From the Magazine | Eating Smart
Is Teflon Risky?
Nonstick pots can emit nasty stuff if used incorrectly
By MICHAEL D. LEMONICK
Posted Sunday, Jun 11, 2006
The amazingly slippery, heat-resistant plastic known as Teflon was discovered purely by accident by DuPont chemist Roy Plunkett in 1938. By 1950, the company was making a million pounds annually as a low-friction coating for bearings and gears. In 1960 the U.S. Food and Drug Administration approved it for use in cookware. Today some 60% of all pots and pans in American kitchens are nonstick--to say nothing of muffin pans, cookie sheets, cake pans, deep fryers and waffle irons.
Unfortunately, it turns out that when Teflon is heated to over 600°, the coating can break down and release a chemical called perfluorooctanoic acid, or PFOA. The fumes can be fatal to pet birds. In humans, DuPont acknowledges, they can cause a reversible flulike condition called polymer-fume fever, first noted in the company's labs. In animals, though, PFOA can cause cancer, immune-system damage and death. And about 95% of all Americans have traces of PFOA in their blood.
No study has proved that cooking with Teflon is harmful to humans. But DuPont paid $107.6 million in 2004 to settle a lawsuit brought by some 50,000 people who lived along the Ohio River near its West Virginia plant. They claimed PFOA contamination had caused birth defects and other health problems. The company admitted no liability but in December 2005 made a settlement with the EPA based on eight violations for failing to disclose its own findings on the safety of PFOA. This April, hearings began in a class action against the company by nonstick-cookware users from 15 states. In January, an EPA advisory board labeled PFOA a likely human carcinogen.
The EPA has since asked DuPont and seven other companies that use PFOA to phase out the chemical. Although DuPont disputes the classification as a carcinogen and won't stop making Teflon, the company has pledged that by 2015, it will reduce the amount of PFOA used to make the coating and will guarantee that the chemical won't be released into the environment from DuPont manufacturing plants.
Yet in spite of all this, the agency website says, "At the present time, EPA does not believe there is any reason for consumers to stop using any consumer or industrial related products that contain PFOA." That's under normal use. You should not heat an empty nonstick pan to high temperatures or risk destabilizing the surface by plunging a hot pan into cold water, nor should you use nonstick pans for cooking at very high temperatures in general.
While nonstick cooking offers big benefits--ease of cleanup, drastically reduced need for oil--nobody has yet invented a coating that works as well as Teflon. But there's a low-tech solution that dates back hundreds of years: a good cast-iron skillet. It's cheaper than a coated pan, it browns food better, and as for the nonstick factor, when properly seasoned, it's nearly as good.
With Reported by Lisa McLaughlin/ New York
From the Jun. 12, 2006 issue of TIME magazine
Using Mikes for Speaking and Singing
The microphone is the most frequently-used audio device in the church -- and the most frequently misused, also. Here are a few tips to help you avoid some of the more common problems.
Popping
The most common problem is acoustic popping. This is caused when a puff of air from your mouth hits the diaphragm inside the mike. In normal speech, the initial consonants B and P cause what speech clinicians call "plosives." They cause a puff of air to leave the mouth. The corrective action is simple: mike distance and angle. If you hear a pop while speaking or singing, hold the mike a little farther from your mouth, and slightly below your airstream. If you're at the pulpit, step back a half step.
The result of a pop will be heard in the speaker as a dull thud. or as high breaking sound
Warning: The engineer in the sound booth cannot take corrective action if there is popping. You must make the correction by changing the distance and/or angle at the mike!
Distance
In general, a handheld mike should be no closer to your mouth than the width of your closed fist and no farther from your mouth than the distance from the tip of your thumb to the tip of your little finger, when your hand is spread.
Singing usually requires less amplification than speaking, so hold the mike a little closer for speaking.
Angle
The tip of the mike should be a little below the airstream of your voice to help prevent popping.
Appearance
A mike can detract from your appearance when held too close. If your mike has a yellow windscreen, the view from the floor level where the congregation is sitting may make it look like you're eating a lemon sherbet cone.
Distortion
In addition to popping, poor mike technique can cause distortion. This makes the sound heavy and blurred. This cannot be corrected in the sound booth. The engineer can only turn down the level, so the distorted sound won't be as loud. However, the distortion will still remain. You've probably heard plenty of distortion at a restaurant that calls diners to their available table over a handheld mike.
Mixing
When two or more people are singing together, all persons should keep about the same distance between mouth and mike. The engineer can only balance volume levels, but the chance of getting a blended sound is greater if the mike distances are comparable.
Singing with a Sound Track
Here again, the engineer will be able to get a good balance between the voice and track if there is no distortion, in addition to no popping. This is especially important if the sound track includes one or more voice tracks as well as the accompaniment track.
Presence
When the mike is held too close, it can change the illusion the audience has of the relative presence of the singer and the track; the singer will seem very close with the accompaniment far away.
Making a Sound Check
You'll seldom get the luxury of making a sound check in a full house. However, you should use performance volume and presence during your pre-service sound check even though the church is practically empty. Don't use a tiny, timid voice during your sound check if you plan to use a big, dramatic voice during the performance. Engineers don't like those kinds of surprises; your audience won't, either.
Handle Your Mike with Kid Gloves
Some mikes are well insulated against external sound. Keep an ear tuned to extraneous sound that you may be caused by the way you handle your mike and act accordingly. If your mike has an on/off switch, slide it, don't snap it. Your engineer should have your level down while you're doing noisy things like taking the mike out of the clip at the top of a stand. However, if you know the mike is hot (on), slightly twist it counterclockwise while you take it off the stand.
Is This Mike On?
Never blow into a mike to see if it's on. In addition to making an unpleasant sound, the moisture from your breath isn't good for the mike. Without an audience, speak into the mike using the same distance and volume you'll be using for an audience. Include a couple plosives for this check, like the Peter Piper nursery rhyme. If an audience is present, tap the tip of the mike gently or rub it with your fingertips.
Feedback!
That unpleasant howling and whistling sound is called "feedback." It happens when sound travels from the speakers back into the mike from too short a distance. Feedback is most likely to occur in a relatively small room while using a portable sound system at a high volume level. To control feedback in such a situation, move a little farther from the mike and stop speaking until the feedback subsides If the feedback is violent and you're sure it's your mike, turn off your mike switch until your level is reduced at the amp. You may also try to shield your mike from the speakers with your body. If the mike is handheld, point it at a point in the room where there are no speakers. A room with a low ceiling and speakers in the ceiling is very prone to feedback
