not really of course - and the high pitched singing of insects make a loud buzzing and ringing choir at the end. the black is great with a round label on top to describe the sample. if your fluoride levels are extremely low, we may recommend a fluoride supplement. the fear is gone but frustration comes and goes. you must live your truth and not be overwhelmed or afraid of the negative or the positive. this would stop any issues with the shower curtain not being able to dry out properly as it rests on the bottom of my bath. 