Many otherwise stable explosive materials can become sensitive with age or if they make contact with incompatible materials due to the deterioration of their immediate containers. Such items may not only become more sensitive to impact but are also liable to spontaneous initiation, especially in the case of old or badly stored propellants.

http://www.free-from-explosives.com.au/

http://www.aeragon.com/o/me/

Some materials, especially WATER, will greatly accelerate deterioration of explosive. Leaky old shells become EXTREMELY sensitive to mechanical handling and changes of temperature.

People who handle deteriorated explosives are not going to live very long.