Feces doesn’t seem to be on the zooplankton menu. These small aquatic animals are known to eat other bacteria, but a new study shows that they do not “clean” freshwater or seawater by eating fecal microbes in contaminated seawater. Masu.20. For details of the survey results, please see The study was published Oct. 3 in the journal Biology millisphere.
Water from sewage or septic tanks can accidentally enter freshwater bodies due to improper water treatment. corroded infrastructure, rainwater runoffand an accident. This contamination can cause illness when humans and other animals come into contact with it. a 2017 US Water Quality Inventory revealed that more than half of the country’s rivers, bays and estuaries are considered unsafe for at least one use, and that some of these cases are due to fecal contamination.
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“When sewage is released into clean bodies of water and humans are exposed to it, it can lead to human disease,” said study co-author Lauren Kennedy, a civil engineer at the University of Texas at El Paso. stated in a statement. “Our research aims to understand what factors prevent pathogens from being able to infect humans. In other words, how long will water be safe for recreation again without outside intervention? Does it cost?”
The research team hypothesized that zooplankton may play a role in purifying polluted water. These microorganisms are naturally present in water, and fecal contamination can feed on them. This inactivates dangerous microorganisms and “purifies” the water.
in studythey added A virus called MS2 and bacteria Escherichia coli Freshwater and saltwater samples collected from the San Francisco Bay area. According to Kennedy, both the virus MS2 and bacteria Escherichia coli They are typically found in high concentrations in sewage and are therefore considered useful surrogates for scientific research. Their presence usually indicates that there is fecal contamination in the environment. The water samples used by the research team naturally contained both large particles, such as zooplankton, sand, and soil, as well as smaller or dissolved particles, such as salt.
Large particles containing zooplanktonThere appeared to be no significant effect. MS2 inactivation and Escherichia coli Pathogen surrogate in water. In fact, it was these smaller articles that had the bigger impact. Both added viruses and bacteria were inactivated at higher rates in highly saline waters, such as seawater taken from San Pedro Beach.
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This study has given scientists a new understanding of some of the limitations of using zooplankton as a natural method to purify contaminated water. in Follow-up surveythe research team will focus on the effects of salinity on pathogens that survive in contaminated water.
“I’m proud to be able to provide a new perspective on surface water cleanup efforts,” Kennedy said.
