EFFECTS OF SOURCES OF IRRIGATION WATER AND PESTICIDES ON POSTHARVEST QUALITY OF THREE VEGETABLES IN THE WA MUNICIPALITY OF THE UPPER WEST REGION OF GHANA

The objectives of the study were to document sources of irrigation water, microbial load in the water and in vegetables, pesticides used and its residue in produce and postharvest treatments applied to produce. A survey and laboratory experiments were used in the study. One hundred (100) respondents were interviewed and the data analysed using SPSS 19. Data of microbial content and pesticides residue in produce were analysed using Statistix 9. Major source of irrigation water for vegetable production was dug out well (88%). Watering cans and buckets were the common aids for irrigation (82%) adopted during the dry season vegetable farming. Cypermethrin, dichlorodiphenyl trichloroethene (DDT), Lamda and Actelic 25 EC were the most common pesticides used in controlling pests and diseases. The major postharvest treatment applied to the produce was washing of vegetables in salted water (45%). Consumption of contaminated vegetables, resulted in, stomach ache (77.5%) and diarrhea (22.5%). Laboratory analysis of water for irrigation and the vegetables produced thereof, indicated the presence of total coliforms, faecal coliforms, E. coli and Salmonella. Heptachlor, Alpha Endosulfan, Endrin, 1,1-dichloro-2, 2-bis(4-chlorophenyl) ethylene (PP-DDE), 1,1,1-dichlo-2,2-bis (4-chlorophenyl) ethane (PP-DDT) and Permethrin were pesticides residues found exceeding the International Maximum Residue Level (MRL) allowed in vegetables.