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glance in the mirror after finishing it will make the user think his teeth are truly white. Some manufacturers add optical whitening dyes—the stuff more commonly found
in washing machine bleach—to make extra sure that that glance in the mirror shows reassuring white.
These ingredients alone would not make a very attractive concoction. They
would stick in the tube like a sloppy white plastic lump, hard to squeeze out as well
as revolting to the touch. Few consumers would savor rubbing in a mixture of water, ground up blackboard chalk, and the whitener from latex paint first thing in the morning. To get around that finicky distaste the manufacturers have mixed in a host of other goodies.
To keep the glop from drying out, a mixture including glycerin glycol—related to the most common car antifreeze ingredient—is whipped in with the chalk and water, and to give that concoction a bit of substance (all we really have so far is wet colored chalk), a large helping is added of a gummy molecule from the seaweed Chondrus Crispus. This seaweed ooze spreads in among the chalk, paint, and antifreeze, then stretches itself in all directions to hold the whole mass together. A bit of paraffin (the fuel that flickers in camping lamps) is pumped in with it to help the moss ooze keep the whole substance smooth.
With the glycol, ooze, and paraffin we’re almost there. Only two major chemicals are left to make the refreshing, cleansing substance we know as toothpaste. The ingredients so far are fine for cleaning, but they wouldn’t make much of the satisfying foam we have come to expect in the morning brushing.
To remedy that every toothpaste on the market has a big dollop of detergent added too. You’ve seen the suds detergent will make in the washing machine. The same substance added here will duplicate that inside the mouth. It’s not particularly necessary, but it sells.
The only problem is that by itself this ingredient tastes, well, too like detergent. It’s horribly bitter and harsh. The chalk put in toothpaste is pretty foul-tasting too for that matter. It’s to get around that gustatory discomfort that the manufacturers put in the ingredient they tout perhaps most of all. This is the flavoring, and it has to be strong. Double rectified peppermint oil is used—a flavorer so powerful that chemists know better than to sniff it in the raw state in the laboratory. Menthol crystals and saccharin or other sugar simulators are added to complete the camouflage operation.
Is that it? Chalk, water, paint, seaweed, antifreeze, paraffin oil, detergent, and peppermint? Not quite. A mix like that would be irresistible to the hundreds and thousands of individual bacteria lying on the surface of even an immaculately cleaned bathroom sink. They would get in, float in the water bubbles, ingest the ooze and paraffin, maybe even spray out enzymes to break down the chalk. The result would be an uninviting mess. The way manufacturers avoid that final obstacle is by putting in something to kill the bacteria. Something good and strong is needed, something that will zap any accidentally intrudant bacteria into oblivion. And that something is formaldehyde—the disinfectant used in anatomy labs.
So it’s chalk, water, paint, seaweed, antifreeze, paraffin oil, detergent, peppermint, formaldehyde, and fluoride (which can go some way towards preserving children’s teeth)—that’s the usual mixture raised to the mouth on the toothbrush for a fresh morning’s clean. If it sounds too unfortunate, take heart. Studies show that a thorough brushing with just plain water will often do as good a job.
My Notes
Writing Workshop 3 • Expository Writing: Writing to Inform 3
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