability to detect enteric viruses in the air was most likely the result of low concentration in the sludge and adsorption into the solid matter in the sludge which is not readily aerosolized. 10 references.