Wheat, rice, and flour often have little teeny bug eggs in 'em; can't really be helped. This is why, when you bring home these items, you stick 'em in the freezer for 3-4-5 days; it kills any nits.
Then, take whatever it is out of the freezer and put it on the counter to defrost and dry out. Just keep rotating the bag until it doesn't feel cool anymore. After that, you can section it up and store it.
This is what we do anyway and haven't yet had bug problems.
Recently came home with a 25-lb bag of Jasmine rice and Gunsmith had doubts I could fit it in the freezer. I love a good challenge.