Reference for Chullin 211:8
אתא רב דימי אפקה אתא רבין קטלה
and the omission to wash after the meal caused a murder.<span class="x" onmousemove="('comment',' V. Yoma 83b, where it is related that certain Rabbis had entrusted their purses to a certain man who later denied all knowledge of them. They noticed that the man had traces of lentils on his upper lip, so they immediately went off to his home and asked his wife in the name of her husband to hand them the purses. On her asking them to prove their bona fides they told her that her husband had eaten lentils that day. She thereupon handed them the purses. When the husband came home and learnt what his wife had done he immediately divorced her, or as some say, killed her. Now had the husband been particular about washing the hands (and naturally also the lips) after the meal, this tragedy of a divorce or a murder would not have happened.');"><sup>2</sup></span>