One wrong item in a recycling bin can be enough to send the whole load to landfill instead of being recycled. That’s recycling contamination.
Contamination usually comes down to one of two things: the wrong item in completely, or the right item in too dirty to process. Both spoil the wider recycling stream.
Here’s what counts as contamination, what it costs, and how to keep your bin out of the reject pile.
What counts as recycling contamination – Advice from Glasgow’s garden clearance team
A contaminant is anything you put out to recycle that shouldn’t be there.
It counts either because it can’t be recycled at all, or because it’s dirty enough to spoil the recyclable materials around it.
Both count as contamination, even though only one is technically non-recyclable.
Putting the wrong things in is the obvious version: a nappy, a garden hose, largely unrecyclable polystyrene packaging, a broken toy.
The less obvious version is putting the right things in the wrong state, like a jar still half full of sauce.
A clean glass jar and that same jar coated in sauce are recycled completely differently.
One goes straight for reprocessing. The other risks spoiling other items packed around it in the lorry.
Common items that contaminate a bin
A greasy pizza box, a takeaway food container, or a yoghurt tub with sauce on the sides doesn’t look like a problem on its own.
Once it’s packed against paper and cardboard in the lorry, the grease transfers and ruins whatever it touches.
Plastic bags, bubble wrap and film lids cause a different kind of damage. They jam sorting machinery built for rigid plastic, and a jammed machine stops the whole load moving until someone clears it by hand.
Liquid causes damage too.
Left in a bottle, it soaks into paper and cardboard nearby and ruins them. An old t-shirt tangles in machinery built for cardboard and plastic and does similar damage.
One of the most serious risks is a lithium battery. A vape can spark inside a bin lorry and start a fire.
Broken glass causes its own cuts and hazards for anyone sorting the load by hand.
What happens to a contaminated load
Recycling gets sorted at a materials recovery facility (MRF for short), one of several recycling facilities across Scotland.
Machines and workers there separate different materials so each one goes for proper reprocessing. Contamination breaks that recycling process.
Soft plastic can clog the machinery outright. Food waste and liquid soak into paper and cardboard, making previously clean materials unusable.
Once that happens, an entire load that would otherwise have been easily separated stops being worth sorting.
Workers can pull out an obvious offender by hand, but that only works item by item.
Once contamination has already spread through a load, there’s no practical way to separate it back out.
When sorting no longer makes financial sense, the MRF sends that load to landfill instead.
One wrong item rarely does this alone, but it doesn’t take much added contamination before a full lorry gets diverted.
Why contamination matters
Every rejected load pushes down recycling rates and adds cost. It still has to go to landfill or incineration, after already being collected and transported once.
Contamination also reduces the value of what does get recycled.
Recyclers pay less for contaminated material than for a clean batch of plastic or paper, so the whole recycling economy runs less efficiently.
Landfill has its own separate problem.
Food and other organic material trapped in landfill decomposes without oxygen and produces methane.
Methane is a far more powerful greenhouse gas than carbon dioxide in the short term.
How to avoid contaminating your recycling
Give containers a quick rinse before they go in the bin. You don’t need spotless items, just empty and mostly clean, since a light film is fine but sauce or crumbs are not.
Food scraps and leftovers belong in a food waste bin or a home compost heap, never mixed in with packaging.
Keep soft plastic, textiles and anything electronic out of your household recycling bin entirely.
Soft plastic often needs a separate collection point, textiles belong in a clothing bank, and batteries or vapes need dedicated recycling.
When you’re not sure
Check your kerbside collection guide before assuming you can recycle something.
What one local council collects at the kerb, another might not, so a quick check saves a whole load being rejected over one wrong item.
When in doubt, leave it out, since one uncertain item can get a whole bin rejected. That costs more, in time and in recycling lost, than binning that single item as general waste instead.
Recycle what you’re sure of, and dispose of the rest as general waste.
Recycling contamination questions answered
What happens if I put the wrong things in my bin?
At best, sorting staff remove the item and the rest gets recycled normally. At worst, especially with soft plastic or liquid, contamination spreads and the whole load goes to landfill instead.
What’s the biggest problem with recycling right now?
Contamination is consistently one of the biggest issues, since it drives up costs and lowers the amount that actually gets reprocessed. Rinsing containers and keeping soft plastic and pizza boxes out of the bin fixes a lot of it.
Can old clothes go in a clothing bank?
Yes, clean and dry clothes are exactly what clothing banks want, including ones that are worn out or have a broken zip. Wet, mouldy or heavily soiled textiles are the ones to avoid.
What does it mean if my bin gets tagged?
A tag or sticker on the lid means the crew spotted contamination and left the bin unemptied. It usually explains which items caused the problem, so removing those and presenting the bin again next collection normally sorts it.
How the Junk-It team sort what we collect
House clearances turn up exactly this kind of mixed load: old electricals, textiles, half-empty tins, and furniture.
All of it needs sorting properly rather than dumping in one bin or a skip.
Our eco-friendly junk removal team sorts it properly instead.
We’re SEPA registered (Scottish Environment Protection Agency) and sort everything ourselves.
Over 85% of what we collect stays away from landfill through proper reuse, recycling and donation. Anything still in good condition goes to donation first.
We even have blogs on how to upcycle your items to avoid calling us in the first place!
If you’d rather not sort a big clear-out item by item, get in touch for a free, no-obligation quote. We’ll handle it properly from the start.
Call us on 0141 433 4330 and get your hassle-free item removal sorted!
