Food Safety Report: Natural Grocers, South 3rd Street West, Missoula, MT, USA 2 years ago • details 10 Comments Comment Suspected food poisoning. Symptoms: Diarrhea, Nausea, Vomiting, Cramps Suspected source: Romaine lettuce Onset: Less than 4 hours Duration: 4 to 12 hours Sick: 2 people