Abstract：
Foodborne outbreaks caused by fecal contamination of fresh produce represent a serious concern to public health and the economy. As the consumption of fresh produce increases, public health officials and organizations have pushed for improvements in food safety procedures and environmental assessments to reduce the risk of contamination. Visual inspections and the establishment of \"buffer zones\" between animal feeding operations and producing fields are the current best practices for environmental assessments. However, a generalized distance guideline and visual inspections may not be enough to account for all environmental risk variables. Here, we report a baseline measurement surveying the background Bacteroidales concentration, as a quantitative fecal contamination indicator, in California\'s Salinas Valley. We collected a total of 1632 samples from two romaine lettuce commercial fields at the time of harvesting through two seasons in a year. The quantification of Bacteroidales concentration was performed using qPCR, revealing a notably low concentration (0-2.00 copies/cm2) in the commercial fields. To further enhance the applicability of our findings, we developed a user-friendly method for real-world fecal contamination risk assessment that seamlessly integrates with industry practices. Through the generation of heatmaps that visually illustrate varying risk levels across fields, this approach can identify site-specific risks and offer fresh produce stakeholders a more comprehensive understanding of their land. We anticipate this work can encourage the use of Bacteroidales in the fresh produce industry to monitor fecal contamination and prevent future foodborne outbreaks.
摘要：
由新鲜农产品的粪便污染引起的食源性暴发是公共卫生和经济的严重关切。随着新鲜农产品消费的增加，公共卫生官员和组织推动改进食品安全程序和环境评估，以降低污染风险。目视检查和在动物饲养作业和生产领域之间建立“缓冲区”是当前环境评估的最佳实践。然而,广义的距离指南和目视检查可能不足以考虑所有环境风险变量。这里,我们报告了基线测量，调查了背景拟杆菌的浓度，作为粪便污染的定量指标，在加州的萨利纳斯山谷。在一年的两个季节收获时，我们从两个生菜商业领域收集了总共1632个样品。使用qPCR进行拟杆菌浓度的定量，在商业领域显示出明显的低浓度（0-2.00拷贝/cm2）。为了进一步提高我们发现的适用性，我们开发了一种用户友好的方法，用于真实世界的粪便污染风险评估，该方法与行业实践无缝集成。通过生成热图，直观地说明不同领域的风险水平，这种方法可以识别特定地点的风险，并为新鲜农产品利益相关者提供对其土地的更全面了解。我们预计这项工作可以鼓励在新鲜农产品行业中使用拟杆菌来监测粪便污染并防止未来的食源性爆发。
