I would not include Iodine 131 as a risk, since it has an 8 day half-life, which means that it is 99% gone in 60 days. And it is found usually in materials used for medical imaging/therapy or in material thrown out from a nuclear reactor event.
Radium, on the other hand, is naturally occurring. And there's a lot of it in some regions. Ra 226 has a half-life of 1600 years and Ra 228 has a half-life of 5.76 years. They will be around for some time, and give off enough radioactivity that they are considered health hazards. There are maps of where this is found in the US and probably the world, so you could easily figure out the chance of it contaminating your raw materials. And if you use water in your processing, you can find out how much is in your water and remove it with a water treatment system.
Uranium 238 is naturally occurring, and abundant, but the radiation is very weak. It would not be good to have in your materials, but I would not be highly concerned. Uranium 235 is weapons grade, and is not abundant, so I would think that it is not likely for it to contaminate materials.
Strontium 90 and Cesium 137 are products of fission, so they should be considered if your materials originate from an area where there was a nuclear reactor event, like Chernobyl or Fukushima Daiichi or from old nuclear test sites.
In case people are worried about irradiation of materials to kill bacteria leaving "residual radioactivity" in the product, that does not happen. The radioactivity that is used to expose materials to kill pathogens is not put into the material, but energy from the radioactivity is used to expose the materials. it's like shining a light on it, just a light that penetrates and kills.
And now for some things that are a little
Stuff that has been irradiated does not glow in the dark, but some materials that contain radioactivity glow in UV light, like uranium glass.
Before World War II Fiesta dinnerware used uranium in some of the glazes, and are still radioactive. The radioactivity (alpha particles) is absorbed by the air within the first inch or so, but there is the risk of it leaching into food, so it is not recommended to use nowadays. I don't think it's used anymore to make food, so you probably don't have to include it in your risk assessment.
Radioactivity is a fun topic. We are very afraid of it, but I'm more cautious about having a lot of medical x-rays and CAT scans than coming in contact with environmental radioactivity.
Martha, former Radiation Safety Officer