Stores in low-income areas suffer higher risk of food contamination
Knowing that people living in low-income neighborhoods often suffer from higher rates of food borne or gastrointestinal illnesses, University of Houston researchers decided to analyze the produce Houstonians eat.
What they found: Loose-leaf romaine lettuce purchased from supermarkets in low-income Houston communities were contaminated with higher rates of disease-causing microorganisms, fecal contaminants and pathogens than lettuce purchased in high-income communities in the city.
The study by UH food safety researchers, published in the Journal of Food Protection, showed that in low-income areas, 87 percent of the lettuce samples were positive for staphylococcus aureus or staph, which can cause a range of illnesses, including skin infections, pneumonia and meningitis — particularly among those who are immunosuppressed. More than half of the samples tested positive for salmonella, 4 percent tested positive for a strain of E. coli, and 13 percent were contaminated with listeria, a bacteria that can cause fever, diarrhea and a range of symptoms that send nearly 30,000 people in the U.S. to the hospital each year, according to the Centers for Disease Control and Prevention.
Samples collected from the high socioeconomic status areas, however, showed far less contamina
“A significant issue exists, and further investigation is needed to identify where this disparity begins in the supply chain.” Sujata Sirsat, lead study author and assistant professor at the UH Conrad N. Hilton College of Hotel and Restaurant Management
tion. Staph was the only harmful microorganism found in just 38 percent of the lettuce samples from higher-income areas, according to the study.
“A significant issue exists, and further investigation is needed to identify where this disparity begins in the supply chain,” Sujata Sirsat, lead study author and assistant professor at the UH Conrad N. Hilton College of Hotel and Restaurant Management, said in a written statement. “It’s a big, big problem. We shouldn’t see this type of empirical evidence.”
The researchers, which include UH post-doctoral fellow Zahra Mohammad and undergraduate student Isabella Raschke, purchased the lettuce samples from five stores in high-income neighborhoods and five stores in low-income neighborhoods in Houston at the same times between June and December 2020 using the U.S. Department of Agriculture Economic Research Service Food Access Research Atlas and the U.S. Census Bureau’s definitions of high and low income statuses.
The study focused on leafy greens, the produce most associated with foodborne illnesses, and was conducted three different times during that period using testing for pathogen contamination.
While the results cannot pinpoint the exact problem within the supply chain, researchers say findings could suggest that there are issues with personal hygiene, cross contamination and time temperature abuse within stores in poorer areas. Sirsat said that these results could send a negative message to people living in those areas or food deserts in the city, which lack supermarkets with fresh produce but are often overwhelmed with fast food restaurants that offer inexpensive, calorie-dense and unhealthy food options that can lead to chronic health conditions.
“You’re essentially telling people in low-income areas that it’s safer to eat processed foods and risk longterm chronic health conditions rather than eating fresh produce and improving their health,” Sirsat said. But the researchers wrote “where someone lives should not affect their access to safe, high quality, and nutritious foods.”
The hope is that the study’s findings will help increase the understanding of why disparities within the food industry exist and how systemic and policy changes can help improve access to safe and healthy produce.
“We need to educate the retail industry about this issue, so they understand certain practices need to be in place to keep the produce safe,” Mohammad said in a statement. “We have to find out why this is happening.”