Exfoliating plastic microbeads have become the bogeymen of beauty. Consumers were alerted to the cosmetics industry’s widespread use of these tiny beads – typically made of polyethylene (PE) – as part of the wider ocean plastics issue.
While, at this juncture, PE microbeads for exfoliation have been widely and voluntarily phased out of cosmetic formulations, there remains demand for replacements that offer the benefits of plastic microbeads with none of the environmental damage.
A toxic addition
Most plastic microbeads are small enough to be considered a microplastic, with microplastics defined as polymer-based, in solid form and under 5mm in size.
“Microplastics are very small and when they’re released into the environment it makes them readily available to being ingested by organisms living in that environment,” says Peter Simpson, a Senior Scientific Officer at the European Chemicals Agency (ECHA).
“After ingestion, they can be associated with adverse effects. They can be toxic. Sometimes it’s not the polymer which makes up the plastic that’s toxic. It can be other substances – colours or materials to influence hardness or softness – within that polymer matrix causing adverse effects. There can also be impurities from manufacture that are in the polymer and these can contribute to the toxicity.
“The other issue is that they’re very resistant to degradation once they’re in the environment,” he adds. “Because they’re there for a long time they’re constantly available to cause these adverse effects.”