1 In general, the total dissolved solids concentration is the sum of the cations (positively charged) and anions (negatively charged) ions in the water.  Parts per Million (ppm) is the weight-to-weight ratio of any ion to water.
If you refrigerate the rice, and you want to eat it cold, its perfectly fine. People eat cold rice salads all the time. Cold rice pudding is fine. Its just sitting around at room temperature that is the problem.
1 If left out for more than 45 minutes, don't eat it or you'll get food poisoning.  Yes, eating uncooked rice is bad for you. I've had an experience with eating uncooked rice and I guess I just got addicted to the taste. I kept eating it and eating it, until my blood level just dropped.