Evaluation of the Effect of Wastewater Irrigation on the Microbiological Quality of Vegetables in Northeast Ethiopia: Implication for Food-Borne Infection and Intoxications.

BACKGROUND

Cultivation of vegetables using untreated wastewater is a common phenomenon in many drought-prone areas of the world. Consumption of such microbiologically unsafe vegetable increase the risk of food-borne diseases. As a result, evaluating the effect of wastewater irrigation on the microbiological quality of vegetables would be beneficial to consumers' health.

METHOD

A total of 192 vegetable samples (lettuce, cabbage, carrot, and tomato) and 64 irrigation water samples were collected and analyzed for total bacteria and coliform count using a standardized protocol over a 4 month period. One-way analysis of variance and Pearson correlation coefficient was used to analyze the data. Statistical significance was defined at a -value of less than 0.05.

RESULT

Carrots were the least polluted vegetable, according to the study, while cabbage had the highest contamination levels. The mean bacterial count among the vegetables differs significantly ( < 0.05). The fecal coliform counts of the irrigation wastewater exceed the international wastewater irrigation standards. The mean microbial count between vegetables and water samples showed a significant positive relationship ( < 0.05). All of the analyzed vegetable samples were of borderline microbial quality for fecal coliform bacteria.

CONCLUSION

Irrigation wastewater has a low microbiological quality, which significantly contributes to the contamination of vegetables grown on it.

RECOMMENDATION

Measures should be taken to improve the microbial quality of wastewater as well as the quality of vegetables grown in order to protect consumers' health from food-borne diseases.