If you had any amount of confirmed mycotoxins in your grain at harvest, it is safer to avoid storing the affected grain.
Ambient temperatures will be getting warmer and soon will be above 40°F, which is about the temperature where fungal (mold) spores begin to grow again in the spring. If the fungal organism is one that produces mycotoxins, the level of mycotoxins in the grain can increase, which will likely result in greater dock when the grain is sold.
The worst case would be if the grain were refused by the grain dealer or not approved for feeding to certain species or sizes of livestock.
Disinfecting Empty Bins and Harvest Equipment
It is important to thoroughly clean out bins once they are empty, including all grain and grain dust that could still contain molds and insects. When moldy grain has been removed from the bin, use a spray disinfectant on all interior surfaces to kill mold spores. A solution of 1 gallon of 5.25% household laundry bleach and 20 gallons of water should work well. Several days after applying the bleach, rinse it off so as not to corrode galvanized metal.
Source: Cropwatch.unl.edu