"Biodegradable" has become a common label on plastic packaging in Kasarani shops over the past few years, often presented as a straightforward environmental reassurance. In practice, the term is more complicated and more commonly misapplied than most shoppers realise, and it's worth explaining clearly, since it directly affects how we ask households to segregate this material.

What "biodegradable" technically means

In the strictest sense, biodegradable material breaks down through natural biological processes — bacteria, fungi and other organisms consuming and decomposing it — into basic natural compounds, typically over a defined and reasonably short timeframe. Genuinely biodegradable materials, like unlaminated paper or actual food waste, meet this definition clearly and predictably.

Why plastic labelled "biodegradable" often doesn't behave this way

Much plastic marketed as biodegradable requires very specific conditions to actually break down as claimed — industrial composting facilities with controlled temperature, moisture and microbial activity that simply don't exist in a typical household compost pile, let alone in general landfill or open dumping conditions. Left in an ordinary environment, so-called biodegradable plastic can persist for years, behaving essentially like conventional plastic despite the label, because the specific breakdown conditions it was designed for were never actually present.

The difference between biodegradable, compostable and oxo-degradable

These terms are often used loosely and interchangeably in marketing, but they mean genuinely different things. Compostable materials are designed to break down specifically under composting conditions, ideally including the kind of home composting we cover in our composting guide, though industrial composting requirements sometimes still apply. Oxo-degradable plastic is conventional plastic with additives that cause it to fragment into smaller pieces over time under sunlight and oxygen exposure — it doesn't fully biodegrade so much as break into microplastics, which many environmental researchers consider a worse outcome than remaining intact, since microplastics are harder to recover and more easily enter water systems and food chains.

Why this matters for our segregation guidance

Because "biodegradable" labelling on plastic is inconsistent and often unreliable in ordinary conditions, we advise households to treat labelled plastic packaging the same as conventional plastic for segregation purposes — sorted into the recyclable stream if it's a type we can process, like PET or HDPE, or general waste if it's a mixed or unclear material, rather than assuming a biodegradable label means it can simply be discarded without consequence or added to a compost pile.

What genuinely compostable packaging looks like

A smaller but growing category of packaging is genuinely designed for home composting — certain plant-fibre-based wrapping, some paper-based alternatives to plastic film. These typically look and feel noticeably different from plastic, often visibly fibrous or paper-like rather than smooth and glossy, and are a genuinely useful addition to a compost pile if you have one, unlike most plastic regardless of its labelling claims.

How to think about a "biodegradable" label practically

  • Don't assume a biodegradable label means an item can go into your organic compost stream; check whether it's genuinely plant-fibre or paper-based rather than plastic with an additive.
  • Treat labelled plastic packaging the same as conventional plastic for segregation, sorting it as recyclable or general waste based on the underlying material type.
  • Be skeptical of "oxo-degradable" or "oxo-biodegradable" labels specifically, since these describe fragmentation into microplastics rather than genuine breakdown.
  • When genuinely unsure, ask our team at a buy-back point or during a collection round; our collectors are trained to recognise the more common packaging types in circulation locally.

Why this matters for the wider push toward reduced plastic use

Loosely regulated environmental labelling risks giving shoppers false confidence that a purchase is more responsible than it actually is, potentially reducing the pressure toward genuinely reducing plastic use altogether, a theme we've covered in our piece on cutting waste before collection even happens. Understanding what these labels do and don't guarantee is part of making informed choices rather than relying on packaging claims alone.

How we handle this during our schools and household education sessions

We've added a short, specific segment to our recycling education sessions addressing biodegradable labelling directly, since it's become common enough in local packaging that residents and pupils regularly ask about it. Keeping this guidance current is an ongoing task, since packaging and labelling practices continue to shift as more products enter the market with varying, sometimes exaggerated environmental claims.

Frequently asked questions

Can I put "biodegradable" plastic packaging in my home compost pile?

Generally no, unless it's specifically labelled as home-compostable and appears genuinely plant-fibre or paper-based rather than plastic-like; most biodegradable plastic requires industrial composting conditions not present in a household setup.

What is the difference between biodegradable and oxo-degradable plastic?

Biodegradable plastic is intended to break down into natural compounds under the right conditions; oxo-degradable plastic simply fragments into smaller plastic pieces, or microplastics, which many researchers consider more environmentally harmful, not less.

How should I segregate plastic packaging labelled as biodegradable?

Sort it the same as conventional plastic — recyclable if it's a type we accept, like PET or HDPE, or general waste otherwise — rather than assuming the label changes how it should be handled.

For more on household segregation generally, see our guide on why waste segregation at source matters.