UNTIL I STARTED working on this week’s story about global challenges that rocked recycling in Washington and beyond, I had no idea what a dirty business it was.

People throw all manner of things into their recycling bins: soiled diapers, old blue jeans, hose caddies, leather belts, tubs of spoiled hummus, wadded-up plastic wrap streaked with spaghetti sauce.  As photographer Ellen M. Banner and I tracked the contents of Seattle’s blue bins from the facilities where the waste is sorted to the plants where it’s turned into cardboard, wine bottles or rebar, we saw at every step the headaches all that garbage causes.

The cover story: With recycling’s dirty truths exposed, Washington works toward a cleaner, more sustainable system

At a massive “materials recovery facility” in Seattle’s Sodo neighborhood, I poked through a mountain of glass shards ready to be trucked down the road to be recycled into wine bottles. But the pile was laced with shreds of paper, plastic, metal — even a CO2 canister and the earpiece from a pair of glasses. All that garbage has to be removed, or it gums up the recycling process.

Part of the problem is us, when we’re too lazy to rinse out jars and cans or take the time to study the “what’s acceptable” charts before we toss in items of questionable recyclability. But the system is to blame, too.

Why are those charts so convoluted to begin with? Why is so much of the packaging that encases everything we buy impossible to recycle? Utilities generally charge people for garbage collection — not recycling, even though it’s not free. So people sign up for the smallest, cheapest bin possible, and when that gets full, they start chucking trash in with the recyclables. Single-stream collection, where everything goes into the same bin, is easier for residents and cheaper for the haulers and their one-person trucks. But the more things are mixed, the bigger the mess.

I’ve changed my behavior. I’ve taken the “empty, clean and dry” mantra to heart, and I don’t put anything dubious in my blue bin. But in order to really fix recycling — to make it sustainable and truly green — legislators, local leaders and utility managers need to step up to fix some of the system’s inherent flaws.

And there’s no use ignoring the ultimate answer, either: All of us need to stop buying, using and throwing away so much stuff in the first place.