Everybody worries about the health risks from the different blasting media. No matter which media you use, the stuff you're blasting off (paint, lead, rust, asbestos, petroleum products, etc) are all health risks so you just have to protect yourself. Personally, I stick with sand because of the cost of the other stuff.
I have an old 1300 gallon plastic water tank with a door opening cut in it and a barn ventilating fan on the top hole for ventilation. I put the parts in the tank and I sit outside doing the blasting. There's enough air rushing in the doorway that I don't get any dust but I still wear a dust mask to be on the safe side. Using that tank saves the sand but the dust all blows away so you can keep reusing the sand. Without the fan removing the dust you can only reuse the sand a few times and it becomes so dusty that there's no visibility.
You need a minimum 5 HP compressor and 7 or 10 is even better. You have to maintain close to 100 PSI or it gets to be a slow process. I've blasted aluminum with sand and it cleans it up good but leaves a dull finish. You just have to hold the nozzle farther away or you could get some gouging so take it easy.