Hi. Thanks for your query. Noted your history of small white particle comes out on sneezing. When you observe it, it looks white in color, about the size of a mustard seed, and has an odor. Sometimes multiple of these particles come out but very, very small and wants to know what they are. These particles may be the inspissated mucus and nothing more than this. This can be easily diagnosed by nasal Endoscopy by an ENT Surgeon and once everything is said to be normal, you do not need any treatment for this apparently normal looking thing. But if he finds something positive, please get treated according to his findings.