Health Risks of Manure Spray Irrigation

This new section is under construction as we assemble a scientifically supported base of information on this topic.

Please refer to the link to the EPA website below for a list of pathogens contained in untreated animal manure. Land application of liquid manure is already linked to surface and ground water contamination. Consider the consequences to human health once these pathogens are airborne via spray irrigation techniques.

http://www.epa.gov/agriculture/ag101/impactpathogens.html

But don’t just take our word for it.

From a memo by Robert Thiboldeaux, Ph.D., Toxicologist, Wisconsin Division of Public Health to Ken Johnson, Regional Water Leader, WDNR SCR: “Where airborne pathogens are deposited on ready-to-eat crops or on surfaces handled by adults or young children, accumulation could occur throughout the irrigation period, and risk of infection would be dependent upon the concentration of viable pathogens on the food or handled surface. In the case of E. coli O157:H7, the infectious dose has been estimated to range from 1 to 100 colony forming units (CFUs). For Salmonella, an infective dose my be as low as 15-20 cells.”

“Interrupting human exposure to feces, with its attendant risk of infection by bacterial, viral and parasitic pathogens, is at the foundation of public health practice.”

Worst-case conditions that lead to the greatest exposure and risk of infection are nighttime low-wind stable conditions which maximize the inhalation pathway; and high-wind conditions which maximize the deposition and produce ingestion pathway.–from Microbial Risk Assessment and fate and Transport Modeling of Aerosolized Microorganisms at Wastewater Land Application by Idaho Department of Environmental Quality.

“In addition to steps to avoid infectious exposure to off-site receptors, land application of manure liquid must be managed to avoid unacceptable off-site levels of hazardous air pollutants, particularly hydrogen sulfide and ammonia.”

“NR214 allows for the regulation of land-applied wastes with regard to aesthetic impacts. DHS recommends that the land application of manure liquids be managed to minimize impacts, particularly nuisance odor, that might inhibit the full use and enjoyment of neighboring private residences. Nuisances, though qualitative, are important to those perceiving the nuisance, and raise the potential for land-use conflicts.”

“DHS recommends that the permit include regulatory means, such as the monitoring of both applied liquid manure and deposition in downwind areas, to assure that any permit conditions to avoid aerosolization, drift and odor control are met.”