Are sugarcane toothbrushes biodegradable?

How sugarcane becomes plastic

Sugarcane juice is fermented into ethanol, the ethanol is turned into ethylene, and the ethylene is polymerised into polyethylene. A 2020 review describes the result as identical to fossil-based polyethylene in its chemical, physical and mechanical properties. One producer agrees: its bio-based plastics are chemically identical to their fossil fuel counterparts. It isn’t necessarily all plant carbon: the producer says the renewable carbon content of most grades ranges from at least 84% to at least 96%.

Is it biodegradable?

No. The same review puts it simply: “Of course, bio-PE is not biodegradable.” Whether a plastic biodegrades depends on its chemical structure, not on where its raw materials came from, and even Europe’s bioplastics industry association lists bio-based polyethylene among bio-based, non-biodegradable plastics. Polyethylene itself is one of the plastics most resistant to biodegradation; complete biodegradation of it has not been achieved. UN Environment notes that the word “bioplastic” can lead people to assume a product is completely plant-based or biodegradable.

Australia’s consumer regulator has used a case very like this as a warning. The ACCC’s guide to environmental claims describes a toothbrush made from bio-based polyethylene, labelled “biodegradable approved” without testing, and counts that label as a claim likely to be false or misleading, because that plastic is not biodegradable. It’s a hypothetical example, but a pointed one.

Sugarcane plastic vs sugarcane fibre

Part of the confusion is that “sugarcane” covers two very different things. Bagasse is the fibre left over from sugarcane, used to make packaging and food service ware as an alternative to plastic. The NSW EPA lists “plant-based (e.g. made from sugarcane…)” as a marketing term that doesn’t change whether an item is plastic, while suggesting vegetable fibre, including bagasse, as an alternative. Its definition of plastic covers polymers from plant extracts or fossil fuels, lists polyethylene as plastic, and lists bagasse as not plastic.

Bin rules for compostable sugarcane items differ (as at October 2026). South Australia takes certified compostable takeaway items, including sugarcane products, in the green bin. The ACT says bagasse products go in general waste, not the FOGO bin, because they need industrial composting; items with the AS 5810 home compostable logo can go in a home compost.

The carbon claim

The case for sugarcane plastic is about carbon, not about the bin. One producer reports a footprint of -2.12 kg of CO2 equivalent per kilogram from its own life-cycle study, which runs from cradle to factory gate, so it leaves out what happens to the product afterwards. A peer-reviewed 2012 study found land-use change decisive for the climate result: in the worst case it made sugarcane polyethylene comparable to the fossil kind.

Can it be recycled?

One producer says its plastic is recyclable within existing streams for ordinary plastics. That applies to the material, not to a toothbrush: the Australian Dental Association says most toothbrushes can’t go in the home recycling bin. We cover the options in can you recycle a plastic toothbrush?

What to check on the label

• What the handle is made of. “Sugarcane” or “plant-based” doesn’t name the material. It could be polyethylene, or another plastic altogether (see PLA).
• “Biodegradable”. The ACCC says a product may only break down in certain conditions or after a very long time, and leaving that out can mislead. Ask which standard and which conditions.
• The bristles. A plant-based handle says nothing about them, and nylon is the most widely used bristle material.

Where we fit

Our handle is bamboo and our bristles are sterilised horse hair woven into the head, with no nylon and no glue. There is one small aluminium staple inside the head that doesn’t compost, so fish it out at the end. More on what breaks down and what doesn’t in our guide to compostable toothbrushes.

The short version

• Sugarcane polyethylene is chemically identical to ordinary polyethylene.
• It isn’t biodegradable, and polyethylene is among the plastics most resistant to biodegradation.
• Sugarcane fibre (bagasse) is a different material; a polyethylene handle isn’t bagasse.
• The carbon benefit is a producer’s factory-gate figure and depends on land use.