The “Second Life” of Plastics?: On Toxic Recycling

By Xavier Sun, Taiwan Zero Waste Alliance

We know most plastics can be recycled, turned into recycled plastic pellets in recycling facilities, and sold to other plastic manufacturing factories (domestic or abroad) to be processed into new plastic products.  However, we have very little knowledge about the (hazardous) chemicals that are also “recycled” during this process.

It is actually a “toxins in, toxins out” situation. Take PVC for example. The first products made of “virgin” PVC may contain many other “functional chemicals”, such as phthalates and fire retardants. While the lifecycle of these virgin PVC products ends in recycling facilities (although better than incinerators), the functional additives stay in the newly processed and recycled PVC pellets.

Since 2018, many countries have found hazardous substances in imported toys. The International Pollutants Elimination Network (IPEN) reveals in their report,  “Toxic Loophole” that worldwide, toys made from recycled plastic, contain toxic substances such as dioxins and brominated flame retardants. 

Meanwhile, the report, “Worldwide Contamination of Recycled Plastic Globally”, analyzed recycled High-Density Polyethylene (HDPE) pellets from different countries and all were found to contain a broad spectrum of hazardous chemicals including UV-blockers, brominated flame retardants, and bisphenol-A (BPA) (See Figure 1). The three chemicals found by the study have been conclusively proven to have endocrine-disrupting properties and can cause harm to human health. 

Figure 1. The “high concern” and ”hazardous” chemicals found in recycled HDPE plastic pellets.

The report also discloses the lack of regulation or data transparency of the chemicals present in both virgin and recycled plastic pellets. In manufacturing plastic, UV-blocks and flame retardants could be added in most upstream plastic pellets due to the flammability of most plastic products and their vulnerability to sunlight. In the recycling process, these chemicals are retained and will still be present in the recycled pellets. The BPA detected in almost all samples tested might indicate mis-sorting of recycled polycarbonate with HDPE. Hence the inclusion of hazardous and high-concern chemicals may re-enter the whole life cycle of plastics again and create a “Toxic Circular Economy”.  

With the lack of transparency and government regulations, the ingredient list of recycled pellets is not certain, and there could be more hazardous chemicals that may be transferred into recycled-plastic-made products that the study was not able to identify.

With the massive overproduction of virgin plastic pellets, the trend and amount of plastic recycling must increase accordingly. However, given the concerns raised by the IPEN’s research, transparent data on chemicals in plastic pellets and the mandatory testing of plastic pellets (both virgin and recycled) using reliable but cheap testing methods should be established so that people can have a clear idea of “what kind of products made by these pellets are acceptable”.


  1. Straková, J., DiGangi, J., Jensen, G., et al (2018 October) Toxic Loophole: Recycling Hazardous Waste into New Products. International Pollutants Elimination Network.
  2. Brosché, Ph.D.1 , S.,  Strakova, MSc.1,2, J., Bell, MSc.1, L.,  Karlsson, Ph.D, T., (2021 December) Widespread Chemical Contamination Recycled Plastics Globally.  International Pollutants Elimination Network,
  3. International Pollutants Elimination Network (2022 February) How Plastics Poison the Circular Economy.
  4. Center for International Environmental Law (2017 September) Fueling Plastics: Fossils, Plastics, and Petrochemical Feedstocks.