grown and organically grown samples, which also possessed thermotolerant coliforms above the recommended
levels in 66% and 80% of samples, respectively. Salmonella sp. was not detected in any of the
analyzed samples. Traditionally grown and organically grown samples also exhibited a high frequency of
intestinal parasites, including the pathogenic Taenia sp. and the Entamoeba histolytica species. In contrast,
only 20% of hydroponically grown lettuce samples were contaminated with parasites. Sodium hypochlorite
and acetic acid at concentrations of 100 mg L1 and 1%, respectively, were effective in reducing
bacterial counts, even in samples with high levels of contamination.