Overview of pre- and post-harvest practices leading to microbial and chemical contamination of peanuts in Benin

Abstract

In Benin, pre- and post-harvest peanut practices could lead to chemical and microbial contamination of peanuts and their products. This study outlines local farming practices that may contribute to microbiological and chemical contamination of peanuts. Based on 395 individual interviews, the study was conducted in five municipalities of Southern Benin. Results showed that 95.0% of farmers use uncertified seeds, from previous harvests. Peanuts were grown either as monocultures (66.0%) or intercropped (34.0%), especially with over half respondents (53.0%) applying unapproved pesticides (83.3%), mainly glyphosate-based products, obtained formally. After harvest, 58.0% of farmers dried their seeds in two steps: unshelled before storage (100.0%) in reused polypropylene bags (76.0%) placed directly on the ground. The use of unapproved pesticides may lead to chemical contamination of peanuts through residues of toxic substances such as glyphosate and lambda-cyhalothrin. Moreover, inadequate drying and storage in polypropylene bags promote mould growth, particularly Aspergillus species, and subsequent aflatoxins production. Such contaminations could compromise peanuts sanitary quality and pose significant food safety challenges. These observations highlight a potential public health concern. Therefore, identified risks should be assessed and managed for producing and processing safe peanuts in Benin.