Different methods for collecting recyclable materials result in different degrees of quality in the collected materials. Research for the 2009 report on single-stream recycling showed that only 40% of glass from single-stream collection is recycled into containers and fiberglass. Forty percent of glass winds up in landfills, while 20% is small broken glass ("glass fines") used for low-end applications. In contrast, mixed glass from dual-stream systems yields an average of 90% being recycled into containers and fiberglass, with 10% glass fines used for low-end applications, and nearly nothing sent to landfill. In container-deposit systems, color-sorted material results in 98% being recycled and only 2% marketed as glass fines.

The recovery rate for glass containers has shown minimal growth between 1994 and 1997, increasing from 29 percent in 1994 to just 31 percent in 1997. But, because glass container production has declined, the number of tons of cullet (crushed glass) recycled actually dropped from 3.14 million tons in 1994 to 2.92 million tons in 1997.

Of greater concern is the fact that fewer tons of color-sorted glass was available to make new glass bottles and jars. This is due in part to the trend towards commingled curbside collection of recyclables. When materials are collected 'commingled' (not separated) they become contaminated, thus lowering the value of the materials.

The impact of contamination can be seen in the numbers from 1997, showing that cullet purchases for making new glass containers was the lowest it had  been in the preceding six years.

According to the European Glass Federation, glass recycling in Europe hit record levels in 1996. When measured against the high glass container recycling rates in sixteen European countries, the U.S. was in fifteenth place. The bar graph below compares the U.S. rate to nine of the sixteen countries surveyed.

Five countries had rates that were more than twice as high as the U.S. and two had rates that were almost twice as high. Only Turkey and the United Kingdom had rates lower than the` U.S. rate of 33 percent (not shown on the graph). Switzerland had the highest rate at 89 percent.

Countries with glass recycling rates above 70 percent have some form of 'producer responsibility' regulation in place.