Researchers from Spain found that organic vegetables often contain bacteria. They are warning consumers who buy organic produce to be careful as they found more than 50 species of potentially harmful bacteria in samples of organic spinach and lettuce alone.
According to Study Finds, consumers are increasingly switching to organic foods to avoid potentially harmful pesticides, fertilizers, and herbicides. But the team of Spanish researchers discovered in testing their organic produce samples that these foods could be contaminated with harmful bacteria from animal and human sources instead. These bacteria could be transmitted to the veggies during the growing process, harvesting, or processing.
The team of researchers collected 17 samples of organic lettuce and spinach from local supermarkets in Valencia between November 2020 and May 2021 to conduct this preliminary investigation of free-living amoebae, or FLA’s, that could be a threat to public health. They used a special technique to identify the DNA of any bacteria living in the amoebae.
A press release from the European Congress of Clinical Microbiology & Infectious Diseases said the investigators discovered that disease-causing amoebae living on organic lettuce and spinach sheltered human pathogens like pseudomonas, salmonella, and helicobacter bacteria, which can cause serious illness.
Also, in nearly two-thirds of the samples, researchers identified a bacterium called acanthamoeba castellanii, which can cause blindness and encephalitis, says Study Finds.
“Food and food-related environments create an ideal meeting place for free-living amoebae and pathogenic bacteria,” explained Dr. Yolando Moreno, of the Universitat Politecnica de Valencia in Spain who was part of the study. “However, comparatively little is known about the occurrence and diversity of free-living amoebae on organic vegetables and their role in transmitting human pathogens.”
While experts say that more global studies are needed to ensure the safety of organic produce, Moreno’s findings show that choosing organic may not always be the safest or healthiest route.
“Contamination can arise as a consequence of treating soil with organic fertilizers such as manure and sewage sludge from irrigation water,” she says. Moreno adds that leafy greens like lettuce and spinach are particularly susceptible to this contamination because they are so close to the ground and people are less likely to cook them before eating.
“Our results also stress the need to educate the public on safe and proper handling of fresh organic vegetables before eating them fresh or slightly cooked, says Moreno.”