Rawhide Dog Chews - Dogs Vomiting Blood and Diarrhea from rawhide bones

I was very cautious after the pet food recall in 2007, taking care to cook chicken and rice for both my dogs, and giving them sweet potato treats...but 3 years later, I bought them a tiny pack of "4pk triple treat bones" from drsfosterandsmith.com and now, I've been dealing with vomiting with blood, massive diarrhea from both of them. I searched around online and read that rawhide dog treats are often treated with arsenic as a preservative...what is wrong with these companies?