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.
Q: Is it okay to leave cooked rice at room temperature? A: It's safest to serve or refrigerate rice within a few hours of cooking. Though rice is an infrequent cause of illness, several outÂ­breaks have been reported over the years, typically linked to rice that was left out overÂ­night in restaurants. Because the illness tends to be mild, many cases go unreported. Uncooked rice is often contaminated with Bacillus cereus bacteria from soil.