Guévremont Evelyne, Lamoureux Lisyanne, Généreux Mylène, Côté Caroline
1 Agriculture and Agri-Food Canada, Saint-Hyacinthe Research and Development Centre, 3600 Casavant Boulevard West, Saint-Hyacinthe, Quebec, Canada J2S 8E3; and.
2 Research and Development Institute for the Agri-Environment, 335 Vingt-cinq Road East, Saint-Bruno-de-Montarville, Quebec, Canada J3V 0G7.
J Food Prot. 2017 Jul;80(7):1182-1187. doi: 10.4315/0362-028X.JFP-16-551.
Irrigation water has been identified as a possible source of vegetable contamination by foodborne pathogens. Risk management for pathogens such as Campylobacter spp. and Listeria monocytogenes in fields can be influenced by the source of the irrigation water and the time interval between last irrigation and harvest. Plots of romaine lettuce were irrigated with manure-contaminated water or aerated pond water 21, 7, or 3 days prior to harvesting, and water and muck soil samples were collected at each irrigation treatment. Lettuce samples were collected at the end of the trials. The samples were tested for the presence of Campylobacter spp. and L. monocytogenes. Campylobacter coli was isolated from 33% of hog manure samples (n = 9) and from 11% of the contaminated water samples (n = 27), but no lettuce samples were positive (n = 288). L. monocytogenes was not found in manure, and only one sample of manure-contaminated irrigation water (n = 27) and one lettuce sample (n = 288) were positive. No Campylobacter or L. monocytogenes was recovered from the soil samples (n = 288). Because of the low incidence of pathogens, it was not possible to link the contamination of either soil or lettuce with the type of irrigation water. Nevertheless, experimental field trials mimicking real conditions provide new insights into the survival of two significant foodborne pathogens on romaine lettuce.
灌溉水已被确定为食源性病原体污染蔬菜的一个可能来源。田间弯曲杆菌属和单核细胞增生李斯特菌等病原体的风险管理可能会受到灌溉水来源以及上次灌溉与收获之间的时间间隔的影响。在收获前21天、7天或3天，用受粪便污染的水或曝气池塘水灌溉长叶莴苣地块，并在每次灌溉处理时采集水样和腐殖土样。在试验结束时采集莴苣样品。对样品进行弯曲杆菌属和单核细胞增生李斯特菌检测。从33%的猪粪样品（n = 9）和11%的污染水样（n = 27）中分离出空肠弯曲菌，但没有莴苣样品呈阳性（n = 288）。在粪便中未发现单核细胞增生李斯特菌，仅一份受粪便污染的灌溉水样（n = 27）和一份莴苣样品（n = 288）呈阳性。从土壤样品（n = 288）中未检出弯曲杆菌或单核细胞增生李斯特菌。由于病原体的发生率较低，无法将土壤或莴苣的污染与灌溉水类型联系起来。尽管如此，模拟实际情况的田间试验为两种重要食源性病原体在长叶莴苣上的存活提供了新的见解。
