The householder's part of recycling feels complete at the kerb: rinsed, sorted, lids on or off according to the leaflet. What happens next is a supply chain, and like any supply chain it has rejects, price crashes and quality control. Understanding it explains the uncomfortable statistic that a meaningful share of collected recycling is burned, buried or shipped rather than remade.
The first filter is contamination. Recycling is sold as a commodity, and buyers specify purity. Food residue soaking into cardboard, a greasy pizza box, glass smashed into paper, or the perennial villain, the plastic bag tangling the sorting machinery, can downgrade a whole lorryload from sellable material to waste. Wishcycling, tossing in the hopeful maybe-recyclable, makes this worse: the broken toy or laminated pouch does not get recycled by optimism, but it can spoil the batch that would have been.
The second filter is the material itself. The bin treats all recyclables as one virtuous category. Chemistry does not. Aluminium and steel recycle essentially forever at a fraction of the energy of virgin production, and glass similarly, which is why those streams reliably work. Paper fibres shorten with each cycle but manage several rounds. Plastics are the hard case: dozens of polymer types, only a couple with strong end markets, most degrading with each pass, and many everyday formats, films, black trays, multi-layer pouches, having no economic recycling route at all. When export markets for low-grade plastic tightened after China's import ban, material with no buyer accumulated precisely because it had nowhere honest to go.
Where the fixes actually are
The instinctive response is to ask households to try harder, and clearer local rules do help, since confusion drives contamination. But the real control sits upstream. Packaging designed for recycling, single polymers, no carbon-black trays, separable labels, determines whether the material has a market before anyone buys the product. Extended producer responsibility rules, now arriving in the UK, charge manufacturers for the end-of-life cost of their packaging, which for the first time makes the unrecyclable pouch a line on its maker's invoice. Deposit return schemes lift the quality of collected bottles and cans by keeping them clean and separate.
For the household, the honest guidance is shorter than the anxiety suggests. Follow the local list rather than intuition, keep food and bags out, and favour packaging that visibly belongs to the streams that work, metal, glass, paper and clearly labelled bottles. The rest of the problem belongs to design and policy, and pretending otherwise has mostly produced guilt where a producer's invoice would have produced change.
