Contamination in Paper Recycling

Chemical pail containing unidentified liquid in a finished bail.

Contamination in paper recycling is a serious issue, with negative effects ranging from the strictly financial, to the health and safety of industry workers. The rapid expansion of recycling programs has seen a commensurate rise in contamination of collected recyclables. The trend towards single-stream curbside recycling (where paper and other recyclables are commingled with refuse and sorted at a processing facility) has brought contamination to the forefront of debate.

Contamination in paper recycling can refer to soiling of paper with food, grease, chemicals, or other noxious compounds, or to the inclusion of inappropriate material for the intended paper grade.

Simple soiling is easy to understand; once you’ve used a newspaper to soak up transmission fluid, for example, it is no longer recyclable. Food can also be a source of contamination, which often comes as a surprise. The truth of the matter is that it is difficult to separate pizza grease (or other food contaminants) from paper fibers. This is a major issue in the hotly contested debate surrounding single-stream recycling, as food contamination seems inevitable.

Inappropriate materials mixed in with recyclable paper are defined as one of two types, outthrows and prohibitive materials. Outthrows are materials which will need to be thrown out, literally, during the recycling process, and prohibitive materials are things which make the paper unusable. Unlike simple soiling, these are grade dependent. A material can be classified as an outthrow in one grade and as a prohibitive material in another grade. For example, brown kraft bags (grocery type) are welcome in OCC, but would be an outthrow in White Ledger. Waxed cartons or that broken stapler someone chucks into the office recycling bin are prohibitive.

If the levels of outthrows or prohibitive materials exceed those specified in the grade definition, the paper is no longer acceptable as that particular grade. It is then downgraded to an appropriate grade. In extreme cases, the paper may become worthless, and suitable only for disposal.

American Recycling’s Brian Terrel, on contamination:

“Unfortunately, sometimes we receive contaminants in the recyclable materials we receive from our customers. At best, it will result in a reduction of the redemption value of their material due to our need to physically sort out the contaminants. At worst, we may have to assess a fee to recover the landfill costs associated with contaminants or waste in the recycling loads. Because of this, we strongly emphasize the value of maintaining clean, source separated recyclables in order for our customers to receive the highest rebate possible from their materials.”

It is in everyone’s best interest to keep contamination out of the recycled paper stream. It is no exaggeration to say that the current sustainable paper industry relies on the reuse of fiber. To dispose of that fiber before it has been recycled is anathema to the industry, and results in an environmental burden on the planet, and a financial burden on everyone involved. Contamination can turn a valuable resource into trash – and that’s everybody’s problem.