Concomitant uptake of antimicrobials and Salmonella in soil and into lettuce following wastewater irrigation. (February 2015)

• Record Type: Journal Article
• Authors: Sallach, J. Brett; Zhang, Yuping; Hodges, Laurie; Snow, Daniel; Li, Xu; Bartelt-Hunt, Shannon
• Is Part Of: Environmental pollution. Volume 197(2015)
• Page Start: 269
• Page End: 277
• Publication Date: 2015-02
• Subjects: Antimicrobial -- Salmonella -- Wastewater irrigation -- Uptake -- Lettuce; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2014.11.018
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: The use of wastewater for irrigation may introduce antimicrobials and human pathogens into the food supply through vegetative uptake. The objective of this study was to investigate the uptake of three antimicrobials and Salmonella in two lettuce cultivars. After repeated subirrigation with synthetic wastewater, lettuce leaves and soil were collected at three sequential harvests. The internalization frequency of Salmonella in lettuce was low. A soil horizon-influenced Salmonella concentration gradient was determined with concentrations in bottom soil 2 log CFU/g higher than in top soil. Lincomycin and sulfamethoxazole were recovered from lettuce leaves at concentrations as high as 822 ng/g and 125 ng/g fresh weight, respectively. Antimicrobial concentrations in lettuce decreased from the first to the third harvest suggesting that the plant growth rate may exceed antimicrobial uptake rates. Accumulation of antimicrobials was significantly different between cultivars demonstrating a subspecies level variation in uptake of antibiotics in lettuce. Highlights: Antimicrobial uptake in lettuce is cultivar dependent. Antimicrobial concentrations in lettuce decrease despite repeated exposure. Lincomycin is better conserved in the soil-plant system than oxytetracycline or sulfamethoxazole. Subirrigation resulted in more Salmonella in bottom soil than in top soil. Internalization frequency of Salmonella in lettuce is low despite repeated exposure. Abstract : Cultivar-specific differences in lincomycin and sulfamethazine uptake were observed in lettuce, while uptake of Salmonella was low despite repeated exposure from wastewater.