On January 1st, 2019, Pittsburgh area recycling bins were rocked by a tremendous scandal. As they waited patiently for curbside pick-up, they were struck by the uncanny notion that something was missing. As of January 1st, that something was glass.

Many residents in the greater Pittsburgh area have by now received notification that glass is no longer recyclable (City of Pittsburgh residents are at present still able to recycle glass). It’s been a quiet campaign, and the decision has avid recyclers scratching their heads. Glass has always been a stalwart candidate for reuse, as was drilled into our brains in every cheery biology video. The change though is far from accidental, and its timing reflects seismic shifts in the global recycling market. So why can’t you put glass in your recycling bin? We’ll break it down to 3 (nuanced) reasons, because like your pre Kondo-Marie closet, it’s all a bit cluttered.

The Industry Doesn’t Want Your Dirty Recyclables

The primary reason for your local glass rejection lies at the other end of the recycling supply chain. For decades, China has accepted the bulk of the world’s reclaimed materials. In 2017 alone, the U.S. sent $5.6 billion worth of recyclable material to the eastern shores. However, as of 2018, China has banned 24 types of previously accepted materials and, more importantly for glass, any material that is more than .5 percent ‘contaminated.’ As per the policy, dubbed The National Sword, contamination comes from left-over food, like oil and grease, or the addition of unsorted materials, like small pieces of glass.

In reality, the contamination standard doesn’t affect recycling glass itself. Because of its weight, glass is generally processed and remanufactured no more than 600 miles from its source. In fact, domestic industries have met .5 percent contamination standards since the 1990s. What it changes is the contamination of other mixed material loads, those that could theoretically be sold to China. By some estimates, 25% percent of US recycling is contaminated, meaning that 1 in 4 tons yields absolutely no value. As Western Regional Director of the Pennsylvania Resources Council Justin Stockdale explains, “By technological consideration, the same things that were recyclable before are still recyclable today. What’s changed fundamentally is who processes our materials, or in this case, who doesn’t.”

Shattering Old Markets

So instead of selling contaminated recyclables to China, waste haulers now have to clean and separate the materials themselves, or pay to send them to an intermediary facility. To be clear, broken glass is recyclable. In fact, many manufacturers prefer glass in ‘cullet’ form. But the separation process requires more labor, and more expensive machinery for extraction. According to the Northeast Recycling Council, 65% of MRFs (Material Recovery Facilities serve as the first recycling sorter) perform no additional cleaning, while 67% haven’t upgraded their equipment in the past three years.

Ultimately, the decision to include or exclude glass is based on cost. Can the recycling hauler or MRF guarantee a high enough price per ton, now or in the future, to warrant the investment? In some cities with a Zero Waste mandate, material sorters rely on high volume to maintain a profit. Balcones Resources in Austin, Texas installed cleaning and sorting machines for their estimated 1,200 tons of glass per month. The glass is then sold down market for more specific processing.

For Resource Management Cos. in Chicago, profit was about diversifying the types of products they sold. The company uses about half of their glass for bottle cullet, with 40% being ground for insulation and the remaining 10% processed into super fine grit used for carpet backing. As president Cal Tigchelaar explained to Recycling Today Magazine, “Instead of having to pay $10 to $15 a ton to another company to take [the glass] off our hands, we’re selling it for $85 to $125, less the costs we have to put into it.”

Like any commodity, prices for recycled glass vary. Though data for 2019 is not yet available, according to American Recycler, “clean single-stream glass pricing has been very stable…[with] approximately the same value as mixed paper in North America.” However, for the approximately 70% of MRFs who produce mixed color or low quality glass, prices have dropped precipitously. If we also consider that many recycling haulers own the landfills themselves, the cost to haul the unused glass has little impact on their overall profit calculations.

Why Stop Now?

Recycling markets have been in flux for the past year, so why have we only started to hear about it? The final puzzle piece lies in new recycling contracts signed by several municipalities throughout the region. As of January 1st, the contracts no longer cover glass recycling, and won’t for the next 5 years. In previous decades, municipalities actually made money by selling their recyclables, but recent years require cities to pay for their hauling through a surprisingly wide variety of contractual agreements. Depending on their size and budget, local governments can pay by number of houses, by quantity, in addition to setting specific waste reduction targets and types of material separation.

What is the alternative?

Some affected communities and waste haulers are looking into alternative ways to recycle glass and the banned forms of plastic, like special collection days or drop off points. Many experts believe that reverting to the days of consumers separating their recyclables could also help alleviate the glass issue. Pre-sorting can decrease contamination by more than 10% in some cases, and the process forces consumers to think critically about their disposal patterns.

“When you look in your curbside recycling bin, ask yourself what is the value of those materials? What can they be turned into?” Stockdale said. “That’s where recycling really begins.” For now, the bulk food aisle offers packaging free choices, while a little soap and water goes a long way in removing debris. Plus, you never know what fits in an old Prego jar.