Chemicals in plastics

A less-known side of plastic pollution

Jun 5, 2023 | ANNA ETTLIN
Plastics contain thousands of chemicals that can harm the environment and human health. Yet we know too little about approximately half of them. A new technical report from the United Nations Environment Programme (UNEP), co-authored by Empa researchers, reveals the extent of the problem.
Some of the areas of concern for chemicals in plastics include toys, furniture, textiles and food packaging. Image: Adobe Stock

Today's World Environment Day is dedicated to the fight against plastic pollution. Many people are aware of the environmental impact of plastic pollution and the danger of microplastics. However, there is much less awareness of the chemical pollution caused by plastics. Individual problematic substances, such as bisphenol A (BPA), have attracted media attention – but they are just the tip of the iceberg.

A recently published technical report by the United Nations Environment Programme (UNEP) provides an overview of the chemicals in plastics and identifies particularly urgent areas for action. Empa researchers Zhanyun Wang and Narain Ashta co-authored the report. "We were able to show that over 13,000 different chemicals are used in plastics," the scientists say. "A quarter of these have been shown to be problematic, and we know far too little about another 50 percent or so."

Fields of action identified

The substances are extremely varied. Many of them are used in the manufacturing of plastics, for example as precursors or solvents. There are also numerous additives, such as plasticizers, flame retardants or pigments. In the report, the authors identify ten groups of chemicals that are of high concern because they are demonstrably toxic or can very easily be released from plastics into the environment. These include, for example, certain UV stabilizers and flame retardants, biocides, and per- and polyfluoroalkyl substances (PFASs).

The report also prioritizes ten areas where chemicals of concern are particularly likely to endanger people and the environment. This is the case, for example, with plastic products for agriculture and fishing, as well as toys, food packaging, electronic devices, furniture, textiles, vehicles, building materials and many more. The researchers propose a number of measures to reduce chemical pollution, especially in these products.

"Chemicals in plastic are a hidden danger that can impact public health and the environment at the global scale," Wang and Ashta explain. "Their use should be regulated under international treaties."