This article will go best with a cup of fresh tea. Go ahead and make one – I’ll wait. And mind your tea leaves while you’re at it, they might one day save your life in ways you don’t even imagine.
Tea leaves, one of the compounds that make up that cup of fragrant liquid you enjoy right now, are the chief ingredient in a flame retardant being developed to help consumer products go green.
Flame retardants are essential to our daily lives in more ways than one might expect. If you’re reading this on a computer, sitting on a couch, in the comfort of your home, then you’re surrounded by flame retardant chemicals.
We use them to ensure electronic devices meet fire safety criteria, as a standard safety measure in building construction, and woven into fibers and soft furnishings to provide an extra guard against burns.
With so much protection all around us, it’s no wonder the spread of fires has decreased dramatically since the 1980s.
However, traditional flame retardants, like the ones in the couch you might be sitting on, are synthetic polymers containing high concentrations of semi-volatile organic compounds.
We have known for a while that they tend to accumulate in the body, and possibly to cause health problems.
It’s true that the U.S. Environmental Protection Agency imposes requirements that manufacturers must meet to make sure customers remain safe, but flame retardants do spark fiery debates, pun intended.
And like many synthetics, these chemicals don’t just pose a risk for people exposed to them regularly: when thrown away, they contaminate the environment and tend to persist for a long time.
The Secret Properties of Tea Leaves
Despite their importance, the excellent work done by flame retardants doesn’t quite justify the questionable concoction of the compounds that compose them.
That’s where Bob Howell, an organic chemist at Central Michigan University, comes in. His team of researchers is creating a new generation of flame retardants made from plants. Tea leaves, to be exact.
The raw ingredients for this new, green retardant are gallic acid and a substance called 3,5-dihydroxybenzoic acid. Gallic acid is a little bundle of carbon, hydrogen, and oxygen – that compound that makes up your cup of tea.
How Do Eco-Friendly Flame Retardants Work?
3,5-dihydroxybenzoic acid comes most often from buckwheat. When treated with a chemical called phosphoryl chloride, these unpretentious compounds easily convert into flame retardant phosphorus esters.
To test the newly developed flame retardant, Howell and his team burned bits of resin used to make electronics.
The retardant-laced chips took longer to ignite, and burned for less than ten seconds. The untreated chips, on the other hand, burned until the flames have eaten them away altogether.
Another test measured the minimum amount of oxygen required to keep the resin chips burning. Higher minimum oxygen levels mean a better flame retardant, and it corresponds to a reasonably straightforward application: if we smother the flame, will it keep burning?
Howell’s retardant-treated resin chips wouldn’t burn without at least a 33% oxygen environment, while the untreated chips caught fire in almost half that amount: just 19% oxygen.
Howell’s research team hasn’t yet tested the toxicity of the new fire retardant. However, other studies on similar compounds suggest the new retardant might be less harmful than those currently in use.
It isn’t a surprise: plant-derived substances are generally less volatile than synthetic options. They’re also biodegradable, so won’t contaminate the environment.
And organisms are accustomed to consuming these compounds; remember your cup of tea?
Treat your tea leaves with more respect next time, will you? One day they may save your life in more ways than one!
- Science News. Plant-based fire retardants may offer a less toxic way to tame flames. [https://www.sciencenews.org/article/plant-based-fire-retardants-may-offer-less-toxic-way-tame-flames]
- ChemicalSafetyFacts.org. Flame Retardants. [https://www.chemicalsafetyfacts.org/flame-retardants/#targetText=Flame%20retardants%20refer%20to%20a,not%20a%20family%20of%20chemicals.]
- Earth.com. Scientists are creating safer flame retardants using plants. [https://www.earth.com/news/safer-flame-retardants-plants/]
Photo source: Science News
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