Bottles of di-tert-butyl dicarbonate buildup of internal pressure in sealed containers caused by its slow decomposition to di-tert-butyl carbonate and ultimately tert-butanol and CO in the presence of moisture. For this reason, it is usually sold and stored in plastic bottles rather than glass ones.
The main hazard of the reagent is its inhalational toxicity. Its median lethal concentration of 100 mg/m over 4 hours in rats is comparable to that of phosgene (49 mg/m over 50 min in rats).