PhD Oral Defense: Assessment of irrigation water quality for the Quebec horticulture industry
PhD Oral Defense of Divya Gupta, Department of Bioresource Engineering
Ready-to-eat vegetables when irrigated with untreated surface water cause risk of gastrointestinal infection to humans. Greenhouse and field studies were conducted to quantify Escherichia coli in the irrigation water and vegetables irrigated with untreated water. The Quantitative Microbial Risk Assessment (QMRA) model used data from the greenhouse and field studies to estimate the health risk to humans on the consumption of irrigated fresh fruits and vegetables. The field study analyzed pathogenic E. coli in the irrigation water during the May-October growing seasons in 2013 and 2014 from two field sites, St-Remi and Rougemont in Quebec. In Rougemont, the maximum concentration of E. coli was found during the May-June period for both years. Whereas in St-Remi, the maximum E. coli concentration was found during the May-June and the September-October. The greenhouse study was conducted in controlled environmental conditions at the Macdonald campus to confirm the level of contamination that was transferred to fruits and soil over a 30 days’ time period.