Mycotoxins have become a major concern for health and economic problems all over the world particularly in the tropical countries. These countries, in particular are experiencing hazard exposure to mycotoxins. The aim of the study was to assess the effects of mycotoxin incidences in maize and groundnuts on household food safety in Kilosa District. Storage practices and weather variables (temperature, rainfall and relative humidity) were examined on their influence on mycotoxin contaminations. Eighteen samples of maize and groundnuts per household were collected from farmers in four villages. Weather variables were collected using data loggers. Aflatoxins and fumonisins analyses were done by the high performance liquid chromatography (HPLC) method. Log-linear model was used in estimating effect of weather variables. Ordinal logistic regression analyses were performed to predict the contribution of socio-demographic and socio-economic factors on the knowledge level of mouldy infections among respondents. Furthermore, multiple regression models were used in the analysis of factors contributing to mycotoxins production. The t-test, ANOVA and Chi-square tests were used to test the significance of relationships across variables. The levels of aflatoxins and fumonisins in all samples collected were 20 pg/kg, which is the US Food and Drugs Authority regulatory level destined for use in human food. A significant difference (p< 0.05) existed between samples which were collected at different agroecological zones. Fumonisin concentration was significantly higher when maize had been stored in terms of heaps on a floor in a house (179.54 pg/kg) and lower levels of fumonisins were recorded when maize was stored in the crib (135.91 pg/kg). Fumonisin Bi and aflatoxin Bi were found to increase over the storage period and were significant (p<0.05). There were highly significant (p<0.001) effects of temperature, relative humidity and rainfall on the production of mycotoxins in stored maize. Roughly, one-fifth of maize produced for human consumption in the study area is lost through fungal spoilage and this loss amounted to about 4331 tons per year. Most of the respondents had low level of knowledge regarding mouldy infection in stored crop products. Strategic interventions such as sorting, proper drying, proper storage and insect management to curtail mycotoxin contamination should be directed towards improved postharvest practices of maize and groundnuts to avoid food spoilage.Dr. Martin Kimanya of TFDA