Assessing the Role Good Agricultural Practices Play in Reducing Pre-Harvest Contamination of Fresh Vegetables

Foodborne disease outbreaks caused by contaminated fresh vegetables continue to be a concern in the United States despite efforts by industry, academia and the government to reduce their incidence. Gaps, misconceptions and emerging perceptions among growers with regard to their decision-making process and practices concerning prevention of and response to pre- and post-harvest contamination were identified using responses to a mail questionnaire administered to Midwestern vegetable growers (n=621). Returned questionnaires (n=261) were coded and responses analyzed using non-parametric statistical tests. Only growers who self-reported as being very familiar with GAPs implemented them consistently (r=0.00).  In contrast, there was no significant correlation between frequency of GAP implementation, such as water quality testing and equipment sanitation (r≤0.379), and GAP familiarity among growers who claimed any lesser degree of familiarity with GAPs (r=0.437). Growers strongly or somewhat agreed that pre-harvest plant diseases and pre- and post-harvest insects were sources of microbial contamination. Respondents were unsure if transplants and post-harvest plant diseases were a source of contamination (median response was “neither agree nor disagree”).  Most growers strongly or somewhat disagreed that seeds were a source of contamination. Eminently, there is a gap in perceived knowledge between familiarity with GAPs and their actual implementation, except amongst the most knowledgeable growers. Grower’s beliefs that plant diseases can be sources of contamination warrant further studies in plant-human pathogen interactions on vegetables. These findings support the development of target-specific methods of communication and response.