Aflatoxins are a group of toxic fungal metabolites produced by Aspergillus flavus and other molds. Aflatoxins can lead to cancer and deaths in humans and animals. Grains and oilseed crops contaminated with aflatoxins often must be destroyed. Of the 16 naturally occurring aflatoxins, aflatoxin B1, B2, G1, and G2 are commonly detected in food and feedstuffs. Of the common aflatoxins, B1 is the most toxic. Montmorillonite is commonly added to animal feeds to form pellets and to improve flow characteristics. As an added benefit, montmorillonite has been shown to adsorb aflatoxins and reduce the toxicity to animals. In this study, the retention of aflatoxin B1 (AfB1) by clays has been measured using batch adsorption isotherms and by directly mixing with AfB1-contaminated corn meal. Enzyme-linked immunoassay and UV absorption methods were used to measure AfB1 concentrations. Batch adsorption isotherms indicated that the reference montmorillonites, SWy-2 and SAz-1, were more effective than Novasil, but some hydrotalcite-like synthetic minerals were more effective than montmorillonites. Corn meal samples contaminated with ~900 µg AfB1/kg were mixed with 2% clay and later extracted with 60% methanol/40% 2M NaCl. The untreated corn meal extract contained 865 µg AfB1/kg. Addition of 2% hydrotalcite, SWy-2, SAz-1, and Novasil to the corn meal, respectively, reduced the extract concentrations to 86, 101, 109, and 174 µg AfB1/kg.