Armed with arm candy: Bracelets can detect people's chemical exposures
Silicone in wristbands absorbs chemicals. Researchers used modified ones to test people's exposure to 1,200 substances, such as flame retardants and cigarette smoke.
Wristbands are the accessory of choice for people promoting a cause. And the next wave of wrist wear might act as a fashionable archive of your chemical exposure.
Researchers at Oregon State University outfitted volunteers with slightly modified silicone bracelets and then tested them for 1,200 substances. They detected several dozen compounds – everything from caffeine and cigarette smoke to flame retardants and pesticides.
"We were surprised at the breadth of chemicals," said Kim Anderson, a professor and chemist who was senior author of the study published in Environmental Science & Technology.
Addressing the weak link
Beginning with Lance Armstrong's Livestrong, the cheap, colorful, rubbery wristbands have been a popular fad over the past decade in promoting charities and other affiliations.
Anderson initially tried to use silicone pendants attached to necklaces to test for contaminants. But then, at a football game she saw "all kinds of people, even burly men" sporting wristbands. That's when the idea hit her.
Silicone is porous and acts similar to human cells, so once chemicals are absorbed by the wristband, "they don't want to go back to the water or the air," Anderson said.
"This study offers some real possibilities to address the weak link in epidemiological studies – which is the exposure science," said Ted Schettler, science director at the Science and Environmental Health Network, a nonprofit environmental health advocacy organization.
Roofers wore wristbands, which quantified their exposure to chemicals in tar. (Credit: John/flickr)
The bracelets "can identify both chemicals and mixtures, and this could easily be applied to larger groups to see which compounds are showing up most commonly," he said.
Thirty volunteers wore the orange and white Oregon State wristbands for 30 days. Forty-nine compounds were found in them, including flame retardants, indoor pesticides such as pet flea medications, caffeine, nicotine and various chemicals used in cosmetics and fragrances.
In addition, eight volunteers who worked as roofers wore the wristbands for eight hours. The researchers were looking for polycyclic aromatic hydrocarbons (PAHs), which are in roofing tar. All of the roofers' wristbands had the compounds, including 12 on a federal priority list of harmful pollutants. As expected, roofers who wore less protection and worked in more enclosed spaces had higher levels of the chemicals on their wristbands, Anderson said.
Before outfitting the volunteers, the researchers had to remove chemicals that are introduced into silicone during manufacture.
Anderson said the bracelets are a big step up from stationary air monitors, which only capture a snapshot in time and may not be near people. Measuring individuals' exposures usually means monitors worn in backpacks, which are difficult to use and expensive.
The bracelets are first screened to see which chemicals are there, and then the researchers can measure concentrations of specific ones. The wristbands won't detect some particulate matter, and it's unclear if they will pick up some of the more volatile pesticides.
Volunteers wore these Oregon State silicone bracelets for the study. (Credit: Oregon State University)
Emily Marquez, a staff scientist with the advocacy group Pesticide Action Network, said the potential to use a wristband to quantify exposure to tens of thousands of compounds is exciting.
Schettler said the wristbands could help agencies, such as the Centers for Disease Control and Prevention, narrow their focus when they test people for contaminants.
"We could start asking questions like 'why did person A have that chemical in their wristband, but person B didn't'?" he said.
Anderson and colleagues have several other wristband projects, including agricultural fields in Africa and Peru, and hydraulic fracturing sites in the United States.
But don't plan on running out and buying a personal chemical-monitoring bracelet just yet. As of now, they still have to undergo a laboratory analysis to see which chemicals show up.
Just like any new wristband, the fad caught on for the researchers, too. "There was definitely some caffeine on mine," Anderson said.
Banner credit: Alexa Clark/flickr