Black-coloured plastic used in children’s toys, takeout containers, kitchen utensils and grocery meat and produce trays may contain alarming
Black-coloured plastic used in children’s toys, takeout containers, kitchen utensils and grocery meat and produce trays may contain alarming levels of toxic flame retardants that may be leaching from electronic products during recycling, a new study found.
“A product with one of the highest levels of flame retardants were black plastic pirate coin beads that kids wear — they resemble Mardi Gras beads but more for costume wear,” said lead study author Megan Liu, science and policy manager for Toxic-Free Future, an environmental advocacy group.
“That particular product had up to 22,800 parts per million of total flame retardants — that’s almost three per cent by weight,” Liu said. “Kids will often play with toys multiple days in a row until they tire of them.”
Multifunctional flame-retardant foam with strong antibacterial properties developed
A new study combining fire safety, hygiene, and sustainability has led to the development of a multifunctional polyurethane foam that resists flames and suppresses smoke, while also preventing bacterial growth.
The new material, which also exhibits improved mechanical properties, could be particularly valuable in hospitals and public transport, among other applications, where fire resistance and antibacterial protection are both critical for safety and health.
The research, carried out by Dr. Yingming Li from Chongqing Jiaotong University, and Prof. Dr. De-Yi Wang from IMDEA Materials Institute and the Universidad Francisco de Vitoria in Madrid, introduces a biomass-derived organic aerogel that dramatically enhances the performance of the widely used flexible polyurethane foam (FPUF).
Two garments subjected to a fire test. The one in the left three frames is fire resistant. The one on the right isn’t. Demonstration tests with garments. 1910.
Flame retardants created from plant materials could be less harmful to the environment than traditional flame-smothering chemicals.
Flame retardants are going green.
Using compounds from plants, researchers are concocting a new generation of flame retardants, which one day could replace the fire-quenching chemicals added by manufacturers to furniture, electronics and other consumer products.
Many traditional synthetic flame retardants have come under fire for being linked to health problems like thyroid disruption and cancer (SN: 3/16/19, p. 14). And flame retardants that leach out of trash in landfills can persist in the environment for a long time (SN: 4/24/10, p. 12).
The scientists have not yet performed toxicity tests on the new plant-based creations. But “in general, things derived from plants are much less toxic … they’re usually degradable,” says Bob Howell, an organic chemist and polymer scientist at Central Michigan University in Mount Pleasant.
Howell’s team presented the work August 26 in San Diego at the American Chemical Society’s national meeting.
The raw ingredients for these plant-based flame retardants were gallic acid — found in nuts and tea leaves — and a substance in buckwheat called 3,5-Dihydroxybenzoic acid. Treating these compounds with a chemical called phosphoryl chloride converted them into flame-retardant chemicals named phosphorus esters. Since these plant-based ingredients are common, and the chemical treatment process is straightforward, it should be relatively easy to manufacture these flame retardants on a large scale, Howell says.
A resin commonly used in electronics and vehicles typically catches fire easily (left), but a plant-based flame retardant can keep the resin from going up in flames (right).
CREDIT: YOSEPH GETACHEW
Howell and colleagues tested the flame retardants in a resin used to make electronics, cars and planes. Compared with chips of pure resin, the resin laced with flame retardant took longer to go up in flames. And “it doesn’t burn for very long, once you get it going,” Howell says. Treated chips were snuffed out in less than 10 seconds, whereas untreated chips blazed until no resin remained. The experiments did not compare the plant-based flame retardants with traditional fire-resistant substances.
The researchers also measured the minimum amount of ambient oxygen required to keep the resin burning. “The higher that number, the better the flame retardant,” Howell says. In gas-filled chambers, untreated resin burned amidst just 19 percent oxygen, whereas treated resin wouldn’t burn without at least 33 percent oxygen.
