Aflatoxins are naturally occurring carcinogens found on grains, particularly in warmer climates. Because of their carcinogenic properties, they are strictly regulated and are only allowed in minimal amounts. Aflatoxin B1, the most potent naturally occurring carcinogen known, is metabolized in the liver to form aflatoxin M1, which is present in the milk of lactating animals. If aflatoxin concentrations are elevated above legal limits, the milk cannot be used for human consumption. Because of this, research has been conducted to evaluate ways to mitigate its absorption in the animal and prevent transfer to the milk. One such way is through the use of clay adsorbents. The current studies aimed to evaluate the efficacy of two different clay adsorbents at preventing aflatoxin transfer to the milk of Holsteins fed a known concentration of aflatoxin.