Parasitic contamination of fruit and vegetable products
Authors:   FSBEI HE Astrakhan State Medical University of the Ministry of Health of Russia, parasitologist of the Center for Hygiene and Epidemiology in the Astrakhan Region, Astrakhan, Russia,, Arakelyan Rudolf Sergeevich , Stepanenko Elizaveta Aleksandrovna ,   FSBEI HE Astrakhan State Technical University, Astrakhan, Russia
Published: May 2022

The purpose of the study. To investigate and analyze the parasitic and microbiological contamination of fruit and vegetable products grown and sold on the territory of the Astrakhan Region. Materials and methods. 4,792 food samples were analyzed, 7,776 studies were performed. The share of fruit and vegetable products in the structure of all food products was 62.3 % (n=2,984), of which 2.8 % (n=84) did not meet the norm. The results of the study. In most cases, vegetable products were delivered to the research — 85.7 % (n=2,559), represented by 23 species. The number of samples that did not meet sanitary and parasitological indicators was 2.4 % (n=62), of which the majority, i.e. 90.4 % (n=56) of all positive findings among vegetables, were dead Strongyloides stercoralis larvae, 1.6 % (n=1) were live Strongyloides stercoralis larvae, Toxocara canis and Opisthorchis felineus eggs, Entamoeba histolytica cysts, as well as mixed infections: fertilized eggs of Ascaris lumbricoides + dead larvae of Strongyloides stercoralis and unfertilized eggs of Ascaris lumbricoides + dead larvae of Strongyloides stercoralis. In addition to vegetable products, fruits (3.5 % (n=106) — Figure 2) were delivered to the study. The number of fruit samples that did not meet parasitological indicators was 1.9 % (n=2). Dead larvae of Strongyloides stercoralis were found in all samples. Also, the studies of parasitic contamination of berry products were conducted which accounted for 5.3 % (n=159), represented by 13 species. The percentage of unsatisfactory samples was 4.4 % (n=7): dead Strongyloides stercoralis larvae were found in 57.2 % (n=4), Opisthorchis felineus eggs — in 28.6 % (n=2) and mixed infections (Toxocara canis eggs + dead Strongyloides stercoralis larva) — in 14.2 % (n=1). Finally, the samples of table greens were delivered to the laboratory for research accounting for 5.2 % (n=155), of which 4.5 % (n=7) did not meet the hygiene standards: dead larvae of Strongyloides stercoralis and eggs of Enterobius vermicularis were found in 85.7 % (n=6) and 14.3 % (n=1), accordingly. Conclusions. Positive findings (helminth eggs and larvae) were more often found in the samples of fruit and vegetable products and table greens that had direct contact with the ground. The presence of positive findings in the samples of fruit and vegetable products indicates the contamination of these products with feces of infected animals (dead larvae of Strongyloides stercoralis and eggs of Toxocara canis) and humans (eggs of Opisthorchis felineus, Ascaris lumbricoides, and Enterobius vermicularis and cysts of Entamoeba histolytica). The presence of helminth eggs (Opisthorchis felineus, Ascaris lumbricoides and Enterobius vermicularis eggs) and cysts of pathogenic intestinal protozoa (Entamoeba histolytica) indicates the contamination of manure with feces of infected people. The presence of dead Strongyloides stercoralis larvae in the studied apple samples indicates that the soil was contaminated with the feces of infected animals, as well as that these samples were taken directly from the contaminated soil, not from the tree. According to microbiological indicators, the studied samples met the safety requirements. Coliform bacteria and pathogenic microorganisms were not detected. QMA&OAMO, yeast and molds are within the permissible limits of 1×10⁴ (for QMA&OAMO), 1×10² (for molds and yeast).