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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Environmental Microbial & Food Safety Laboratory » Research » Publications at this Location » Publication #337535
Research Project: Characterization and Mitigation of Bacterial Pathogens in the Fresh Produce Production and Processing Continuum

Location: Environmental Microbial & Food Safety Laboratory

Title: Assessment of indicator bacteria and Aeromonas spp. in surface and nontraditional irrigation water: a conserve study

Author
item SOLAIMAN, SULTANA - University Of Maryland
item CALLAHAN, MARY - University Of Maryland
item ALLARD, SARAH - University Of Maryland
item MICALLEF, SHIRLEY - University Of Maryland
item MAY, ERIC - University Of Maryland Eastern Shore (UMES)
item HASHEM, FAWZY - University Of Maryland Eastern Shore (UMES)
item PARVEEN, SALINA - University Of Maryland Eastern Shore (UMES)
item KNIEL, KALMIA - University Of Delaware
item Sharma, Manan
item SAPKOTA, AMY - University Of Maryland

Submitted to: International Association for Food Protection
Publication Type: Abstract Only
Publication Acceptance Date: 3/17/2017
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Introduction: The use of surface and nontraditional irrigation water (SNIW) (pond, tidal and non-tidal river water, reclaimed wastewater) is one way to conserve groundwater. However, SNIW may serve as reservoirs and vehicles for under-recognized enteric pathogens, spreading localized contamination during fresh produce cultivation. Purpose: To investigate the presence of Aeromonas spp., gram-negative bacteria commonly found in water environments that can cause gastrointestinal disease, and bacterial fecal indicators (total coli forms (TC), Escherichia coli, Enterococcusspp.) in SNIW in Maryland. Methods: Water samples from 2 ponds, 2 tidal rivers, 4 non-tidal rivers/creeks and 3 reclaimed wastewater treatment plants were collected in Maryland for over a period of four months. Bacteria were enumerated using a standard membrane filtration method on MI (E. coli/TC) (n=49), mEI (Enterococcus) (n=49) and ADA-V (Aeromonas spp.) (n=43) agars. Water temperature, pH and turbidity were measured using a ProDSS multi-parameter meter. Results: All samples tested (43/43) were positive for Aeromonasspp. The prevalence of E. coli, TC, Enterococcusspp. and Aeromonasspp. in water samples ranged from undetectable -4.1, 3.4-5.9, undetectable -4.6 and 2.5-5.5 Log CFU/100mL of water, respectively. Mean counts were 2.9, 4.7, 3.3 and 4.3 Log CFU/100ml, respectively. Non-tidal fresh water samples harbored significantly higher levels of E. coli and enterococci compared to pond and reclaimed water (p<0.05). Aeromonascounts were significantly correlated with E. coli, TC and enterococci (R2=0.42, 0.36 and 0.43; p<0.0001), respectively. Aeromonaspopulation levels were also weakly positively correlated with water temperature (R2=0.17; p<0.01) and turbidity (R2=0.12; p<0.05). Significance: This study is part of a two-year sampling effort to characterize the microbiological quality of surface and nontraditional water sources. Results show that surface and nontraditional irrigation water harbors high levels of Aeromonasspp. that correlate with bacterial fecal indicators and physical parameters of water. Risks of under-recognized pathogens in fresh produce need to be assessed.