Yes, the bucket will crack from a combination of weather and UV degradation long before dangerous levels of "whatever" are likely to leach into the water. Actually, removal of some of those dangerous over very long period and in high dosage chemicals, such as Bisphenol A (BPA), tends to make the bucket more brittle, less "plastic" (as in, maleable and able to have its shape deformed without failure) than they used to be. and thereby helping to fill landfills faster witht he rest of the materials that make up that bucket.
and still safer than galvanized steel.
Oh, and the chemicals which make the bucket Home Depot Orange provide *slightly* more UV resistance than the Blue for a Lowes' bucket, for reasons I don't understand, but I don't know if the relative amounts of them more than compensate. I seem to remember HD buckets being "more orange" in my youth, while the Lowes buckets remain pretty blue.
Finally, I just bought a new Lowes bucket last week (my closest Home Dpot is almost 60 miles away). Flip it over, and its "HDPE 2" in a triangle. High Density Polyethylene "2" - that's stable food grade plastic. One of the more stable, actually. Your Home Depot buckets may say the same.