Try adding some vinegar in the water or baking soda - these will usually get rid of odors.
In the early days of the sanctions, dual use items included everything from baking soda to truck tires.
If you use a dry diaper pail, adding a few drops or tea tree or lavender oils or placing dryer sheets or baking soda into the pail can cut down on the odor.
The cat litter product line is of interest because Arm and Hammer has integrated its baking soda into cat litter to mitigate cat box odors.
It is formulated with a proprietary blend of biodegradable corn fibers and baking soda.