What Causes Presence Of Grit-like Substance In Private Area?

the past few times i've taken a shower, while washing my private i've noticed small grit-like stuff. the first time i noticed it, i thought maybe it was dirt somehow, so i cleaned it out. but today while showering, i've noticed the same thing again. there's no itching or anything like that. i also don't think it's due to dryness. should i be concerned?