Food poisoning was not the culprit in the misery that hit fifty people who attended a weekend wedding reception in Ankeny. State public-health department spokesman Kevin Teale says they think punch got contaminated with sodium nitrite, a preservative used to cure food and keep its color, used a lot in the food industry but -not- in punch. Teale explains you’d use sodium nitrite if you were curing meat, and there are other uses outside the food industry, so it’s a common chemical, just not one you’d drink. Medical detectives from the public health department questioned dozens of people who attended the affair. The interviews kept returning to the punch, and lab tests turned up contaminants in it, while tests on other foods didn’t show they could have caused problems. Fifty people were sickened at the private party and twenty spent a night in local hospitals, but Teale says everyone is recovering.