Researchers determine factors that influence spinach contamination pre-harvest

Jun 20, 2013

A team of researchers from Texas and Colorado has identified a variety of factors that influence the likelihood of E. coli contamination of spinach on farms prior to harvest. Their research is published in the July 2013 issue of the journal Applied and Environmental Microbiology.

" of produce seems strongly influenced by the time since the last , the workers' and the field's use prior to planting of produce," says first author Sangshin Park of Texas A&M University, College Station. "These factors, together with the role of weather in produce contamination should be the targets of future research efforts to design cost-effective strategies for control of produce contamination."

E. coli contamination of on farms in Colorado and Texas was 172 times more likely if the produce field was within 10 miles of a poultry farm, and 64 times more likely if irrigated by pond water, says Park.

As E. coli is commonly used as an indicator of fecal contamination with food-borne pathogens, the practice of hygiene—availability of portable toilets and hand-washing stations for workers in the fields —and the absence of grazing or hay production on the fields prior to planting spinach, reduced the risk seven-fold.

Other potential risk factors tested in the study included numbers of workers, farm size, organic vs. conventional production, the use of chemical fertilizers, compost, and manure, says Park. The researchers assayed 955 spinach samples from 12 farms in the two states, finding that generic E. coli was present on 63 of them (6.6 percent).

Of particular note, the researchers tested their statistical model for spinach contamination to determine how accurately it was able to pinpoint the level of contamination. "The assessment of the predictive performance of a developed statistical model is largely omitted from food safety studies," says Park. Their methodology may serve as a useful template for future investigations of contamination on farms, he says.

"Because produce is commonly consumed raw, it would be best to prevent pre-harvest contamination by food-borne pathogens all together or at least to reduce it," says Park.

Explore further: Discovery in the fight against antibiotic-resistant bacteria

More information: www.asm.org/images/Communicati… 2013/0613spinach.pdf

add to favorites email to friend print save as pdf

Related Stories

Tracing foodborne pathogens on the farm

Dec 05, 2012

(Phys.org)—In 2011, an outbreak of Listeria monocytogenes in cantaloupe led to almost 150 illnesses and 30 deaths. With a spate of recent outbreaks of such foodborne pathogens as Salmonella, Shiga toxin-producing ...

Farm Rich products recalled over E. coli fears

Mar 29, 2013

(AP)—Rich Products Corp. has announced a voluntary recall of its Farm Rich Mini Quesadillas and other Farm Rich products because of a possible contamination with E. coli bacteria.

Recommended for you

Japanese scientist resigns over stem cell scandal

18 minutes ago

A researcher embroiled in a fabrication scandal that has rocked Japan's scientific establishment said Friday she would resign after failing to reproduce results of what was once billed as a ground-breaking study on ...

'Hairclip' protein mechanism explained

13 hours ago

Research led by the Teichmann group on the Wellcome Genome Campus has identified a fundamental mechanism for controlling protein function. Published in the journal Science, the discovery has wide-ranging implications for bi ...

Discovery in the fight against antibiotic-resistant bacteria

15 hours ago

For four years, researchers at Universite catholique de Louvain have been trying to find out how bacteria can withstand antibiotics, so as to be able to attack them more effectively. These researchers now understand how one ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.