Global Health Asia-Pacific May 2020 | Page 48

Holistic Health Is silicone safe for consumers? The controversial polymer might be versatile, but it hasn’t successfully stated its case on safety I t’s a food safety classification that sits on the fence. Dubbed GRAS, or “Generally Regarded as Safe”, it hardly instills confidence when it comes to items the public eats. Defined by the US Food and Drug Administration (FDA), GRAS describes a wide range of consumer products and ingredients that are put on the market with almost no oversight. First implemented in 1997, it’s a loophole that spares common items from regulatory approval. Now it’s been formalised in America’s food safety code. Many GRAS products are controversial, but among them the use of silicone in food packaging material stands out. Silicones are highly versatile groups of polymers used in food contact materials such as fluids, rubbers, or resins. They’re generally water- and oil-repellent, gas-permeable, and insoluble in water, mineral oils, and alcohol. In liquid form, they’re even added directly to food during production and processing and can be used as anti-foaming agents during sugar production, beverage processing, and washing vegetables. Silicone bakeware is incredibly adaptive and functional. Non-stick baking dishes can easily be transferred from the oven to the fridge and freezer and are microwave and dishwasher safe. Elsewhere, silicones are found in food wrapping films that allow the controlled release of active substances, such as antibacterials to improve the shelf- life of food. They’re often in everything from spatulas to the nipples on baby bottles. Their widespread use, however, has stirred some debate. Though silicones have some undoubted benefits over other polymers, scientists have been gathering evidence of chemical migration of silicone- based materials into food. Also, very little is known about the effects of long- term exposure to low doses of silicones, as designing such studies is notoriously difficult. In response, food safety authorities in Australia and New Zealand set out in 2016 to find compelling evidence of silicone’s safety in food packaging, among other things. The countries’ shared food regulator, Fsanz, then published reports that at first sight appeared to be good news for the consumer. In reality, though, these reports continued to raise questions. The papers highlighted the “lack of concrete evidence about the safety of the materials, and the fact we don’t even know very well how to measure if they are present,” said Dr Simon Brown, Professor of 46 MAY 2020 Physics at the University of Canterbury, in an analysis of the paper. “Given the very significant scientific uncertainties, I think these reports sound an appropriate note of caution: the situation is not nearly as simple as Fsanz’s key finding suggests,” he said. Yet there is still much support for silicone’s safety. “The human diet naturally contains material in the nano-metre size range, and nanoparticulate material, such as silicon dioxide and titanium dioxide, has been a component of some foods, cosmetics, and pharmaceuticals for many decades,” Dr Andrew Bartholomaeus, a consultant toxicologist and adjunct professor in Australia, told Global Health Asia-Pacific. Regardless of the particle size of soluble food components, once dissolved they’re indistinguishable from traditional materials. “Overall, the safety or otherwise of food additives and packaging components generally has very little to do with particle size,” he added, noting that, to date, no toxicological effects from silicone residue had been identified. Silicones are highly versatile groups of polymers used in food contact materials such as fluids, rubbers, or resins. GlobalHealthAndTravel.com