Manure Pathogen Survival Study description for Landisville Discovery Day

Research addressing the time interval required between the application of animal manure, to agricultural lands, and the harvesting of produce crops from these manure-amended soils

The Environmental Microbial and Food Safety Laboratory of the United States Department of Agriculture, Agricultural Research Service (USDA-ARS) has been working in collaboration with the University of Maryland Eastern Shore (UMES) and the Food and Drug Administration (FDA) Office of Produce Safety to collect scientific data to support the proposed FDA rules listed in the “Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human Consumption”.   Specifically, this field research addresses the time interval required between the application of animal manure, to agricultural lands, and the harvesting of produce crops from these manure-amended soils.   Different types of manure along with different soil types, environmental, and biological factors are expected to influence the survival of pathogenic bacteria in the manured-amended soil in comparison to non-amended soil.  In lieu of using pathogenic bacteria, this field research study is using non-pathogenic strains of both Escherichia coli and E. coli O157:H7 and measuring their decline in soils amended with various animal manures (dairy cattle, poultry, and horse).    SEAREC is one of the three geographically distinct sites, with different soil types, involved in the large comparison study: Princess Anne, MD (University of Maryland Eastern Shore, UMES); Beltsville, MD (USDA-ARS-Beltsville Area Research Center (BARC) are the others.  The research experiments are being conducted by establishing uniform size field plots (2m x 1m) at all sites with application of either low or high amounts of multiple-strains of E. coli to the replicated plots.  Data collection, microbial, and molecular analysis are ongoing at all sites and also will involve separate plots with spring application of manure and later leafy green cropping to evaluate transfer of E. coli from soil to leafy greens.  It is anticipated that the data collected from these studies will directly impact the proposed produce safety rules issued by FDA.  Preliminary results indicate that seasonality, manure, and soil type influence the survival of E. coli in manure-amended soils used to grow produce and that manure prolongs survival of these bacteria in soils.

About the Researchers:
Pat Millner and Manan Sharma are Research Microbiologists at EMFSL, USDA ARS.  Their research focuses on the persistence of enteric bacterial pathogens like Escherichia coli O157:H7 and Salmonella spp in pre-harvest, produce growing environments, including organic agricultural systems.  Their research also examines routes of contamination of leafy green (lettuce, spinach) through contaminated soil, water, and various decontamination methods for irrigation water and contaminated leafy greens.

Fawzy Hashem is an Associate Professor at the University of Maryland Eastern Shore.  His research focuses on environmental microbiology, microbial source tracking, biological control, bioremediation, phyto-remediation, plat-microbe interactions, environmental pollution and food safety.

Contact Information:
Pat Millner:
Phone:  301-504-5631

Manan Sharma:
Phone:  301-504-9198

Fawzy Hashem:
Phone:  410-651-6632