Clothes Have a Blue Tint After Washing

Are you using bleach in your wash? This wreaks havoc on any whites that aren't 100% cotton. Try putting some baking soda along with detergent in with your whites next time. You will see your whites the whitest ever! I learned this from my 89 year old Aunt whose white undies were so white all the time.

Most likely the cause is dye bleeding out of a colored item in the wash. If you're washing the whites with absolutely nothing but whites, tell us what kind of washer, detergent, additives, dryer, etc., you are using.