Hilchos Issurei Mizbeiach 6:13

If kernels of wheat were picked from cattle dung and planted, there is a doubt as to whether their repulsive nature is changed through planting. Therefore, one should not bring an offering from such flour, but if one did so, it is fit.

Hilchos Issurei Mizbeiach 6:14

The following oils are unfit for the altar: oil from olives that were soaked in water or pickled, of cooked olives, of olive dregs, and with an offensive smell. These are unfit, but if olives were planted in a trash heap, in an arid field, or had another crop planted in between them, or if oil was made from unripened olives –these oils should not be brought on the altar, but if they were brought, they are fit.