If the gas stove discourse has exposed you to the wonderful world of daily exposure to environmental pollution, may I suggest another culprit guaranteed to mess up your underpants? Flame retardants are chemicals used to treat every kind of household item, from mattresses to electronics to building insulation to the clothes on your back. They slow the spread of fire, but come at a price: In recent years, scientists have linked these chemicals (of which there are hundreds) to immune system disruption; reproductive damage; cancer; fetal developmental problems; and neurological dysfunction.
And that’s all before a fire actually starts. Firefighting foam used to extinguish fires may contain perfluoroalkyl and polyfluoroalkyl (PFAS), so-called forever chemicals that can be toxic to humans.
In a surprising development in materials science, researchers at the United States Department of Agriculture have developed a type of cotton that self-extinguishes when set on fire. And they did it by crossing existing cotton lines, meaning farmers can grow this cotton without a lengthy approval process. A study describing this new cotton line was published Jan. 18 in the journal PLOS ONE.
“This is the unexpected icing on the cake of a long, fruitful, and ongoing USDA project involving many scientists, years, and locations,” Gregory Thyssen, a cotton chemistry researcher with the USDA Agricultural Research Service, told an email. email to The Daily Beast. Although researchers have previously identified natural flame-retardant properties in brown cotton, “the new study is the first report of a white cotton line having the property,” he said.
Thyssen and his colleagues co-bred 11 cotton cultivars that have proven to be better than other lines at retarding fire. The cultivars were bred together in various combinations and then self-pollinated to produce hundreds of new lines of cotton.
From there, researchers grew 257 lines and analyzed the flame-retardant properties of the fibers, choosing the 30 best and worst lines to grow the following year, and the five best and worst of those to grow the year after.
The results of the selective breeding speak for themselves. According to the study, textiles woven from four of the five most flame-retardant lines self-extinguished when set on fire at a 45-degree angle. One of the most flame-retardant lines, and all of the least flame-retardant lines, “were quickly and completely consumed by flame.”
In addition, genetic sequencing of these new lines revealed that their superpower did not appear to stem from a random mutation or single gene, but rather from a complex interaction that exacerbated the flame-retardant effects of multiple genetic regions. Because the researchers have yet to work out the details of this interaction, artificial selection ultimately proved to be a more successful approach than adding or removing genes via genetic engineering. “Genetic manipulation of this trait is just not an option at this point,” Thyssen said.
In addition, in the US, multiple federal agencies play a role in the evaluation of genetically modified organisms, and GMOs have met with public opposition despite evidence that they are safe for consumers. Being naturally created through selective breeding, the self-extinguishing cotton completely avoids these problems.
“Genetic manipulation of this trait is simply not an option at this point.”
— Gregory Thyssen, USDA
Thyssen said the team plans to grow even larger fields of the new cotton varieties in the upcoming growing season, from May to September. Once they are able to increase the amount of seeds, the researchers will release them to growers for their own breeding programs. The cotton harvested during the season is also used to make yarn and various textiles, which the researchers then test for quality and flammability.
One question on everyone’s mind, Thyssen said, is the durability of cotton’s flame-retardant property: Will textiles made from it self-extinguish after many washes, or will it eventually need to be treated with chemicals? There are no answers yet. What is clear is the myriad benefits of phasing out toxic flame retardants from everyday life.