Understanding which environmental factors are favorable to the presence or spread of foodborne pathogens in growing areas is important to achieving food safety. It enables regulatory officials and industry groups to refine guidance on best practices for growers, so they may continually improve the safety of their products. It is also an area in which there is still much to be learned.
Toward this goal, FDA sometimes conducts multi-year environmental studies that are designed to shed light on environmental conditions that could impact food safety. The regions selected for study typically grow produce that is consumed raw or with minimal processing. In some instances, recurring foodborne illness outbreaks may have been linked to the region. Other times the region may not have links to recurring outbreaks, but a better understanding of the ecology and growing conditions could offer insight as to why there are fewer or no outbreaks linked to the region.
Factors that are studied may include, but are not limited to:
- sources of irrigation water and types of irrigation
- surface water sediment
- soil and soil amendments
- topography of the growing region
- proximity of growing areas to livestock, animal feeding operations, and wildlife
- location of the agricultural operation relative to wildlife migratory patterns
- wind speed and direction, especially as it relates nearby agricultural operations
- water runoff through the growing area
- temperature, rainfall, fog, dew
- native flora surrounding the growing area
- airborne particulate
- whether or not current best practices are being followed on a farm
Through repeated observation, data collection, sampling, and testing, researchers can identify sources of foodborne pathogens endemic to the environment, better understand the conditions under which they persist, and determine the vectors by which the pathogens move through the environment.
These studies are usually collaborative efforts by FDA, state and local public health officials, academia, and members of the produce industry.
Examples of current and past environmental studies include:
- Yuma Agricultural Region Environmental Microbiology Study, 2019 – present
- Delmarva Produce Safety Environmental Research Study, 2009 – 2014
Information about environmental assessments, which in contrast to environmental studies look at conditions on individual farms immediately after the farm is associated with an outbreaks, can be found on FDA’s Environmental Assessments from Foodborne Illness or Contamination Events web page.